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https://dev.mysql.com/doc/refman/8.4/en/precision-math-numbers.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="precision-math-numbers">
</a>
14.24.1 Types of Numeric Values
</h3>
</div>
</div>
</div>
<a class="indexterm" name="idm46045190499376">
</a>
<a class="indexterm" name="idm46045190498288">
</a>
<a class="indexterm" name="idm46045190497200">
</a>
<a class="indexterm" name="idm46045190495712">
</a>
<p>
The scope of precision math for exact-value operations includes
the exact-value data types (integer and
<a class="link" href="fixed-point-types.html" title="13.1.3 Fixed-Point Types (Exact Value) - DECIMAL, NUMERIC">
<code class="literal">
DECIMAL
</code>
</a>
types) and exact-value
numeric literals. Approximate-value data types and numeric
literals are handled as floating-point numbers.
</p>
<p>
Exact-value numeric literals have an integer part or fractional
part, or both. They may be signed. Examples:
<code class="literal">
1
</code>
,
<code class="literal">
.2
</code>
,
<code class="literal">
3.4
</code>
,
<code class="literal">
-5
</code>
,
<code class="literal">
-6.78
</code>
,
<code class="literal">
+9.10
</code>
.
</p>
<p>
Approximate-value numeric literals are represented in scientific
notation with a mantissa and exponent. Either or both parts may be
signed. Examples:
<code class="literal">
1.2E3
</code>
,
<code class="literal">
1.2E-3
</code>
,
<code class="literal">
-1.2E3
</code>
,
<code class="literal">
-1.2E-3
</code>
.
</p>
<p>
Two numbers that look similar may be treated differently. For
example,
<code class="literal">
2.34
</code>
is an exact-value (fixed-point)
number, whereas
<code class="literal">
2.34E0
</code>
is an approximate-value
(floating-point) number.
</p>
<p>
The
<a class="link" href="fixed-point-types.html" title="13.1.3 Fixed-Point Types (Exact Value) - DECIMAL, NUMERIC">
<code class="literal">
DECIMAL
</code>
</a>
data type is a
fixed-point type and calculations are exact. In MySQL, the
<a class="link" href="fixed-point-types.html" title="13.1.3 Fixed-Point Types (Exact Value) - DECIMAL, NUMERIC">
<code class="literal">
DECIMAL
</code>
</a>
type has several synonyms:
<a class="link" href="fixed-point-types.html" title="13.1.3 Fixed-Point Types (Exact Value) - DECIMAL, NUMERIC">
<code class="literal">
NUMERIC
</code>
</a>
,
<a class="link" href="fixed-point-types.html" title="13.1.3 Fixed-Point Types (Exact Value) - DECIMAL, NUMERIC">
<code class="literal">
DEC
</code>
</a>
,
<a class="link" href="fixed-point-types.html" title="13.1.3 Fixed-Point Types (Exact Value) - DECIMAL, NUMERIC">
<code class="literal">
FIXED
</code>
</a>
. The integer types also are
exact-value types.
</p>
<p>
The
<a class="link" href="floating-point-types.html" title="13.1.4 Floating-Point Types (Approximate Value) - FLOAT, DOUBLE">
<code class="literal">
FLOAT
</code>
</a>
and
<a class="link" href="floating-point-types.html" title="13.1.4 Floating-Point Types (Approximate Value) - FLOAT, DOUBLE">
<code class="literal">
DOUBLE
</code>
</a>
data types are
floating-point types and calculations are approximate. In MySQL,
types that are synonymous with
<a class="link" href="floating-point-types.html" title="13.1.4 Floating-Point Types (Approximate Value) - FLOAT, DOUBLE">
<code class="literal">
FLOAT
</code>
</a>
or
<a class="link" href="floating-point-types.html" title="13.1.4 Floating-Point Types (Approximate Value) - FLOAT, DOUBLE">
<code class="literal">
DOUBLE
</code>
</a>
are
<a class="link" href="floating-point-types.html" title="13.1.4 Floating-Point Types (Approximate Value) - FLOAT, DOUBLE">
<code class="literal">
DOUBLE PRECISION
</code>
</a>
and
<a class="link" href="floating-point-types.html" title="13.1.4 Floating-Point Types (Approximate Value) - FLOAT, DOUBLE">
<code class="literal">
REAL
</code>
</a>
.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-ndbinfo-foreign-keys.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="mysql-cluster-ndbinfo-foreign-keys">
</a>
25.6.17.37 The ndbinfo foreign_keys Table
</h4>
</div>
</div>
</div>
<a class="indexterm" name="idm46045089201216">
</a>
<p>
The
<code class="literal">
foreign_keys
</code>
table provides information
about foreign keys on
<code class="literal">
NDB
</code>
tables. This table
has the following columns:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<code class="literal">
object_id
</code>
</p>
<p>
The foreign key's object ID
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
name
</code>
</p>
<p>
Name of the foreign key
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
parent_table
</code>
</p>
<p>
The name of the foreign key's parent table
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
parent_columns
</code>
</p>
<p>
A comma-delimited list of parent columns
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
child_table
</code>
</p>
<p>
The name of the child table
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
child_columns
</code>
</p>
<p>
A comma-separated list of child columns
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
parent_index
</code>
</p>
<p>
Name of the parent index
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
child_index
</code>
</p>
<p>
Name of the child index
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
on_update_action
</code>
</p>
<p>
The
<code class="literal">
ON UPDATE
</code>
action specified for the
foreign key; one of
<code class="literal">
No Action
</code>
,
<code class="literal">
Restrict
</code>
,
<code class="literal">
Cascade
</code>
,
<code class="literal">
Set Null
</code>
, or
<code class="literal">
Set
Default
</code>
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
on_delete_action
</code>
</p>
<p>
The
<code class="literal">
ON DELETE
</code>
action specified for the
foreign key; one of
<code class="literal">
No Action
</code>
,
<code class="literal">
Restrict
</code>
,
<code class="literal">
Cascade
</code>
,
<code class="literal">
Set Null
</code>
, or
<code class="literal">
Set
Default
</code>
</p>
</li>
</ul>
</div>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/show-replica-status.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="show-replica-status">
</a>
15.7.7.35 SHOW REPLICA STATUS Statement
</h4>
</div>
</div>
</div>
<a class="indexterm" name="idm46045169681904">
</a>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-sql"><div class="docs-select-all right" id="sa74035616"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">SHOW</span> <span class="token keyword">REPLICA</span> <span class="token keyword">STATUS</span> <span class="token punctuation">[</span><span class="token keyword">FOR</span> <span class="token keyword">CHANNEL</span> <span class="token keyword"><em class="replaceable">channel</em></span><span class="token punctuation">]</span></code></pre>
</div>
<p>
This statement provides status information on essential
parameters of the replica threads. The statement requires the
<a class="link" href="privileges-provided.html#priv_replication-client">
<code class="literal">
REPLICATION CLIENT
</code>
</a>
privilege (or
the deprecated
<a class="link" href="privileges-provided.html#priv_super">
<code class="literal">
SUPER
</code>
</a>
privilege).
</p>
<p>
<code class="literal">
SHOW REPLICA STATUS
</code>
is nonblocking. When run
concurrently with
<a class="link" href="stop-replica.html" title="15.4.2.5 STOP REPLICA Statement">
<code class="literal">
STOP
REPLICA
</code>
</a>
,
<code class="literal">
SHOW REPLICA STATUS
</code>
returns without waiting for
<a class="link" href="stop-replica.html" title="15.4.2.5 STOP REPLICA Statement">
<code class="literal">
STOP
REPLICA
</code>
</a>
to finish shutting down the replication SQL
(applier) thread or replication I/O (receiver) thread (or both).
This permits use in monitoring and other applications where
getting an immediate response from
<code class="literal">
SHOW REPLICA
STATUS
</code>
is more important than ensuring that it
returned the latest data.
</p>
<p>
If you issue this statement using the
<a class="link" href="mysql.html" title="6.5.1 mysql — The MySQL Command-Line Client">
<span class="command">
<strong>
mysql
</strong>
</span>
</a>
client, you can use a
<code class="literal">
\G
</code>
statement terminator
rather than a semicolon to obtain a more readable vertical
layout:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa89074407"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SHOW</span> <span class="token keyword">REPLICA</span> <span class="token keyword">STATUS</span>\G
<span class="token output"><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span> 1. row <span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span>
Replica_IO_State<span class="token punctuation">:</span> Waiting for source to send event
Source_Host<span class="token punctuation">:</span> 127.0.0.1
Source_User<span class="token punctuation">:</span> root
Source_Port<span class="token punctuation">:</span> 13000
Connect_Retry<span class="token punctuation">:</span> 1
Source_Log_File<span class="token punctuation">:</span> master-bin.000001
Read_Source_Log_Pos<span class="token punctuation">:</span> 927
Relay_Log_File<span class="token punctuation">:</span> slave-relay-bin.000002
Relay_Log_Pos<span class="token punctuation">:</span> 1145
Relay_Source_Log_File<span class="token punctuation">:</span> master-bin.000001
Replica_IO_Running<span class="token punctuation">:</span> Yes
Replica_SQL_Running<span class="token punctuation">:</span> Yes
Replicate_Do_DB<span class="token punctuation">:</span>
Replicate_Ignore_DB<span class="token punctuation">:</span>
Replicate_Do_Table<span class="token punctuation">:</span>
Replicate_Ignore_Table<span class="token punctuation">:</span>
Replicate_Wild_Do_Table<span class="token punctuation">:</span>
Replicate_Wild_Ignore_Table<span class="token punctuation">:</span>
Last_Errno<span class="token punctuation">:</span> 0
Last_Error<span class="token punctuation">:</span>
Skip_Counter<span class="token punctuation">:</span> 0
Exec_Source_Log_Pos<span class="token punctuation">:</span> 927
Relay_Log_Space<span class="token punctuation">:</span> 1355
Until_Condition<span class="token punctuation">:</span> None
Until_Log_File<span class="token punctuation">:</span>
Until_Log_Pos<span class="token punctuation">:</span> 0
Source_SSL_Allowed<span class="token punctuation">:</span> No
Source_SSL_CA_File<span class="token punctuation">:</span>
Source_SSL_CA_Path<span class="token punctuation">:</span>
Source_SSL_Cert<span class="token punctuation">:</span>
Source_SSL_Cipher<span class="token punctuation">:</span>
Source_SSL_Key<span class="token punctuation">:</span>
Seconds_Behind_Source<span class="token punctuation">:</span> 0
Source_SSL_Verify_Server_Cert<span class="token punctuation">:</span> No
Last_IO_Errno<span class="token punctuation">:</span> 0
Last_IO_Error<span class="token punctuation">:</span>
Last_SQL_Errno<span class="token punctuation">:</span> 0
Last_SQL_Error<span class="token punctuation">:</span>
Replicate_Ignore_Server_Ids<span class="token punctuation">:</span>
Source_Server_Id<span class="token punctuation">:</span> 1
Source_UUID<span class="token punctuation">:</span> 73f86016-978b-11ee-ade5-8d2a2a562feb
Source_Info_File<span class="token punctuation">:</span> mysql.slave_master_info
SQL_Delay<span class="token punctuation">:</span> 0
SQL_Remaining_Delay<span class="token punctuation">:</span> NULL
Replica_SQL_Running_State<span class="token punctuation">:</span> Replica has read all relay log; waiting for more updates
Source_Retry_Count<span class="token punctuation">:</span> 10
Source_Bind<span class="token punctuation">:</span>
Last_IO_Error_Timestamp<span class="token punctuation">:</span>
Last_SQL_Error_Timestamp<span class="token punctuation">:</span>
Source_SSL_Crl<span class="token punctuation">:</span>
Source_SSL_Crlpath<span class="token punctuation">:</span>
Retrieved_Gtid_Set<span class="token punctuation">:</span> 73f86016-978b-11ee-ade5-8d2a2a562feb<span class="token punctuation">:</span>1-3
Executed_Gtid_Set<span class="token punctuation">:</span> 73f86016-978b-11ee-ade5-8d2a2a562feb<span class="token punctuation">:</span>1-3
Auto_Position<span class="token punctuation">:</span> 1
Replicate_Rewrite_DB<span class="token punctuation">:</span>
Channel_Name<span class="token punctuation">:</span>
Source_TLS_Version<span class="token punctuation">:</span>
Source_public_key_path<span class="token punctuation">:</span>
Get_Source_public_key<span class="token punctuation">:</span> 0
Network_Namespace<span class="token punctuation">:</span></span></code></pre>
</div>
<p>
The Performance Schema provides tables that expose replication
information. This is similar to the information available from
the
<a class="link" href="show-replica-status.html" title="15.7.7.35 SHOW REPLICA STATUS Statement">
<code class="literal">
SHOW REPLICA STATUS
</code>
</a>
statement, but represented in table form. For details, see
<a class="xref" href="performance-schema-replication-tables.html" title="29.12.11 Performance Schema Replication Tables">
Section 29.12.11, “Performance Schema Replication Tables”
</a>
.
</p>
<p>
You can set the
<code class="literal">
GTID_ONLY
</code>
option for the
<a class="link" href="change-replication-source-to.html" title="15.4.2.2 CHANGE REPLICATION SOURCE TO Statement">
<code class="literal">
CHANGE REPLICATION SOURCE TO
</code>
</a>
statement to stop a replication channel from persisting file
names and file positions in the replication metadata
repositories. With this setting, file positions for the source
binary log file and the relay log file are tracked in memory.
The
<a class="link" href="show-replica-status.html" title="15.7.7.35 SHOW REPLICA STATUS Statement">
<code class="literal">
SHOW REPLICA STATUS
</code>
</a>
statement
still displays file positions in normal use. However, because
the file positions are not being regularly updated in the
connection metadata repository and the applier metadata
repository except in a few situations, they are likely to be out
of date if the server is restarted.
</p>
<p>
For a replication channel with the
<code class="literal">
GTID_ONLY
</code>
setting after a server start, the read and applied file
positions for the source binary log file
(
<code class="literal">
Read_Source_Log_Pos
</code>
and
<code class="literal">
Exec_Source_Log_Pos
</code>
) are set to zero, and the
file names (
<code class="literal">
Source_Log_File
</code>
and
<code class="literal">
Relay_Source_Log_File
</code>
) are set to
<code class="literal">
INVALID
</code>
. The relay log file name
(
<code class="literal">
Relay_Log_File
</code>
) is set according to the
relay_log_recovery setting, either a new file that was created
at server start or the first relay log file present. The file
position (
<code class="literal">
Relay_Log_Pos
</code>
) is set to position
4, and GTID auto-skip is used to skip any transactions in the
file that were already applied.
</p>
<p>
When the receiver thread contacts the source and gets valid
position information, the read position
(
<code class="literal">
Read_Source_Log_Pos
</code>
) and file name
(
<code class="literal">
Source_Log_File
</code>
) are updated with the
correct data and become valid. When the applier thread applies a
transaction from the source, or skips an already executed
transaction, the executed position
(
<code class="literal">
Exec_Source_Log_Pos
</code>
) and file name
(
<code class="literal">
Relay_Source_Log_File
</code>
) are updated with the
correct data and become valid. The relay log file position
(
<code class="literal">
Relay_Log_Pos
</code>
) is also updated at that time.
</p>
<p>
The following list describes the fields returned by
<a class="link" href="show-replica-status.html" title="15.7.7.35 SHOW REPLICA STATUS Statement">
<code class="literal">
SHOW
REPLICA STATUS
</code>
</a>
. For additional information about
interpreting their meanings, see
<a class="xref" href="replication-administration-status.html" title="19.1.7.1 Checking Replication Status">
Section 19.1.7.1, “Checking Replication Status”
</a>
.
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<code class="literal">
Replica_IO_State
</code>
</p>
<p>
A copy of the
<code class="literal">
State
</code>
field of the
<a class="link" href="show-processlist.html" title="15.7.7.31 SHOW PROCESSLIST Statement">
<code class="literal">
SHOW PROCESSLIST
</code>
</a>
output for
the replica I/O (receiver) thread. This tells you what the
thread is doing: trying to connect to the source, waiting
for events from the source, reconnecting to the source, and
so on. For a listing of possible states, see
<a class="xref" href="replica-io-thread-states.html" title="10.14.5 Replication I/O (Receiver) Thread States">
Section 10.14.5, “Replication I/O (Receiver) Thread States”
</a>
.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Source_Host
</code>
</p>
<p>
The source host that the replica is connected to.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Source_User
</code>
</p>
<p>
The user name of the account used to connect to the source.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Source_Port
</code>
</p>
<p>
The port used to connect to the source.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Connect_Retry
</code>
</p>
<p>
The number of seconds between connect retries (default 60).
This can be set with a
<a class="link" href="change-replication-source-to.html" title="15.4.2.2 CHANGE REPLICATION SOURCE TO Statement">
<code class="literal">
CHANGE
REPLICATION SOURCE TO
</code>
</a>
statement.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Source_Log_File
</code>
</p>
<p>
The name of the source binary log file from which the I/O
(receiver) thread is currently reading. This is set to
<code class="literal">
INVALID
</code>
for a replication channel with
the
<code class="literal">
GTID_ONLY
</code>
setting after a server
start. It will be updated when the replica contacts the
source.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Read_Source_Log_Pos
</code>
</p>
<p>
The position in the current source binary log file up to
which the I/O (receiver) thread has read. This is set to
zero for a replication channel with the
<code class="literal">
GTID_ONLY
</code>
setting after a server start.
It will be updated when the replica contacts the source.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Relay_Log_File
</code>
</p>
<p>
The name of the relay log file from which the SQL (applier)
thread is currently reading and executing.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Relay_Log_Pos
</code>
</p>
<p>
The position in the current relay log file up to which the
SQL (applier) thread has read and executed.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Relay_Source_Log_File
</code>
</p>
<p>
The name of the source binary log file containing the most
recent event executed by the SQL (applier) thread. This is
set to
<code class="literal">
INVALID
</code>
for a replication channel
with the
<code class="literal">
GTID_ONLY
</code>
setting after a server
start. It will be updated when a transaction is executed or
skipped.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Replica_IO_Running
</code>
</p>
<p>
Whether the replication I/O (receiver) thread is started and
has connected successfully to the source. Internally, the
state of this thread is represented by one of the following
three values:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
<b>
MYSQL_REPLICA_NOT_RUN.
</b>
The replication I/O (receiver) thread is not running.
For this state,
<code class="literal">
Replica_IO_Running
</code>
is
<code class="literal">
No
</code>
.
</p>
</li>
<li class="listitem">
<p>
<b>
MYSQL_REPLICA_RUN_NOT_CONNECT.
</b>
The replication I/O (receiver) thread is running, but
is not connected to a replication source. For this
state,
<code class="literal">
Replica_IO_Running
</code>
is
<code class="literal">
Connecting
</code>
.
</p>
</li>
<li class="listitem">
<p>
<b>
MYSQL_REPLICA_RUN_CONNECT.
</b>
The replication I/O (receiver) thread is running, and
is connected to a replication source. For this state,
<code class="literal">
Replica_IO_Running
</code>
is
<code class="literal">
Yes
</code>
.
</p>
</li>
</ul>
</div>
</li>
<li class="listitem">
<p>
<code class="literal">
Replica_SQL_Running
</code>
</p>
<p>
Whether the replication SQL (applier) thread is started.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Replicate_Do_DB
</code>
,
<code class="literal">
Replicate_Ignore_DB
</code>
</p>
<p>
The names of any databases that were specified with the
<a class="link" href="replication-options-replica.html#option_mysqld_replicate-do-db">
<code class="option">
--replicate-do-db
</code>
</a>
and
<a class="link" href="replication-options-replica.html#option_mysqld_replicate-ignore-db">
<code class="option">
--replicate-ignore-db
</code>
</a>
options, or the
<a class="link" href="change-replication-filter.html" title="15.4.2.1 CHANGE REPLICATION FILTER Statement">
<code class="literal">
CHANGE REPLICATION
FILTER
</code>
</a>
statement. If the
<code class="literal">
FOR
CHANNEL
</code>
clause was used, the channel specific
replication filters are shown. Otherwise, the replication
filters for every replication channel are shown.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Replicate_Do_Table
</code>
,
<code class="literal">
Replicate_Ignore_Table
</code>
,
<code class="literal">
Replicate_Wild_Do_Table
</code>
,
<code class="literal">
Replicate_Wild_Ignore_Table
</code>
</p>
<p>
The names of any tables that were specified with the
<a class="link" href="replication-options-replica.html#option_mysqld_replicate-do-table">
<code class="option">
--replicate-do-table
</code>
</a>
,
<a class="link" href="replication-options-replica.html#option_mysqld_replicate-ignore-table">
<code class="option">
--replicate-ignore-table
</code>
</a>
,
<a class="link" href="replication-options-replica.html#option_mysqld_replicate-wild-do-table">
<code class="option">
--replicate-wild-do-table
</code>
</a>
,
and
<a class="link" href="replication-options-replica.html#option_mysqld_replicate-wild-ignore-table">
<code class="option">
--replicate-wild-ignore-table
</code>
</a>
options, or the
<a class="link" href="change-replication-filter.html" title="15.4.2.1 CHANGE REPLICATION FILTER Statement">
<code class="literal">
CHANGE REPLICATION
FILTER
</code>
</a>
statement. If the
<code class="literal">
FOR
CHANNEL
</code>
clause was used, the channel specific
replication filters are shown. Otherwise, the replication
filters for every replication channel are shown.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Last_Errno
</code>
,
<code class="literal">
Last_Error
</code>
</p>
<p>
These columns are aliases for
<code class="literal">
Last_SQL_Errno
</code>
and
<code class="literal">
Last_SQL_Error
</code>
.
</p>
<p>
Issuing
<a class="link" href="reset-binary-logs-and-gtids.html" title="15.4.1.2 RESET BINARY LOGS AND GTIDS Statement">
<code class="literal">
RESET BINARY LOGS AND
GTIDS
</code>
</a>
or
<a class="link" href="reset-replica.html" title="15.4.2.3 RESET REPLICA Statement">
<code class="literal">
RESET
REPLICA
</code>
</a>
resets the values shown in these columns.
</p>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Note
</div>
<p>
When the replication SQL thread receives an error, it
reports the error first, then stops the SQL thread. This
means that there is a small window of time during which
<code class="literal">
SHOW REPLICA STATUS
</code>
shows a nonzero
value for
<code class="literal">
Last_SQL_Errno
</code>
even though
<code class="literal">
Replica_SQL_Running
</code>
still displays
<code class="literal">
Yes
</code>
.
</p>
</div>
</li>
<li class="listitem">
<p>
<code class="literal">
Skip_Counter
</code>
</p>
<p>
The current value of the
<a class="link" href="replication-options-replica.html#sysvar_sql_replica_skip_counter">
<code class="literal">
sql_replica_skip_counter
</code>
</a>
system variable.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Exec_Source_Log_Pos
</code>
</p>
<p>
The position in the current source binary log file to which
the replication SQL thread has read and executed, marking
the start of the next transaction or event to be processed.
This is set to zero for a replication channel with the
<code class="literal">
GTID_ONLY
</code>
setting after a server start.
It will be updated when a transaction is executed or
skipped.
</p>
<p>
You can use this value with the
<a class="link" href="change-replication-source-to.html" title="15.4.2.2 CHANGE REPLICATION SOURCE TO Statement">
<code class="literal">
CHANGE
REPLICATION SOURCE TO
</code>
</a>
statement's
<code class="literal">
SOURCE_LOG_POS
</code>
option when starting a new
replica from an existing replica, so that the new replica
reads from this point. The coordinates given by
(
<code class="literal">
Relay_Source_Log_File
</code>
,
<code class="literal">
Exec_Source_Log_Pos
</code>
) in the source's
binary log correspond to the coordinates given by
(
<code class="literal">
Relay_Log_File
</code>
,
<code class="literal">
Relay_Log_Pos
</code>
) in the relay log.
</p>
<p>
Inconsistencies in the sequence of transactions from the
relay log which have been executed can cause this value to
be a
<span class="quote">
“
<span class="quote">
low-water mark
</span>
”
</span>
. In other words,
transactions appearing before the position are guaranteed to
have committed, but transactions after the position may have
committed or not. If these gaps need to be corrected, use
<a class="link" href="start-replica.html" title="15.4.2.4 START REPLICA Statement">
<code class="literal">
START REPLICA
UNTIL SQL_AFTER_MTS_GAPS
</code>
</a>
. See
<a class="xref" href="replication-features-transaction-inconsistencies.html" title="19.5.1.34 Replication and Transaction Inconsistencies">
Section 19.5.1.34, “Replication and Transaction Inconsistencies”
</a>
for more information.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Relay_Log_Space
</code>
</p>
<p>
The total combined size of all existing relay log files.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Until_Condition
</code>
,
<code class="literal">
Until_Log_File
</code>
,
<code class="literal">
Until_Log_Pos
</code>
</p>
<p>
The values specified in the
<code class="literal">
UNTIL
</code>
clause
of the
<a class="link" href="start-replica.html" title="15.4.2.4 START REPLICA Statement">
<code class="literal">
START
REPLICA
</code>
</a>
statement.
</p>
<p>
<code class="literal">
Until_Condition
</code>
has these values:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
<code class="literal">
None
</code>
if no
<code class="literal">
UNTIL
</code>
clause was specified.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Source
</code>
if the replica is reading
until a given position in the source's binary log.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Relay
</code>
if the replica is reading until
a given position in its relay log.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
SQL_BEFORE_GTIDS
</code>
if the replication
SQL thread is processing transactions until it has
reached the first transaction whose GTID is listed in
the
<code class="literal">
gtid_set
</code>
.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
SQL_AFTER_GTIDS
</code>
if the replication
threads are processing all transactions until the last
transaction in the
<code class="literal">
gtid_set
</code>
has been
processed by both threads.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
SQL_AFTER_MTS_GAPS
</code>
if a multithreaded
replica's SQL threads are running until no more gaps are
found in the relay log.
</p>
</li>
</ul>
</div>
<p>
<code class="literal">
Until_Log_File
</code>
and
<code class="literal">
Until_Log_Pos
</code>
indicate the log file name
and position that define the coordinates at which the
replication SQL thread stops executing.
</p>
<p>
For more information on
<code class="literal">
UNTIL
</code>
clauses,
see
<a class="xref" href="start-replica.html" title="15.4.2.4 START REPLICA Statement">
Section 15.4.2.4, “START REPLICA Statement”
</a>
.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Source_SSL_Allowed
</code>
,
<code class="literal">
Source_SSL_CA_File
</code>
,
<code class="literal">
Source_SSL_CA_Path
</code>
,
<code class="literal">
Source_SSL_Cert
</code>
,
<code class="literal">
Source_SSL_Cipher
</code>
,
<code class="literal">
Source_SSL_CRL_File
</code>
,
<code class="literal">
Source_SSL_CRL_Path
</code>
,
<code class="literal">
Source_SSL_Key
</code>
,
<code class="literal">
Source_SSL_Verify_Server_Cert
</code>
</p>
<p>
These fields show the SSL parameters used by the replica to
connect to the source, if any.
</p>
<p>
<code class="literal">
Source_SSL_Allowed
</code>
has these values:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
<code class="literal">
Yes
</code>
if an SSL connection to the
source is permitted.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
No
</code>
if an SSL connection to the source
is not permitted.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Ignored
</code>
if an SSL connection is
permitted but the replica server does not have SSL
support enabled.
</p>
</li>
</ul>
</div>
<p>
The values of the other SSL-related fields correspond to the
values of the
<code class="literal">
SOURCE_SSL_*
</code>
options of the
<a class="link" href="change-replication-source-to.html" title="15.4.2.2 CHANGE REPLICATION SOURCE TO Statement">
<code class="literal">
CHANGE REPLICATION SOURCE TO
</code>
</a>
statement.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Seconds_Behind_Source
</code>
</p>
<p>
This field is an indication of how
<span class="quote">
“
<span class="quote">
late
</span>
”
</span>
the
replica is:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
When the replica is actively processing updates, this
field shows the difference between the current timestamp
on the replica and the original timestamp logged on the
source for the event currently being processed on the
replica.
</p>
</li>
<li class="listitem">
<p>
When no event is currently being processed on the
replica, this value is 0.
</p>
</li>
</ul>
</div>
<p>
In essence, this field measures the time difference in
seconds between the replication SQL (applier) thread and the
replication I/O (receiver) thread. If the network connection
between source and replica is fast, the replication receiver
thread is very close to the source, so this field is a good
approximation of how late the replication applier thread is
compared to the source. If the network is slow, this is
<span class="emphasis">
<em>
not
</em>
</span>
a good approximation; the
replication applier thread may quite often be caught up with
the slow-reading replication receiver thread, so
<code class="literal">
Seconds_Behind_Source
</code>
often shows a value
of 0, even if the replication receiver thread is late
compared to the source. In other words,
<span class="emphasis">
<em>
this
column is useful only for fast networks
</em>
</span>
.
</p>
<p>
This time difference computation works even if the source
and replica do not have identical clock times, provided that
the difference, computed when the replica receiver thread
starts, remains constant from then on. Any changes,
including NTP updates, can lead to clock skews that can make
calculation of
<code class="literal">
Seconds_Behind_Source
</code>
less
reliable.
</p>
<p>
In MySQL 8.4, this field is
<code class="literal">
NULL
</code>
(undefined or unknown) if the
replication applier thread is not running, or if the applier
thread has consumed all of the relay log and the replication
receiver thread is not running. (In older versions of MySQL,
this field was
<code class="literal">
NULL
</code>
if the replication
applier thread or the replication receiver thread was not
running or was not connected to the source.) If the
replication receiver thread is running but the relay log is
exhausted,
<code class="literal">
Seconds_Behind_Source
</code>
is set
to 0.
</p>
<p>
The value of
<code class="literal">
Seconds_Behind_Source
</code>
is
based on the timestamps stored in events, which are
preserved through replication. This means that if a source
M1 is itself a replica of M0, any event from M1's binary log
that originates from M0's binary log has M0's timestamp for
that event. This enables MySQL to replicate
<a class="link" href="datetime.html" title="13.2.2 The DATE, DATETIME, and TIMESTAMP Types">
<code class="literal">
TIMESTAMP
</code>
</a>
successfully.
However, the problem for
<code class="literal">
Seconds_Behind_Source
</code>
is that if M1 also
receives direct updates from clients, the
<code class="literal">
Seconds_Behind_Source
</code>
value randomly
fluctuates because sometimes the last event from M1
originates from M0 and sometimes is the result of a direct
update on M1.
</p>
<p>
When using a multithreaded replica, you should keep in mind
that this value is based on
<code class="literal">
Exec_Source_Log_Pos
</code>
, and so may not
reflect the position of the most recently committed
transaction.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Last_IO_Errno
</code>
,
<code class="literal">
Last_IO_Error
</code>
</p>
<p>
The error number and error message of the most recent error
that caused the replication I/O (receiver) thread to stop.
An error number of 0 and message of the empty string mean
<span class="quote">
“
<span class="quote">
no error.
</span>
”
</span>
If the
<code class="literal">
Last_IO_Error
</code>
value is not empty, the
error values also appear in the replica's error log.
</p>
<p>
I/O error information includes a timestamp showing when the
most recent I/O (receiver)thread error occurred. This
timestamp uses the format
<em class="replaceable">
<code>
YYMMDD
hh:mm:ss
</code>
</em>
, and appears in the
<code class="literal">
Last_IO_Error_Timestamp
</code>
column.
</p>
<p>
Issuing
<a class="link" href="reset-binary-logs-and-gtids.html" title="15.4.1.2 RESET BINARY LOGS AND GTIDS Statement">
<code class="literal">
RESET BINARY LOGS AND
GTIDS
</code>
</a>
or
<a class="link" href="reset-replica.html" title="15.4.2.3 RESET REPLICA Statement">
<code class="literal">
RESET
REPLICA
</code>
</a>
resets the values shown in these columns.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Last_SQL_Errno
</code>
,
<code class="literal">
Last_SQL_Error
</code>
</p>
<p>
The error number and error message of the most recent error
that caused the replication SQL (applier) thread to stop. An
error number of 0 and message of the empty string mean
<span class="quote">
“
<span class="quote">
no error.
</span>
”
</span>
If the
<code class="literal">
Last_SQL_Error
</code>
value is not empty, the
error values also appear in the replica's error log.
</p>
<p>
If the replica is multithreaded, the replication SQL thread
is the coordinator for worker threads. In this case, the
<code class="literal">
Last_SQL_Error
</code>
field shows exactly what
the
<code class="literal">
Last_Error_Message
</code>
column in the
Performance Schema
<a class="link" href="performance-schema-replication-applier-status-by-coordinator-table.html" title="29.12.11.6 The replication_applier_status_by_coordinator Table">
<code class="literal">
replication_applier_status_by_coordinator
</code>
</a>
table shows. The field value is modified to suggest that
there may be more failures in the other worker threads which
can be seen in the
<a class="link" href="performance-schema-replication-applier-status-by-worker-table.html" title="29.12.11.7 The replication_applier_status_by_worker Table">
<code class="literal">
replication_applier_status_by_worker
</code>
</a>
table that shows each worker thread's status. If that table
is not available, the replica error log can be used. The log
or the
<a class="link" href="performance-schema-replication-applier-status-by-worker-table.html" title="29.12.11.7 The replication_applier_status_by_worker Table">
<code class="literal">
replication_applier_status_by_worker
</code>
</a>
table should also be used to learn more about the failure
shown by
<a class="link" href="show-replica-status.html" title="15.7.7.35 SHOW REPLICA STATUS Statement">
<code class="literal">
SHOW
REPLICA STATUS
</code>
</a>
or the coordinator table.
</p>
<p>
SQL error information includes a timestamp showing when the
most recent SQL (applier) thread error occurred. This
timestamp uses the format
<em class="replaceable">
<code>
YYMMDD
hh:mm:ss
</code>
</em>
, and appears in the
<code class="literal">
Last_SQL_Error_Timestamp
</code>
column.
</p>
<p>
Issuing
<a class="link" href="reset-binary-logs-and-gtids.html" title="15.4.1.2 RESET BINARY LOGS AND GTIDS Statement">
<code class="literal">
RESET BINARY LOGS AND
GTIDS
</code>
</a>
or
<a class="link" href="reset-replica.html" title="15.4.2.3 RESET REPLICA Statement">
<code class="literal">
RESET
REPLICA
</code>
</a>
resets the values shown in these columns.
</p>
<p>
In MySQL 8.4, all error codes and messages
displayed in the
<code class="literal">
Last_SQL_Errno
</code>
and
<code class="literal">
Last_SQL_Error
</code>
columns correspond to
error values listed in
<a class="ulink" href="/doc/mysql-errors/8.4/en/server-error-reference.html" target="_top">
Server Error Message Reference
</a>
. This was not
always true in previous versions. (Bug #11760365, Bug
#52768)
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Replicate_Ignore_Server_Ids
</code>
</p>
<p>
Any server IDs that have been specified using the
<code class="literal">
IGNORE_SERVER_IDS
</code>
option of the
<a class="link" href="change-replication-source-to.html" title="15.4.2.2 CHANGE REPLICATION SOURCE TO Statement">
<code class="literal">
CHANGE REPLICATION SOURCE TO
</code>
</a>
statement, so that the replica ignores events from these
servers. This option is used in a circular or other
multi-source replication setup when one of the servers is
removed. If any server IDs have been set in this way, a
comma-delimited list of one or more numbers is shown. If no
server IDs have been set, the field is blank.
</p>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Note
</div>
<p>
The
<code class="literal">
Ignored_server_ids
</code>
value in the
<code class="literal">
slave_master_info
</code>
table also shows the
server IDs to be ignored, but as a space-delimited list,
preceded by the total number of server IDs to be ignored.
For example, if a
<a class="link" href="change-replication-source-to.html" title="15.4.2.2 CHANGE REPLICATION SOURCE TO Statement">
<code class="literal">
CHANGE REPLICATION
SOURCE TO
</code>
</a>
statement containing the
<code class="literal">
IGNORE_SERVER_IDS = (2,6,9)
</code>
option has
been issued to tell a replica to ignore sources having the
server ID 2, 6, or 9, that information appears as shown
here:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-none"><div class="docs-select-all right" id="sa35760093"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-none"> Replicate_Ignore_Server_Ids: 2, 6, 9</code></pre>
</div>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-none"><div class="docs-select-all right" id="sa85820072"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-none"> Ignored_server_ids: 3, 2, 6, 9</code></pre>
</div>
</div>
<p>
<code class="literal">
Replicate_Ignore_Server_Ids
</code>
filtering is
performed by the I/O (receiver) thread, rather than by the
SQL (applier) thread, which means that events which are
filtered out are not written to the relay log. This differs
from the filtering actions taken by server options such
<a class="link" href="replication-options-replica.html#option_mysqld_replicate-do-table">
<code class="option">
--replicate-do-table
</code>
</a>
, which
apply to the applier thread.
</p>
<p>
If
<code class="literal">
SET gtid_mode=ON
</code>
is issued when any
channel has existing server IDs set with
<a class="link" href="change-replication-source-to.html#crs-opt-ignore_server_ids">
<code class="literal">
IGNORE_SERVER_IDS
</code>
</a>
, the
statement is rejected with an error. Before starting
GTID-based replication, use
<a class="link" href="show-replica-status.html" title="15.7.7.35 SHOW REPLICA STATUS Statement">
<code class="literal">
SHOW
REPLICA STATUS
</code>
</a>
to check for and clear all ignored
server ID lists on the servers involved. You can clear a
list by issuing a
<a class="link" href="change-replication-source-to.html" title="15.4.2.2 CHANGE REPLICATION SOURCE TO Statement">
<code class="literal">
CHANGE REPLICATION
SOURCE TO
</code>
</a>
statement using
<code class="literal">
IGNORE_SERVER_IDS=()
</code>
—that is, with
an empty list of server IDs.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Source_Server_Id
</code>
</p>
<p>
The
<a class="link" href="replication-options.html#sysvar_server_id">
<code class="literal">
server_id
</code>
</a>
value from
the source.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Source_UUID
</code>
</p>
<p>
The
<a class="link" href="replication-options.html#sysvar_server_uuid">
<code class="literal">
server_uuid
</code>
</a>
value from
the source.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Source_Info_File
</code>
</p>
<p>
The location of the
<code class="filename">
master.info
</code>
file,
the use of which is now deprecated. By default, a table is
used instead for the replica's connection metadata
repository.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
SQL_Delay
</code>
</p>
<p>
The number of seconds that the replica must lag the source.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
SQL_Remaining_Delay
</code>
</p>
<p>
When
<code class="literal">
Replica_SQL_Running_State
</code>
is
<code class="literal">
Waiting until SOURCE_DELAY seconds after source
executed event
</code>
, this field contains the number of
delay seconds remaining. At other times, this field is
<code class="literal">
NULL
</code>
.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Replica_SQL_Running_State
</code>
</p>
<p>
The state of the SQL thread (analogous to
<code class="literal">
Replica_IO_State
</code>
). The value is identical
to the
<code class="literal">
State
</code>
value of the SQL thread as
displayed by
<a class="link" href="show-processlist.html" title="15.7.7.31 SHOW PROCESSLIST Statement">
<code class="literal">
SHOW
PROCESSLIST
</code>
</a>
.
<a class="xref" href="replica-sql-thread-states.html" title="10.14.6 Replication SQL Thread States">
Section 10.14.6, “Replication SQL Thread States”
</a>
, provides a
listing of possible states.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Source_Retry_Count
</code>
</p>
<p>
The number of times the replica can attempt to reconnect to
the source in the event of a lost connection. This value can
be set using the
<code class="literal">
SOURCE_RETRY_COUNT
</code>
option of the
<a class="link" href="change-replication-source-to.html" title="15.4.2.2 CHANGE REPLICATION SOURCE TO Statement">
<code class="literal">
CHANGE REPLICATION SOURCE
TO
</code>
</a>
statement.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Source_Bind
</code>
</p>
<p>
The network interface that the replica is bound to, if any.
This is set using the
<code class="literal">
SOURCE_BIND
</code>
option
for the
<a class="link" href="change-replication-source-to.html" title="15.4.2.2 CHANGE REPLICATION SOURCE TO Statement">
<code class="literal">
CHANGE REPLICATION SOURCE
TO
</code>
</a>
statement.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Last_IO_Error_Timestamp
</code>
</p>
<p>
A timestamp in
<em class="replaceable">
<code>
YYMMDD hh:mm:ss
</code>
</em>
format that shows when the most recent I/O error took place.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Last_SQL_Error_Timestamp
</code>
</p>
<p>
A timestamp in
<em class="replaceable">
<code>
YYMMDD hh:mm:ss
</code>
</em>
format that shows when the most recent SQL error occurred.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Retrieved_Gtid_Set
</code>
</p>
<p>
The set of global transaction IDs corresponding to all
transactions received by this replica. Empty if GTIDs are
not in use. See
<a class="xref" href="replication-gtids-concepts.html#replication-gtids-concepts-gtid-sets" title="GTID Sets">
GTID Sets
</a>
for
more information.
</p>
<p>
This is the set of all GTIDs that exist or have existed in
the relay logs. Each GTID is added as soon as the
<code class="literal">
Gtid_log_event
</code>
is received. This can
cause partially transmitted transactions to have their GTIDs
included in the set.
</p>
<p>
When all relay logs are lost due to executing
<a class="link" href="reset-replica.html" title="15.4.2.3 RESET REPLICA Statement">
<code class="literal">
RESET REPLICA
</code>
</a>
or
<a class="link" href="change-replication-source-to.html" title="15.4.2.2 CHANGE REPLICATION SOURCE TO Statement">
<code class="literal">
CHANGE REPLICATION SOURCE TO
</code>
</a>
,
or due to the effects of the
<a class="link" href="replication-options-replica.html#sysvar_relay_log_recovery">
<code class="option">
--relay-log-recovery
</code>
</a>
option,
the set is cleared. When
<a class="link" href="replication-options-replica.html#sysvar_relay_log_purge">
<code class="literal">
relay_log_purge = 1
</code>
</a>
, the
newest relay log is always kept, and the set is not cleared.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Executed_Gtid_Set
</code>
</p>
<p>
The set of global transaction IDs written in the binary log.
This is the same as the value for the global
<a class="link" href="replication-options-gtids.html#sysvar_gtid_executed">
<code class="literal">
gtid_executed
</code>
</a>
system
variable on this server, as well as the value for
<code class="literal">
Executed_Gtid_Set
</code>
in the output of
<a class="link" href="show-binary-log-status.html" title="15.7.7.1 SHOW BINARY LOG STATUS Statement">
<code class="literal">
SHOW BINARY LOG STATUS
</code>
</a>
on
this server. Empty if GTIDs are not in use. See
<a class="xref" href="replication-gtids-concepts.html#replication-gtids-concepts-gtid-sets" title="GTID Sets">
GTID Sets
</a>
for
more information.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Auto_Position
</code>
</p>
<p>
1 if GTID auto-positioning is in use for the channel,
otherwise 0.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Replicate_Rewrite_DB
</code>
</p>
<p>
The
<code class="literal">
Replicate_Rewrite_DB
</code>
value displays
any replication filtering rules that were specified. For
example, if the following replication filter rule was set:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-sql"><div class="docs-select-all right" id="sa91261178"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">CHANGE</span> <span class="token keyword">REPLICATION</span> <span class="token keyword">FILTER</span> <span class="token keyword">REPLICATE_REWRITE_DB</span><span class="token operator">=</span><span class="token punctuation">(</span><span class="token punctuation">(</span>db1<span class="token punctuation">,</span>db2<span class="token punctuation">)</span><span class="token punctuation">,</span> <span class="token punctuation">(</span>db3<span class="token punctuation">,</span>db4<span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
the
<code class="literal">
Replicate_Rewrite_DB
</code>
value displays:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-none"><div class="docs-select-all right" id="sa18977488"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-none">Replicate_Rewrite_DB: (db1,db2),(db3,db4)</code></pre>
</div>
<p>
For more information, see
<a class="xref" href="change-replication-filter.html" title="15.4.2.1 CHANGE REPLICATION FILTER Statement">
Section 15.4.2.1, “CHANGE REPLICATION FILTER Statement”
</a>
.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Channel_name
</code>
</p>
<p>
The replication channel which is being displayed. There is
always a default replication channel, and more replication
channels can be added. See
<a class="xref" href="replication-channels.html" title="19.2.2 Replication Channels">
Section 19.2.2, “Replication Channels”
</a>
for more information.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Master_TLS_Version
</code>
</p>
<p>
The TLS version used on the source. For TLS version
information, see
<a class="xref" href="encrypted-connection-protocols-ciphers.html" title="8.3.2 Encrypted Connection TLS Protocols and Ciphers">
Section 8.3.2, “Encrypted Connection TLS Protocols and Ciphers”
</a>
.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Source_public_key_path
</code>
</p>
<p>
The path name to a file containing a replica-side copy of
the public key required by the source for RSA key pair-based
password exchange. The file must be in PEM format. This
column applies to replicas that authenticate with the
<code class="literal">
sha256_password
</code>
(deprecated) or
<code class="literal">
caching_sha2_password
</code>
authentication
plugin.
</p>
<p>
If
<code class="literal">
Source_public_key_path
</code>
is given and
specifies a valid public key file, it takes precedence over
<code class="literal">
Get_source_public_key
</code>
.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Get_source_public_key
</code>
</p>
<p>
Whether to request from the source the public key required
for RSA key pair-based password exchange. This column
applies to replicas that authenticate with the
<code class="literal">
caching_sha2_password
</code>
authentication
plugin. For that plugin, the source does not send the public
key unless requested.
</p>
<p>
If
<code class="literal">
Source_public_key_path
</code>
is given and
specifies a valid public key file, it takes precedence over
<code class="literal">
Get_source_public_key
</code>
.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Network_Namespace
</code>
</p>
<p>
The network namespace name; empty if the connection uses the
default (global) namespace. For information about network
namespaces, see
<a class="xref" href="network-namespace-support.html" title="7.1.14 Network Namespace Support">
Section 7.1.14, “Network Namespace Support”
</a>
.
</p>
</li>
</ul>
</div>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/problems-with-mysql-sock.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="problems-with-mysql-sock">
</a>
B.3.3.6 How to Protect or Change the MySQL Unix Socket File
</h4>
</div>
</div>
</div>
<a class="indexterm" name="idm46045053781216">
</a>
<a class="indexterm" name="idm46045053779728">
</a>
<p>
The default location for the Unix socket file that the server
uses for communication with local clients is
<code class="filename">
/tmp/mysql.sock
</code>
. (For some distribution
formats, the directory might be different, such as
<code class="filename">
/var/lib/mysql
</code>
for RPMs.)
</p>
<p>
On some versions of Unix, anyone can delete files in the
<code class="filename">
/tmp
</code>
directory or other similar
directories used for temporary files. If the socket file is
located in such a directory on your system, this might cause
problems.
</p>
<p>
On most versions of Unix, you can protect your
<code class="filename">
/tmp
</code>
directory so that files can be
deleted only by their owners or the superuser
(
<code class="literal">
root
</code>
). To do this, set the
<code class="literal">
sticky
</code>
bit on the
<code class="filename">
/tmp
</code>
directory by logging in as
<code class="literal">
root
</code>
and using
the following command:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-terminal"><div class="docs-select-all right" id="sa54509392"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal"><span class="token prompt">$> </span><span class="token command">chmod</span> +t /tmp</code></pre>
</div>
<p>
You can check whether the
<code class="literal">
sticky
</code>
bit is set
by executing
<code class="literal">
ls -ld /tmp
</code>
. If the last
permission character is
<code class="literal">
t
</code>
, the bit is set.
</p>
<a class="indexterm" name="idm46045053766368">
</a>
<p>
Another approach is to change the place where the server
creates the Unix socket file. If you do this, you should also
let client programs know the new location of the file. You can
specify the file location in several ways:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
Specify the path in a global or local option file. For
example, put the following lines in
<code class="literal">
/etc/my.cnf
</code>
:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-ini"><div class="docs-select-all right" id="sa47352996"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-ini"><span class="token selector">[mysqld]</span>
<span class="token constant">socket</span><span class="token attr-value"><span class="token punctuation">=</span>/path/to/socket</span>
<span class="token selector">[client]</span>
<span class="token constant">socket</span><span class="token attr-value"><span class="token punctuation">=</span>/path/to/socket</span></code></pre>
</div>
<p>
See
<a class="xref" href="option-files.html" title="6.2.2.2 Using Option Files">
Section 6.2.2.2, “Using Option Files”
</a>
.
</p>
</li>
<li class="listitem">
<p>
Specify a
<a class="link" href="connection-options.html#option_general_socket">
<code class="option">
--socket
</code>
</a>
option
on the command line to
<a class="link" href="mysqld-safe.html" title="6.3.2 mysqld_safe — MySQL Server Startup Script">
<span class="command">
<strong>
mysqld_safe
</strong>
</span>
</a>
and
when you run client programs.
</p>
</li>
<li class="listitem">
<p>
Set the
<code class="literal">
MYSQL_UNIX_PORT
</code>
environment
variable to the path of the Unix socket file.
</p>
</li>
<li class="listitem">
<p>
Recompile MySQL from source to use a different default
Unix socket file location. Define the path to the file
with the
<a class="link" href="source-configuration-options.html#option_cmake_mysql_unix_addr">
<code class="option">
MYSQL_UNIX_ADDR
</code>
</a>
option when you run
<span class="command">
<strong>
CMake
</strong>
</span>
. See
<a class="xref" href="source-configuration-options.html" title="2.8.7 MySQL Source-Configuration Options">
Section 2.8.7, “MySQL Source-Configuration Options”
</a>
.
</p>
</li>
</ul>
</div>
<p>
You can test whether the new socket location works by
attempting to connect to the server with this command:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-terminal"><div class="docs-select-all right" id="sa63326971"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal"><span class="token prompt">$> </span><span class="token command">mysqladmin</span> <span class="token constant">--socket</span><span class="token attr-value"><span class="token punctuation">=</span>/path/to/socket</span> version</code></pre>
</div>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/alter-table-problems.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="alter-table-problems">
</a>
B.3.6.1 Problems with ALTER TABLE
</h4>
</div>
</div>
</div>
<a class="indexterm" name="idm46045053376064">
</a>
<a class="indexterm" name="idm46045053375024">
</a>
<a class="indexterm" name="idm46045053373536">
</a>
<a class="indexterm" name="idm46045053372048">
</a>
<p>
If you get a duplicate-key error when using
<a class="link" href="alter-table.html" title="15.1.9 ALTER TABLE Statement">
<code class="literal">
ALTER TABLE
</code>
</a>
to change the
character set or collation of a character column, the cause is
either that the new column collation maps two keys to the same
value or that the table is corrupted. In the latter case, you
should run
<a class="link" href="repair-table.html" title="15.7.3.5 REPAIR TABLE Statement">
<code class="literal">
REPAIR TABLE
</code>
</a>
on the
table.
<a class="link" href="repair-table.html" title="15.7.3.5 REPAIR TABLE Statement">
<code class="literal">
REPAIR TABLE
</code>
</a>
works for
<code class="literal">
MyISAM
</code>
,
<code class="literal">
ARCHIVE
</code>
, and
<code class="literal">
CSV
</code>
tables.
</p>
<p>
If you use
<a class="link" href="alter-table.html" title="15.1.9 ALTER TABLE Statement">
<code class="literal">
ALTER TABLE
</code>
</a>
on a
transactional table or if you are using Windows,
<a class="link" href="alter-table.html" title="15.1.9 ALTER TABLE Statement">
<code class="literal">
ALTER TABLE
</code>
</a>
unlocks the table
if you had done a
<a class="link" href="lock-tables.html" title="15.3.6 LOCK TABLES and UNLOCK TABLES Statements">
<code class="literal">
LOCK
TABLE
</code>
</a>
on it. This is done because
<code class="literal">
InnoDB
</code>
and these operating systems cannot
drop a table that is in use.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-programs-ndb-print-file.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="mysql-cluster-programs-ndb-print-file">
</a>
25.5.18 ndb_print_file — Print NDB Disk Data File Contents
</h3>
</div>
</div>
</div>
<a class="indexterm" name="idm46045100177968">
</a>
<p>
<a class="link" href="mysql-cluster-programs-ndb-print-file.html" title="25.5.18 ndb_print_file — Print NDB Disk Data File Contents">
<span class="command">
<strong>
ndb_print_file
</strong>
</span>
</a>
obtains information from an
NDB Cluster Disk Data file.
</p>
<h4>
<a name="idm46045100175136">
</a>
Usage
</h4>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-terminal"><div class="docs-select-all right" id="sa42513931"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal">ndb_print_file <span class="token punctuation">[</span><span class="token property">-v</span><span class="token punctuation">]</span> <span class="token punctuation">[</span><span class="token property">-q</span><span class="token punctuation">]</span> <em class="replaceable">file_name</em>+</code></pre>
</div>
<p>
<em class="replaceable">
<code>
file_name
</code>
</em>
is the name of an NDB
Cluster Disk Data file. Multiple filenames are accepted,
separated by spaces.
</p>
<p>
Like
<a class="link" href="mysql-cluster-programs-ndb-print-schema-file.html" title="25.5.20 ndb_print_schema_file — Print NDB Schema File Contents">
<span class="command">
<strong>
ndb_print_schema_file
</strong>
</span>
</a>
and
<a class="link" href="mysql-cluster-programs-ndb-print-sys-file.html" title="25.5.21 ndb_print_sys_file — Print NDB System File Contents">
<span class="command">
<strong>
ndb_print_sys_file
</strong>
</span>
</a>
(and unlike most of the
other
<a class="link" href="mysql-cluster.html" title="Chapter 25 MySQL NDB Cluster 8.4">
<code class="literal">
NDB
</code>
</a>
utilities that are
intended to be run on a management server host or to connect to
a management server)
<a class="link" href="mysql-cluster-programs-ndb-print-file.html" title="25.5.18 ndb_print_file — Print NDB Disk Data File Contents">
<span class="command">
<strong>
ndb_print_file
</strong>
</span>
</a>
must be
run on an NDB Cluster data node, since it accesses the data node
file system directly. Because it does not make use of the
management server, this utility can be used when the management
server is not running, and even when the cluster has been
completely shut down.
</p>
<h4>
<a name="idm46045100166096">
</a>
Options
</h4>
<p>
</p>
<p>
<a class="link" href="mysql-cluster-programs-ndb-print-file.html" title="25.5.18 ndb_print_file — Print NDB Disk Data File Contents">
<span class="command">
<strong>
ndb_print_file
</strong>
</span>
</a>
supports the following
options:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<a name="option_ndb_print_file_file-key">
</a>
<a class="link" href="mysql-cluster-programs-ndb-print-file.html#option_ndb_print_file_file-key">
<code class="option">
--file-key
</code>
</a>
,
<code class="option">
-K
</code>
</p>
<a class="indexterm" name="idm46045100160448">
</a>
<a class="indexterm" name="idm46045100158960">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for file-key">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--file-key=hex_data
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Supply file system encryption or decryption key from
<code class="literal">
stdin
</code>
,
<code class="literal">
tty
</code>
, or a
<code class="filename">
my.cnf
</code>
file.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_print_file_file-key-from-stdin">
</a>
<a class="link" href="mysql-cluster-programs-ndb-print-file.html#option_ndb_print_file_file-key-from-stdin">
<code class="option">
--file-key-from-stdin
</code>
</a>
</p>
<a class="indexterm" name="idm46045100147072">
</a>
<a class="indexterm" name="idm46045100145568">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for file-key-from-stdin">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--file-key-from-stdin
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Boolean
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
FALSE
</code>
</td>
</tr>
<tr>
<th>
Valid Values
</th>
<td>
<code class="literal">
TRUE
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Supply file system encryption or decryption key from
<code class="literal">
stdin
</code>
.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_print_file_help">
</a>
<a class="link" href="mysql-cluster-programs-ndb-print-file.html#option_ndb_print_file_help">
<code class="option">
--help
</code>
</a>
,
<code class="option">
-h
</code>
,
<code class="option">
-?
</code>
</p>
<a class="indexterm" name="idm46045100127312">
</a>
<a class="indexterm" name="idm46045100125824">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for help">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--help
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Print help message and exit.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_print_file_quiet">
</a>
<a class="link" href="mysql-cluster-programs-ndb-print-file.html#option_ndb_print_file_quiet">
<code class="option">
--quiet
</code>
</a>
,
<code class="option">
-q
</code>
</p>
<a class="indexterm" name="idm46045100115600">
</a>
<a class="indexterm" name="idm46045100114112">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for quiet">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--quiet
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Suppress output (quiet mode).
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_print_file_usage">
</a>
<a class="link" href="mysql-cluster-programs-ndb-print-file.html#option_ndb_print_file_usage">
<code class="option">
--usage
</code>
</a>
,
<code class="option">
-?
</code>
</p>
<a class="indexterm" name="idm46045100103952">
</a>
<a class="indexterm" name="idm46045100102464">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for usage">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--usage
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Print help message and exit.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_print_file_verbose">
</a>
<a class="link" href="mysql-cluster-programs-ndb-print-file.html#option_ndb_print_file_verbose">
<code class="option">
--verbose
</code>
</a>
,
<code class="option">
-v
</code>
</p>
<a class="indexterm" name="idm46045100092368">
</a>
<a class="indexterm" name="idm46045100090880">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for verbose">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--verbose
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Make output verbose.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_print_file_version">
</a>
<a class="link" href="mysql-cluster-programs-ndb-print-file.html#option_ndb_print_file_version">
<code class="option">
--version
</code>
</a>
,
<code class="option">
-v
</code>
</p>
<a class="indexterm" name="idm46045100080720">
</a>
<a class="indexterm" name="idm46045100079232">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for version">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--version
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Print version information and exit.
</p>
</li>
</ul>
</div>
<p>
For more information, see
<a class="xref" href="mysql-cluster-disk-data.html" title="25.6.11 NDB Cluster Disk Data Tables">
Section 25.6.11, “NDB Cluster Disk Data Tables”
</a>
.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/mysql-shell-tutorial-javascript.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h2 class="title">
<a name="mysql-shell-tutorial-javascript">
</a>
22.3 JavaScript Quick-Start Guide: MySQL Shell for Document Store
</h2>
</div>
</div>
</div>
<div class="toc">
<dl class="toc">
<dt>
<span class="section">
<a href="mysql-shell-tutorial-javascript-shell.html">
22.3.1 MySQL Shell
</a>
</span>
</dt>
<dt>
<span class="section">
<a href="mysql-shell-tutorial-javascript-download.html">
22.3.2 Download and Import world_x Database
</a>
</span>
</dt>
<dt>
<span class="section">
<a href="mysql-shell-tutorial-javascript-documents-collections.html">
22.3.3 Documents and Collections
</a>
</span>
</dt>
<dt>
<span class="section">
<a href="mysql-shell-tutorial-javascript-relational-tables.html">
22.3.4 Relational Tables
</a>
</span>
</dt>
<dt>
<span class="section">
<a href="mysql-shell-tutorial-javascript-documents-in-tables.html">
22.3.5 Documents in Tables
</a>
</span>
</dt>
</dl>
</div>
<a class="indexterm" name="idm46045128124800">
</a>
<p>
This quick-start guide provides instructions to begin prototyping
document store applications interactively with MySQL Shell. The
guide includes the following topics:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
Introduction to MySQL functionality, MySQL Shell, and the
<code class="literal">
world_x
</code>
example schema.
</p>
</li>
<li class="listitem">
<p>
Operations to manage collections and documents.
</p>
</li>
<li class="listitem">
<p>
Operations to manage relational tables.
</p>
</li>
<li class="listitem">
<p>
Operations that apply to documents within tables.
</p>
</li>
</ul>
</div>
<p>
To follow this quick-start guide you need a MySQL server with
X Plugin installed, the default in 8.4, and
MySQL Shell to use as the client.
<a class="ulink" href="/doc/mysql-shell/8.4/en/" target="_top">
MySQL Shell 8.4
</a>
provides more in-depth information about MySQL Shell. The Document
Store is accessed using X DevAPI, and MySQL Shell provides this
API in both JavaScript and Python.
</p>
<h3>
<a name="idm46045128117216">
</a>
Related Information
</h3>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<a class="ulink" href="/doc/mysql-shell/8.4/en/" target="_top">
MySQL Shell 8.4
</a>
provides more in-depth information
about MySQL Shell.
</p>
</li>
<li class="listitem">
<p>
See
<a class="ulink" href="/doc/mysql-shell/8.4/en/mysql-shell-install.html" target="_top">
Installing MySQL Shell
</a>
and
<a class="xref" href="x-plugin.html" title="22.5 X Plugin">
Section 22.5, “X Plugin”
</a>
for more information about the tools
used in this quick-start guide.
</p>
</li>
<li class="listitem">
<p>
<a class="ulink" href="/doc/x-devapi-userguide/en/" target="_top">
X DevAPI User Guide
</a>
provides more examples of
using X DevAPI to develop applications which use Document
Store.
</p>
</li>
<li class="listitem">
<p>
A
<a class="link" href="mysql-shell-tutorial-python.html" title="22.4 Python Quick-Start Guide: MySQL Shell for Document Store">
Python
</a>
quick-start guide is also available.
</p>
</li>
</ul>
</div>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-startup-configuration.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h2 class="title">
<a name="performance-schema-startup-configuration">
</a>
29.3 Performance Schema Startup Configuration
</h2>
</div>
</div>
</div>
<p>
To use the MySQL Performance Schema, it must be enabled at server
startup to enable event collection to occur.
</p>
<p>
The Performance Schema is enabled by default. To enable or disable
it explicitly, start the server with the
<a class="link" href="performance-schema-system-variables.html#sysvar_performance_schema">
<code class="literal">
performance_schema
</code>
</a>
variable set
to an appropriate value. For example, use these lines in the
server
<code class="filename">
my.cnf
</code>
file:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-ini"><div class="docs-select-all right" id="sa3353001"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-ini"><span class="token selector">[mysqld]</span>
<span class="token constant">performance_schema</span><span class="token attr-value"><span class="token punctuation">=</span>ON</span></code></pre>
</div>
<p>
If the server is unable to allocate any internal buffer during
Performance Schema initialization, the Performance Schema disables
itself and sets
<a class="link" href="performance-schema-system-variables.html#sysvar_performance_schema">
<code class="literal">
performance_schema
</code>
</a>
to
<code class="literal">
OFF
</code>
, and the server runs without
instrumentation.
</p>
<p>
The Performance Schema also permits instrument and consumer
configuration at server startup.
</p>
<p>
To control an instrument at server startup, use an option of this
form:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-terminal"><div class="docs-select-all right" id="sa33585571"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal"><span class="token constant">--performance-schema-instrument</span>=<span class="token atrule">'<em class="replaceable">instrument_name</em>=<em class="replaceable">value</em>'</span></code></pre>
</div>
<p>
Here,
<em class="replaceable">
<code>
instrument_name
</code>
</em>
is an instrument
name such as
<code class="literal">
wait/synch/mutex/sql/LOCK_open
</code>
,
and
<em class="replaceable">
<code>
value
</code>
</em>
is one of these values:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<code class="literal">
OFF
</code>
,
<code class="literal">
FALSE
</code>
, or
<code class="literal">
0
</code>
: Disable the instrument
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
ON
</code>
,
<code class="literal">
TRUE
</code>
, or
<code class="literal">
1
</code>
: Enable and time the instrument
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
COUNTED
</code>
: Enable and count (rather than
time) the instrument
</p>
</li>
</ul>
</div>
<p>
Each
<a class="link" href="performance-schema-options.html#option_mysqld_performance-schema-instrument">
<code class="option">
--performance-schema-instrument
</code>
</a>
option can specify only one instrument name, but multiple
instances of the option can be given to configure multiple
instruments. In addition, patterns are permitted in instrument
names to configure instruments that match the pattern. To
configure all condition synchronization instruments as enabled and
counted, use this option:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-terminal"><div class="docs-select-all right" id="sa32280601"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal"><span class="token constant">--performance-schema-instrument</span>=<span class="token atrule">'wait/synch/cond/%=COUNTED'</span></code></pre>
</div>
<p>
To disable all instruments, use this option:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-terminal"><div class="docs-select-all right" id="sa89629005"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal"><span class="token constant">--performance-schema-instrument</span>=<span class="token atrule">'%=OFF'</span></code></pre>
</div>
<p>
Exception: The
<code class="literal">
memory/performance_schema/%
</code>
instruments are built in and cannot be disabled at startup.
</p>
<p>
Longer instrument name strings take precedence over shorter
pattern names, regardless of order. For information about
specifying patterns to select instruments, see
<a class="xref" href="performance-schema-filtering-names.html" title="29.4.9 Naming Instruments or Consumers for Filtering Operations">
Section 29.4.9, “Naming Instruments or Consumers for Filtering Operations”
</a>
.
</p>
<p>
An unrecognized instrument name is ignored. It is possible that a
plugin installed later may create the instrument, at which time
the name is recognized and configured.
</p>
<p>
To control a consumer at server startup, use an option of this
form:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-terminal"><div class="docs-select-all right" id="sa70276416"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal"><span class="token constant">--performance-schema-consumer-<em class="replaceable">consumer_name</em></span><span class="token attr-value"><span class="token punctuation">=</span><em class="replaceable">value</em></span></code></pre>
</div>
<p>
Here,
<em class="replaceable">
<code>
consumer_name
</code>
</em>
is a consumer name
such as
<code class="literal">
events_waits_history
</code>
, and
<em class="replaceable">
<code>
value
</code>
</em>
is one of these values:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<code class="literal">
OFF
</code>
,
<code class="literal">
FALSE
</code>
, or
<code class="literal">
0
</code>
: Do not collect events for the consumer
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
ON
</code>
,
<code class="literal">
TRUE
</code>
, or
<code class="literal">
1
</code>
: Collect events for the consumer
</p>
</li>
</ul>
</div>
<p>
For example, to enable the
<code class="literal">
events_waits_history
</code>
consumer, use this option:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-terminal"><div class="docs-select-all right" id="sa85533066"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal"><span class="token constant">--performance-schema-consumer-events-waits-history</span><span class="token attr-value"><span class="token punctuation">=</span>ON</span></code></pre>
</div>
<p>
The permitted consumer names can be found by examining the
<a class="link" href="performance-schema-setup-consumers-table.html" title="29.12.2.2 The setup_consumers Table">
<code class="literal">
setup_consumers
</code>
</a>
table. Patterns are
not permitted. Consumer names in the
<a class="link" href="performance-schema-setup-consumers-table.html" title="29.12.2.2 The setup_consumers Table">
<code class="literal">
setup_consumers
</code>
</a>
table use
underscores, but for consumers set at startup, dashes and
underscores within the name are equivalent.
</p>
<p>
The Performance Schema includes several system variables that
provide configuration information:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa48648073"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SHOW</span> <span class="token keyword">VARIABLES</span> <span class="token operator">LIKE</span> <span class="token string">'perf%'</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> Variable_name <span class="token punctuation">|</span> Value <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> performance_schema <span class="token punctuation">|</span> ON <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> performance_schema_accounts_size <span class="token punctuation">|</span> 100 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> performance_schema_digests_size <span class="token punctuation">|</span> 200 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> performance_schema_events_stages_history_long_size <span class="token punctuation">|</span> 10000 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> performance_schema_events_stages_history_size <span class="token punctuation">|</span> 10 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> performance_schema_events_statements_history_long_size <span class="token punctuation">|</span> 10000 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> performance_schema_events_statements_history_size <span class="token punctuation">|</span> 10 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> performance_schema_events_waits_history_long_size <span class="token punctuation">|</span> 10000 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> performance_schema_events_waits_history_size <span class="token punctuation">|</span> 10 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> performance_schema_hosts_size <span class="token punctuation">|</span> 100 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> performance_schema_max_cond_classes <span class="token punctuation">|</span> 80 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> performance_schema_max_cond_instances <span class="token punctuation">|</span> 1000 <span class="token punctuation">|</span></span>
<span class="token punctuation">.</span><span class="token punctuation">.</span><span class="token punctuation">.</span></code></pre>
</div>
<p>
The
<a class="link" href="performance-schema-system-variables.html#sysvar_performance_schema">
<code class="literal">
performance_schema
</code>
</a>
variable
is
<code class="literal">
ON
</code>
or
<code class="literal">
OFF
</code>
to indicate
whether the Performance Schema is enabled or disabled. The other
variables indicate table sizes (number of rows) or memory
allocation values.
</p>
<a class="indexterm" name="idm46045075647328">
</a>
<a class="indexterm" name="idm46045075645840">
</a>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Note
</div>
<p>
With the Performance Schema enabled, the number of Performance
Schema instances affects the server memory footprint, perhaps to
a large extent. The Performance Schema autoscales many
parameters to use memory only as required; see
<a class="xref" href="performance-schema-memory-model.html" title="29.17 The Performance Schema Memory-Allocation Model">
Section 29.17, “The Performance Schema Memory-Allocation Model”
</a>
.
</p>
</div>
<p>
To change the value of Performance Schema system variables, set
them at server startup. For example, put the following lines in a
<code class="filename">
my.cnf
</code>
file to change the sizes of the
history tables for wait events:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-ini"><div class="docs-select-all right" id="sa90036348"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-ini"><span class="token selector">[mysqld]</span>
<span class="token constant">performance_schema</span>
<span class="token constant">performance_schema_events_waits_history_size</span><span class="token attr-value"><span class="token punctuation">=</span>20</span>
<span class="token constant">performance_schema_events_waits_history_long_size</span><span class="token attr-value"><span class="token punctuation">=</span>15000</span></code></pre>
</div>
<p>
The Performance Schema automatically sizes the values of several
of its parameters at server startup if they are not set
explicitly. For example, it sizes the parameters that control the
sizes of the events waits tables this way. The Performance Schema
allocates memory incrementally, scaling its memory use to actual
server load, instead of allocating all the memory it needs during
server startup. Consequently, many sizing parameters need not be
set at all. To see which parameters are autosized or autoscaled,
use
<a class="link" href="mysqld.html" title="6.3.1 mysqld — The MySQL Server">
<span class="command">
<strong>
mysqld --verbose --help
</strong>
</span>
</a>
and examine the
option descriptions, or see
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
.
</p>
<p>
For each autosized parameter that is not set at server startup,
the Performance Schema determines how to set its value based on
the value of the following system values, which are considered as
<span class="quote">
“
<span class="quote">
hints
</span>
”
</span>
about how you have configured your MySQL
server:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-none"><div class="docs-select-all right" id="sa49958502"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-none">max_connections
open_files_limit
table_definition_cache
table_open_cache</code></pre>
</div>
<p>
To override autosizing or autoscaling for a given parameter, set
it to a value other than −1 at startup. In this case, the
Performance Schema assigns it the specified value.
</p>
<p>
At runtime,
<a class="link" href="show-variables.html" title="15.7.7.41 SHOW VARIABLES Statement">
<code class="literal">
SHOW VARIABLES
</code>
</a>
displays
the actual values that autosized parameters were set to.
Autoscaled parameters display with a value of −1.
</p>
<p>
If the Performance Schema is disabled, its autosized and
autoscaled parameters remain set to −1 and
<a class="link" href="show-variables.html" title="15.7.7.41 SHOW VARIABLES Statement">
<code class="literal">
SHOW VARIABLES
</code>
</a>
displays −1.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-replication-group-member-actions-table.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="performance-schema-replication-group-member-actions-table">
</a>
29.12.11.14 The replication_group_member_actions Table
</h4>
</div>
</div>
</div>
<a class="indexterm" name="idm46045070779968">
</a>
<a class="indexterm" name="idm46045070778464">
</a>
<p>
This table lists the member actions that are included in the
member actions configuration for replication group members.
The table is available only when Group Replication is
installed. You can reset the member actions configuration
using the
<a class="link" href="group-replication-functions-for-member-actions.html#function_group-replication-reset-member-actions">
<code class="literal">
group_replication_reset_member_actions()
</code>
</a>
function. For more information, see
<a class="xref" href="group-replication-member-actions.html" title="20.5.1.5 Configuring Member Actions">
Section 20.5.1.5, “Configuring Member Actions”
</a>
.
</p>
<p>
The
<code class="literal">
replication_group_member_actions
</code>
table
has these columns:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<code class="literal">
NAME
</code>
</p>
<p>
The name of the member action.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
EVENT
</code>
</p>
<p>
The event that triggers the member action.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
ENABLED
</code>
</p>
<p>
Whether the member action is currently enabled. Member
actions can be enabled using the
<a class="link" href="group-replication-functions-for-member-actions.html#function_group-replication-enable-member-action">
<code class="literal">
group_replication_enable_member_action()
</code>
</a>
function and disabled using the
<a class="link" href="group-replication-functions-for-member-actions.html#function_group-replication-disable-member-action">
<code class="literal">
group_replication_disable_member_action()
</code>
</a>
function.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
TYPE
</code>
</p>
<p>
The type of member action.
<code class="literal">
INTERNAL
</code>
is
an action that is provided by the Group Replication
plugin.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
PRIORITY
</code>
</p>
<p>
The priority of the member action. Actions with lower
priority values are actioned first.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
ERROR_HANDLING
</code>
</p>
<p>
The action that Group Replication takes if an error occurs
when the member action is being carried out.
<code class="literal">
IGNORE
</code>
means that an error message is
logged to say that the member action failed, but no
further action is taken.
<code class="literal">
CRITICAL
</code>
means
that the member moves into
<code class="literal">
ERROR
</code>
state,
and takes the action specified by the
<a class="link" href="group-replication-system-variables.html#sysvar_group_replication_exit_state_action">
<code class="literal">
group_replication_exit_state_action
</code>
</a>
system variable.
</p>
</li>
</ul>
</div>
<p>
The
<code class="literal">
replication_group_member_actions
</code>
table
has no indexes.
</p>
<p>
<a class="link" href="truncate-table.html" title="15.1.37 TRUNCATE TABLE Statement">
<code class="literal">
TRUNCATE TABLE
</code>
</a>
is not permitted
for the
<code class="literal">
replication_group_member_actions
</code>
table.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/setting-environment-variables.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="setting-environment-variables">
</a>
6.2.9 Setting Environment Variables
</h3>
</div>
</div>
</div>
<a class="indexterm" name="idm46045322053184">
</a>
<p>
Environment variables can be set at the command prompt to affect
the current invocation of your command processor, or set
permanently to affect future invocations. To set a variable
permanently, you can set it in a startup file or by using the
interface provided by your system for this purpose. Consult the
documentation for your command interpreter for specific details.
<a class="xref" href="environment-variables.html" title="6.9 Environment Variables">
Section 6.9, “Environment Variables”
</a>
, lists all environment
variables that affect MySQL program operation.
</p>
<p>
To specify a value for an environment variable, use the syntax
appropriate for your command processor. For example, on Windows,
you can set the
<code class="literal">
USER
</code>
variable to specify your
MySQL account name. To do so, use this syntax:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-terminal"><div class="docs-select-all right" id="sa28193208"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal">SET USER<span class="token attr-value"><span class="token punctuation">=</span><em class="replaceable">your_name</em></span></code></pre>
</div>
<p>
The syntax on Unix depends on your shell. Suppose that you want to
specify the TCP/IP port number using the
<code class="literal">
MYSQL_TCP_PORT
</code>
variable. Typical syntax (such
as for
<span class="command">
<strong>
sh
</strong>
</span>
,
<span class="command">
<strong>
ksh
</strong>
</span>
,
<span class="command">
<strong>
bash
</strong>
</span>
,
<span class="command">
<strong>
zsh
</strong>
</span>
, and so on) is as
follows:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-terminal"><div class="docs-select-all right" id="sa86594534"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal">MYSQL_TCP_PORT<span class="token attr-value"><span class="token punctuation">=</span>3306</span>
export MYSQL_TCP_PORT</code></pre>
</div>
<p>
The first command sets the variable, and the
<code class="literal">
export
</code>
command exports the variable to the
shell environment so that its value becomes accessible to MySQL
and other processes.
</p>
<p>
For
<span class="command">
<strong>
csh
</strong>
</span>
and
<span class="command">
<strong>
tcsh
</strong>
</span>
, use
<span class="command">
<strong>
setenv
</strong>
</span>
to make the shell variable available to
the environment:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-terminal"><div class="docs-select-all right" id="sa45821678"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal">setenv MYSQL_TCP_PORT 3306</code></pre>
</div>
<p>
The commands to set environment variables can be executed at your
command prompt to take effect immediately, but the settings
persist only until you log out. To have the settings take effect
each time you log in, use the interface provided by your system or
place the appropriate command or commands in a startup file that
your command interpreter reads each time it starts.
</p>
<p>
On Windows, you can set environment variables using the System
Control Panel (under Advanced).
</p>
<p>
On Unix, typical shell startup files are
<code class="filename">
.bashrc
</code>
or
<code class="filename">
.bash_profile
</code>
for
<span class="command">
<strong>
bash
</strong>
</span>
, or
<code class="filename">
.tcshrc
</code>
for
<span class="command">
<strong>
tcsh
</strong>
</span>
.
</p>
<p>
Suppose that your MySQL programs are installed in
<code class="literal">
/usr/local/mysql/bin
</code>
and that you want to make
it easy to invoke these programs. To do this, set the value of the
<code class="literal">
PATH
</code>
environment variable to include that
directory. For example, if your shell is
<span class="command">
<strong>
bash
</strong>
</span>
,
add the following line to your
<code class="filename">
.bashrc
</code>
file:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-terminal"><div class="docs-select-all right" id="sa8432243"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal">PATH<span class="token attr-value"><span class="token punctuation">=</span>${PATH}:/usr/local/mysql/bin</span></code></pre>
</div>
<p>
<span class="command">
<strong>
bash
</strong>
</span>
uses different startup files for login and
nonlogin shells, so you might want to add the setting to
<code class="filename">
.bashrc
</code>
for login shells and to
<code class="filename">
.bash_profile
</code>
for nonlogin shells to make
sure that
<code class="literal">
PATH
</code>
is set regardless.
</p>
<p>
If your shell is
<span class="command">
<strong>
tcsh
</strong>
</span>
, add the following line
to your
<code class="filename">
.tcshrc
</code>
file:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-terminal"><div class="docs-select-all right" id="sa33997896"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal">setenv PATH $<span class="token punctuation">{</span>PATH<span class="token punctuation">}</span><span class="token punctuation">:</span>/usr/local/mysql/bin</code></pre>
</div>
<p>
If the appropriate startup file does not exist in your home
directory, create it with a text editor.
</p>
<p>
After modifying your
<code class="literal">
PATH
</code>
setting, open a new
console window on Windows or log in again on Unix so that the
setting goes into effect.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/charset-server.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="charset-server">
</a>
12.3.2 Server Character Set and Collation
</h3>
</div>
</div>
</div>
<p>
MySQL Server has a server character set and a server collation.
By default, these are
<code class="literal">
utf8mb4
</code>
and
<code class="literal">
utf8mb4_0900_ai_ci
</code>
, but they can be set
explicitly at server startup on the command line or in an option
file and changed at runtime.
</p>
<p>
Initially, the server character set and collation depend on the
options that you use when you start
<a class="link" href="mysqld.html" title="6.3.1 mysqld — The MySQL Server">
<span class="command">
<strong>
mysqld
</strong>
</span>
</a>
.
You can use
<a class="link" href="server-system-variables.html#sysvar_character_set_server">
<code class="option">
--character-set-server
</code>
</a>
for the
character set. Along with it, you can add
<a class="link" href="server-system-variables.html#sysvar_collation_server">
<code class="option">
--collation-server
</code>
</a>
for the
collation. If you don't specify a character set, that is the
same as saying
<a class="link" href="server-system-variables.html#sysvar_character_set_server">
<code class="option">
--character-set-server=utf8mb4
</code>
</a>
.
If you specify only a character set (for example,
<code class="literal">
utf8mb4
</code>
) but not a collation, that is the
same as saying
<a class="link" href="server-system-variables.html#sysvar_character_set_server">
<code class="option">
--character-set-server=utf8mb4
</code>
</a>
<a class="link" href="server-system-variables.html#sysvar_collation_server">
<code class="option">
--collation-server=utf8mb4_0900_ai_ci
</code>
</a>
because
<code class="literal">
utf8mb4_0900_ai_ci
</code>
is the default
collation for
<code class="literal">
utf8mb4
</code>
. Therefore, the
following three commands all have the same effect:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-terminal"><div class="docs-select-all right" id="sa34821747"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal">mysqld
mysqld <span class="token constant">--character-set-server</span><span class="token attr-value"><span class="token punctuation">=</span>utf8mb4</span>
mysqld <span class="token constant">--character-set-server</span><span class="token attr-value"><span class="token punctuation">=</span>utf8mb4</span> \
<span class="token constant">--collation-server</span><span class="token attr-value"><span class="token punctuation">=</span>utf8mb4_0900_ai_ci</span></code></pre>
</div>
<p>
One way to change the settings is by recompiling. To change the
default server character set and collation when building from
sources, use the
<a class="link" href="source-configuration-options.html#option_cmake_default_charset">
<code class="option">
DEFAULT_CHARSET
</code>
</a>
and
<a class="link" href="source-configuration-options.html#option_cmake_default_collation">
<code class="option">
DEFAULT_COLLATION
</code>
</a>
options for
<span class="command">
<strong>
CMake
</strong>
</span>
. For example:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-terminal"><div class="docs-select-all right" id="sa32126305"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal">cmake <span class="token punctuation">.</span> <span class="token constant">-DDEFAULT_CHARSET</span><span class="token attr-value"><span class="token punctuation">=</span>latin1</span></code></pre>
</div>
<p>
Or:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-terminal"><div class="docs-select-all right" id="sa4612065"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal">cmake <span class="token punctuation">.</span> <span class="token constant">-DDEFAULT_CHARSET</span><span class="token attr-value"><span class="token punctuation">=</span>latin1</span> \
<span class="token constant">-DDEFAULT_COLLATION</span><span class="token attr-value"><span class="token punctuation">=</span>latin1_german1_ci</span></code></pre>
</div>
<p>
Both
<a class="link" href="mysqld.html" title="6.3.1 mysqld — The MySQL Server">
<span class="command">
<strong>
mysqld
</strong>
</span>
</a>
and
<span class="command">
<strong>
CMake
</strong>
</span>
verify that the character set/collation combination is valid. If
not, each program displays an error message and terminates.
</p>
<p>
The server character set and collation are used as default
values if the database character set and collation are not
specified in
<a class="link" href="create-database.html" title="15.1.12 CREATE DATABASE Statement">
<code class="literal">
CREATE DATABASE
</code>
</a>
statements. They have no other purpose.
</p>
<p>
The current server character set and collation can be determined
from the values of the
<a class="link" href="server-system-variables.html#sysvar_character_set_server">
<code class="literal">
character_set_server
</code>
</a>
and
<a class="link" href="server-system-variables.html#sysvar_collation_server">
<code class="literal">
collation_server
</code>
</a>
system
variables. These variables can be changed at runtime.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/system-variables-controlling-tracing.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="system-variables-controlling-tracing">
</a>
10.15.2 System Variables Controlling Tracing
</h3>
</div>
</div>
</div>
<p>
The following system variables affect optimizer tracing:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<a class="link" href="server-system-variables.html#sysvar_optimizer_trace">
<code class="literal">
optimizer_trace
</code>
</a>
: Enables or
disables optimizer tracing. See
<a class="xref" href="optimizer-trace-system-variable.html" title="10.15.8 The optimizer_trace System Variable">
Section 10.15.8, “The optimizer_trace System Variable”
</a>
.
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="server-system-variables.html#sysvar_optimizer_trace_features">
<code class="literal">
optimizer_trace_features
</code>
</a>
:
Enables or disables selected features of the MySQL Optimizer,
using the syntax shown here:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa91524731"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">SET</span> optimizer_trace_features<span class="token operator">=</span><span class="token keyword"><em class="replaceable">option</em></span><span class="token operator">=</span><span class="token keyword"><em class="replaceable">value</em></span><span class="token punctuation">[</span><span class="token punctuation">,</span><span class="token keyword"><em class="replaceable">option</em></span><span class="token operator">=</span><span class="token keyword"><em class="replaceable">value</em></span><span class="token punctuation">]</span><span class="token punctuation">[</span><span class="token punctuation">,</span><span class="token punctuation">.</span><span class="token punctuation">.</span><span class="token punctuation">.</span><span class="token punctuation">]</span>
<span class="token keyword"><em class="replaceable">option</em></span>:
{greedy_search <span class="token operator">|</span> range_optimizer <span class="token operator">|</span> dynamic_range <span class="token operator">|</span> repeated_subselect}
<span class="token keyword"><em class="replaceable">value</em></span>:
{<span class="token keyword">on</span> <span class="token operator">|</span> <span class="token keyword">off</span> <span class="token operator">|</span> <span class="token keyword">default</span>}</code></pre>
</div>
<p>
See
<a class="xref" href="optimizer-features-to-trace.html" title="10.15.10 Selecting Optimizer Features to Trace">
Section 10.15.10, “Selecting Optimizer Features to Trace”
</a>
, for more
information on the effects of these.
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="server-system-variables.html#sysvar_optimizer_trace_max_mem_size">
<code class="literal">
optimizer_trace_max_mem_size
</code>
</a>
:
Maximum amount of memory that can be used for storing all
traces.
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="server-system-variables.html#sysvar_optimizer_trace_limit">
<code class="literal">
optimizer_trace_limit
</code>
</a>
: The
maximum number of optimizer traces to be shown. See
<a class="xref" href="tuning-trace-purging.html" title="10.15.4 Tuning Trace Purging">
Section 10.15.4, “Tuning Trace Purging”
</a>
, for more information.
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="server-system-variables.html#sysvar_optimizer_trace_offset">
<code class="literal">
optimizer_trace_offset
</code>
</a>
:
Offset of the first trace shown. See
<a class="xref" href="tuning-trace-purging.html" title="10.15.4 Tuning Trace Purging">
Section 10.15.4, “Tuning Trace Purging”
</a>
.
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="server-system-variables.html#sysvar_end_markers_in_json">
<code class="literal">
end_markers_in_json
</code>
</a>
: If set
to
<code class="literal">
1
</code>
, causes the trace to repeat the key
(if present) near the closing bracket. This also affects the
output of
<a class="link" href="explain.html#explain-execution-plan" title="Obtaining Execution Plan Information">
<code class="literal">
EXPLAIN
FORMAT=JSON
</code>
</a>
in those versions of MySQL which support
this statement. See
<a class="xref" href="end-markers-in-json-system-variable.html" title="10.15.9 The end_markers_in_json System Variable">
Section 10.15.9, “The end_markers_in_json System Variable”
</a>
.
</p>
</li>
</ul>
</div>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-ndb-sync-pending-objects-table.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="performance-schema-ndb-sync-pending-objects-table">
</a>
29.12.12.1 The ndb_sync_pending_objects Table
</h4>
</div>
</div>
</div>
<p>
This table provides information about
<a class="link" href="mysql-cluster.html" title="Chapter 25 MySQL NDB Cluster 8.4">
<code class="literal">
NDB
</code>
</a>
database objects for which
mismatches have been detected and which are waiting to be
synchronized between the
<a class="link" href="mysql-cluster.html" title="Chapter 25 MySQL NDB Cluster 8.4">
<code class="literal">
NDB
</code>
</a>
dictionary and the MySQL data dictionary.
</p>
<p>
Example information about
<a class="link" href="mysql-cluster.html" title="Chapter 25 MySQL NDB Cluster 8.4">
<code class="literal">
NDB
</code>
</a>
database objects awaiting synchronization:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa74082655"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token operator">*</span> <span class="token keyword">FROM</span> performance_schema<span class="token punctuation">.</span>ndb_sync_pending_objects<span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> SCHEMA_NAME <span class="token punctuation">|</span> NAME <span class="token punctuation">|</span> TYPE <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> NULL <span class="token punctuation">|</span> lg1 <span class="token punctuation">|</span> LOGFILE GROUP <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> NULL <span class="token punctuation">|</span> ts1 <span class="token punctuation">|</span> TABLESPACE <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> db1 <span class="token punctuation">|</span> NULL <span class="token punctuation">|</span> SCHEMA <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> test <span class="token punctuation">|</span> t1 <span class="token punctuation">|</span> TABLE <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> test <span class="token punctuation">|</span> t2 <span class="token punctuation">|</span> TABLE <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> test <span class="token punctuation">|</span> t3 <span class="token punctuation">|</span> TABLE <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span></code></pre>
</div>
<p>
The
<a class="link" href="performance-schema-ndb-sync-pending-objects-table.html" title="29.12.12.1 The ndb_sync_pending_objects Table">
<code class="literal">
ndb_sync_pending_objects
</code>
</a>
table has these columns:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<code class="literal">
SCHEMA_NAME
</code>
: The name of the schema
(database) in which the object awaiting synchronization
resides; this is
<code class="literal">
NULL
</code>
for tablespaces
and log file groups
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
NAME
</code>
: The name of the object awaiting
synchronization; this is
<code class="literal">
NULL
</code>
if the
object is a schema
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
TYPE
</code>
: The type of the object awaiting
synchronization; this is one of
<code class="literal">
LOGFILE
GROUP
</code>
,
<code class="literal">
TABLESPACE
</code>
,
<code class="literal">
SCHEMA
</code>
, or
<code class="literal">
TABLE
</code>
</p>
</li>
</ul>
</div>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/information-schema-innodb-indexes-table.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="information-schema-innodb-indexes-table">
</a>
28.4.20 The INFORMATION_SCHEMA INNODB_INDEXES Table
</h3>
</div>
</div>
</div>
<a class="indexterm" name="idm46045076683488">
</a>
<p>
The
<a class="link" href="information-schema-innodb-indexes-table.html" title="28.4.20 The INFORMATION_SCHEMA INNODB_INDEXES Table">
<code class="literal">
INNODB_INDEXES
</code>
</a>
table provides
metadata about
<code class="literal">
InnoDB
</code>
indexes.
</p>
<p>
For related usage information and examples, see
<a class="xref" href="innodb-information-schema-system-tables.html" title="17.15.3 InnoDB INFORMATION_SCHEMA Schema Object Tables">
Section 17.15.3, “InnoDB INFORMATION_SCHEMA Schema Object Tables”
</a>
.
</p>
<p>
The
<a class="link" href="information-schema-innodb-indexes-table.html" title="28.4.20 The INFORMATION_SCHEMA INNODB_INDEXES Table">
<code class="literal">
INNODB_INDEXES
</code>
</a>
table has these
columns:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<code class="literal">
INDEX_ID
</code>
</p>
<p>
An identifier for the index. Index identifiers are unique
across all the databases in an instance.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
NAME
</code>
</p>
<p>
The name of the index. Most indexes created implicitly by
<code class="literal">
InnoDB
</code>
have consistent names but the index
names are not necessarily unique. Examples:
<code class="literal">
PRIMARY
</code>
for a primary key index,
<code class="literal">
GEN_CLUST_INDEX
</code>
for the index representing
a primary key when one is not specified, and
<code class="literal">
ID_IND
</code>
,
<code class="literal">
FOR_IND
</code>
, and
<code class="literal">
REF_IND
</code>
for foreign key constraints.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
TABLE_ID
</code>
</p>
<p>
An identifier representing the table associated with the
index; the same value as
<code class="literal">
INNODB_TABLES.TABLE_ID
</code>
.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
TYPE
</code>
</p>
<p>
A numeric value derived from bit-level information that
identifies the index type. 0 = nonunique secondary index; 1 =
automatically generated clustered index
(
<code class="literal">
GEN_CLUST_INDEX
</code>
); 2 = unique nonclustered
index; 3 = clustered index; 32 = full-text index; 64 = spatial
index; 128 = secondary index on a
<a class="link" href="glossary.html#glos_virtual_generated_column" title="virtual generated column">
virtual
generated column
</a>
.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
N_FIELDS
</code>
</p>
<p>
The number of columns in the index key. For
<code class="literal">
GEN_CLUST_INDEX
</code>
indexes, this value is 0
because the index is created using an artificial value rather
than a real table column.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
PAGE_NO
</code>
</p>
<p>
The root page number of the index B-tree. For full-text
indexes, the
<code class="literal">
PAGE_NO
</code>
column is unused and
set to -1 (
<code class="literal">
FIL_NULL
</code>
) because the full-text
index is laid out in several B-trees (auxiliary tables).
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
SPACE
</code>
</p>
<p>
An identifier for the tablespace where the index resides. 0
means the
<code class="literal">
InnoDB
</code>
<a class="link" href="glossary.html#glos_system_tablespace" title="system tablespace">
system
tablespace
</a>
. Any other number represents a table created
with a separate
<code class="literal">
.ibd
</code>
file in
<a class="link" href="glossary.html#glos_file_per_table" title="file-per-table">
file-per-table
</a>
mode. This identifier stays the same after a
<a class="link" href="truncate-table.html" title="15.1.37 TRUNCATE TABLE Statement">
<code class="literal">
TRUNCATE TABLE
</code>
</a>
statement.
Because all indexes for a table reside in the same tablespace
as the table, this value is not necessarily unique.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
MERGE_THRESHOLD
</code>
</p>
<p>
The merge threshold value for index pages. If the amount of
data in an index page falls below the
<a class="link" href="index-page-merge-threshold.html" title="17.8.11 Configuring the Merge Threshold for Index Pages">
<code class="literal">
MERGE_THRESHOLD
</code>
</a>
value when a row is deleted or when a row is shortened by an
update operation,
<code class="literal">
InnoDB
</code>
attempts to merge
the index page with the neighboring index page. The default
threshold value is 50%. For more information, see
<a class="xref" href="index-page-merge-threshold.html" title="17.8.11 Configuring the Merge Threshold for Index Pages">
Section 17.8.11, “Configuring the Merge Threshold for Index Pages”
</a>
.
</p>
</li>
</ul>
</div>
<h4>
<a name="idm46045076643728">
</a>
Example
</h4>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa45937518"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token operator">*</span> <span class="token keyword">FROM</span> INFORMATION_SCHEMA<span class="token punctuation">.</span>INNODB_INDEXES <span class="token keyword">WHERE</span> TABLE_ID <span class="token operator">=</span> <span class="token number">34</span>\G
<span class="token output"><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span> 1. row <span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span>
INDEX_ID<span class="token punctuation">:</span> 39
NAME<span class="token punctuation">:</span> GEN_CLUST_INDEX
TABLE_ID<span class="token punctuation">:</span> 34
TYPE<span class="token punctuation">:</span> 1
N_FIELDS<span class="token punctuation">:</span> 0
PAGE_NO<span class="token punctuation">:</span> 3
SPACE<span class="token punctuation">:</span> 23
MERGE_THRESHOLD<span class="token punctuation">:</span> 50
<span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span> 2. row <span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span>
INDEX_ID<span class="token punctuation">:</span> 40
NAME<span class="token punctuation">:</span> i1
TABLE_ID<span class="token punctuation">:</span> 34
TYPE<span class="token punctuation">:</span> 0
N_FIELDS<span class="token punctuation">:</span> 1
PAGE_NO<span class="token punctuation">:</span> 4
SPACE<span class="token punctuation">:</span> 23
MERGE_THRESHOLD<span class="token punctuation">:</span> 50</span></code></pre>
</div>
<h4>
<a name="idm46045076640912">
</a>
Notes
</h4>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
You must have the
<a class="link" href="privileges-provided.html#priv_process">
<code class="literal">
PROCESS
</code>
</a>
privilege to query this table.
</p>
</li>
<li class="listitem">
<p>
Use the
<code class="literal">
INFORMATION_SCHEMA
</code>
<a class="link" href="information-schema-columns-table.html" title="28.3.8 The INFORMATION_SCHEMA COLUMNS Table">
<code class="literal">
COLUMNS
</code>
</a>
table or the
<a class="link" href="show-columns.html" title="15.7.7.6 SHOW COLUMNS Statement">
<code class="literal">
SHOW COLUMNS
</code>
</a>
statement to view
additional information about the columns of this table,
including data types and default values.
</p>
</li>
</ul>
</div>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/dynamic-format.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="dynamic-format">
</a>
18.2.3.2 Dynamic Table Characteristics
</h4>
</div>
</div>
</div>
<a class="indexterm" name="idm46045148084848">
</a>
<a class="indexterm" name="idm46045148083792">
</a>
<p>
Dynamic storage format is used if a
<code class="literal">
MyISAM
</code>
table contains any variable-length columns
(
<a class="link" href="char.html" title="13.3.2 The CHAR and VARCHAR Types">
<code class="literal">
VARCHAR
</code>
</a>
,
<a class="link" href="binary-varbinary.html" title="13.3.3 The BINARY and VARBINARY Types">
<code class="literal">
VARBINARY
</code>
</a>
,
<a class="link" href="blob.html" title="13.3.4 The BLOB and TEXT Types">
<code class="literal">
BLOB
</code>
</a>
, or
<a class="link" href="blob.html" title="13.3.4 The BLOB and TEXT Types">
<code class="literal">
TEXT
</code>
</a>
), or if the table was
created with the
<code class="literal">
ROW_FORMAT=DYNAMIC
</code>
table
option.
</p>
<p>
Dynamic format is a little more complex than static format
because each row has a header that indicates how long it is. A
row can become fragmented (stored in noncontiguous pieces) when
it is made longer as a result of an update.
</p>
<a class="indexterm" name="idm46045148074720">
</a>
<p>
You can use
<a class="link" href="optimize-table.html" title="15.7.3.4 OPTIMIZE TABLE Statement">
<code class="literal">
OPTIMIZE TABLE
</code>
</a>
or
<a class="link" href="myisamchk.html" title="6.6.4 myisamchk — MyISAM Table-Maintenance Utility">
<span class="command">
<strong>
myisamchk -r
</strong>
</span>
</a>
to defragment a table. If you
have fixed-length columns that you access or change frequently
in a table that also contains some variable-length columns, it
might be a good idea to move the variable-length columns to
other tables just to avoid fragmentation.
</p>
<p>
Dynamic-format tables have these characteristics:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
All string columns are dynamic except those with a length
less than four.
</p>
</li>
<li class="listitem">
<p>
Each row is preceded by a bitmap that indicates which
columns contain the empty string (for string columns) or
zero (for numeric columns). This does not include columns
that contain
<code class="literal">
NULL
</code>
values. If a string
column has a length of zero after trailing space removal, or
a numeric column has a value of zero, it is marked in the
bitmap and not saved to disk. Nonempty strings are saved as
a length byte plus the string contents.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
NULL
</code>
columns require additional space in
the row to record whether their values are
<code class="literal">
NULL
</code>
. Each
<code class="literal">
NULL
</code>
column
takes one bit extra, rounded up to the nearest byte.
</p>
</li>
<li class="listitem">
<p>
Much less disk space usually is required than for
fixed-length tables.
</p>
</li>
<li class="listitem">
<p>
Each row uses only as much space as is required. However, if
a row becomes larger, it is split into as many pieces as are
required, resulting in row fragmentation. For example, if
you update a row with information that extends the row
length, the row becomes fragmented. In this case, you may
have to run
<a class="link" href="optimize-table.html" title="15.7.3.4 OPTIMIZE TABLE Statement">
<code class="literal">
OPTIMIZE TABLE
</code>
</a>
or
<a class="link" href="myisamchk.html" title="6.6.4 myisamchk — MyISAM Table-Maintenance Utility">
<span class="command">
<strong>
myisamchk -r
</strong>
</span>
</a>
from time to time to improve
performance. Use
<a class="link" href="myisamchk.html" title="6.6.4 myisamchk — MyISAM Table-Maintenance Utility">
<span class="command">
<strong>
myisamchk -ei
</strong>
</span>
</a>
to obtain
table statistics.
</p>
</li>
<li class="listitem">
<p>
More difficult than static-format tables to reconstruct
after a crash, because rows may be fragmented into many
pieces and links (fragments) may be missing.
</p>
</li>
<li class="listitem">
<p>
The expected row length for dynamic-sized rows is calculated
using the following expression:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-none"><div class="docs-select-all right" id="sa18683237"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-none">3
+ (<em class="replaceable">number of columns</em> + 7) / 8
+ (<em class="replaceable">number of char columns</em>)
+ (<em class="replaceable">packed size of numeric columns</em>)
+ (<em class="replaceable">length of strings</em>)
+ (<em class="replaceable">number of NULL columns</em> + 7) / 8</code></pre>
</div>
<p>
There is a penalty of 6 bytes for each link. A dynamic row
is linked whenever an update causes an enlargement of the
row. Each new link is at least 20 bytes, so the next
enlargement probably goes in the same link. If not, another
link is created. You can find the number of links using
<a class="link" href="myisamchk.html" title="6.6.4 myisamchk — MyISAM Table-Maintenance Utility">
<span class="command">
<strong>
myisamchk -ed
</strong>
</span>
</a>
. All links may be removed
with
<a class="link" href="optimize-table.html" title="15.7.3.4 OPTIMIZE TABLE Statement">
<code class="literal">
OPTIMIZE TABLE
</code>
</a>
or
<a class="link" href="myisamchk.html" title="6.6.4 myisamchk — MyISAM Table-Maintenance Utility">
<span class="command">
<strong>
myisamchk -r
</strong>
</span>
</a>
.
</p>
</li>
</ul>
</div>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/creating-ssl-rsa-files-using-mysql.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="creating-ssl-rsa-files-using-mysql">
</a>
8.3.3.1 Creating SSL and RSA Certificates and Keys using MySQL
</h4>
</div>
</div>
</div>
<p>
MySQL provides these ways to create the SSL certificate and key
files and RSA key-pair files required to support encrypted
connections using SSL and secure password exchange using RSA
over unencrypted connections, if those files are missing:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
The server can autogenerate these files at startup, for
MySQL distributions.
</p>
</li>
</ul>
</div>
<div class="important" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Important
</div>
<p>
Server autogeneration helps lower the barrier to using SSL by
making it easier to generate the required files. However,
certificates generated by this method are self-signed, which
may not be very secure. After you gain experience using these,
consider obtaining certificate and key material from a
registered certificate authority.
</p>
</div>
<div class="important" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Important
</div>
<p>
If a client connecting to a MySQL server instance uses an SSL
certificate with the
<code class="literal">
extendedKeyUsage
</code>
extension (an X.509 v3 extension), the extended key usage must
include client authentication (
<code class="literal">
clientAuth
</code>
).
If the SSL certificate is only specified for server
authentication (
<code class="literal">
serverAuth
</code>
) and other
non-client certificate purposes, certificate verification
fails and the client connection to the MySQL server instance
fails. There is no
<code class="literal">
extendedKeyUsage
</code>
extension in SSL certificates generated by MySQL Server. If
you use your own client certificate created in another way,
ensure any
<code class="literal">
extendedKeyUsage
</code>
extension
includes client authentication.
</p>
</div>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<a class="xref" href="creating-ssl-rsa-files-using-mysql.html#creating-ssl-rsa-files-using-mysql-automatic" title="Automatic SSL and RSA File Generation">
Automatic SSL and RSA File Generation
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="xref" href="creating-ssl-rsa-files-using-mysql.html#creating-ssl-rsa-files-using-mysql-ssl-and-rsa-file-characteristics" title="SSL and RSA File Characteristics">
SSL and RSA File Characteristics
</a>
</p>
</li>
</ul>
</div>
<div class="simplesect">
<div class="titlepage">
<div>
<div class="simple">
<h5 class="title">
<a name="creating-ssl-rsa-files-using-mysql-automatic">
</a>
Automatic SSL and RSA File Generation
</h5>
</div>
</div>
</div>
<p>
For MySQL distributions compiled using OpenSSL, the MySQL
server has the capability of automatically generating missing
SSL and RSA files at startup. The
<a class="link" href="server-system-variables.html#sysvar_auto_generate_certs">
<code class="literal">
auto_generate_certs
</code>
</a>
,
<a class="link" href="server-system-variables.html#sysvar_sha256_password_auto_generate_rsa_keys">
<code class="literal">
sha256_password_auto_generate_rsa_keys
</code>
</a>
,
and
<a class="link" href="server-system-variables.html#sysvar_caching_sha2_password_auto_generate_rsa_keys">
<code class="literal">
caching_sha2_password_auto_generate_rsa_keys
</code>
</a>
system variables control automatic generation of these files.
These variables are enabled by default. They can be enabled at
startup and inspected but not set at runtime.
</p>
<p>
At startup, the server automatically generates server-side and
client-side SSL certificate and key files in the data
directory if the
<a class="link" href="server-system-variables.html#sysvar_auto_generate_certs">
<code class="literal">
auto_generate_certs
</code>
</a>
system
variable is enabled, no SSL options are specified, and the
server-side SSL files are missing from the data directory.
These files enable encrypted client connections using SSL; see
<a class="xref" href="using-encrypted-connections.html" title="8.3.1 Configuring MySQL to Use Encrypted Connections">
Section 8.3.1, “Configuring MySQL to Use Encrypted Connections”
</a>
.
</p>
<div class="orderedlist">
<ol class="orderedlist" type="1">
<li class="listitem">
<p>
The server checks the data directory for SSL files with
the following names:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-ini"><div class="docs-select-all right" id="sa94524176"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-ini">ca.pem
server-cert.pem
server-key.pem</code></pre>
</div>
</li>
<li class="listitem">
<p>
If any of those files are present, the server creates no
SSL files. Otherwise, it creates them, plus some
additional files:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-ini"><div class="docs-select-all right" id="sa98950606"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-ini">ca.pem Self-signed CA certificate
ca-key.pem CA private key
server-cert.pem Server certificate
server-key.pem Server private key
client-cert.pem Client certificate
client-key.pem Client private key</code></pre>
</div>
</li>
<li class="listitem">
<p>
If the server autogenerates SSL files, it uses the names
of the
<code class="filename">
ca.pem
</code>
,
<code class="filename">
server-cert.pem
</code>
, and
<code class="filename">
server-key.pem
</code>
files to set the
corresponding system variables
(
<a class="link" href="server-system-variables.html#sysvar_ssl_ca">
<code class="literal">
ssl_ca
</code>
</a>
,
<a class="link" href="server-system-variables.html#sysvar_ssl_cert">
<code class="literal">
ssl_cert
</code>
</a>
,
<a class="link" href="server-system-variables.html#sysvar_ssl_key">
<code class="literal">
ssl_key
</code>
</a>
).
</p>
</li>
</ol>
</div>
<p>
At startup, the server automatically generates RSA
private/public key-pair files in the data directory if all of
these conditions are true: The
<a class="link" href="server-system-variables.html#sysvar_sha256_password_auto_generate_rsa_keys">
<code class="literal">
sha256_password_auto_generate_rsa_keys
</code>
</a>
or
<a class="link" href="server-system-variables.html#sysvar_caching_sha2_password_auto_generate_rsa_keys">
<code class="literal">
caching_sha2_password_auto_generate_rsa_keys
</code>
</a>
system variable is enabled; no RSA options are specified; the
RSA files are missing from the data directory. These key-pair
files enable secure password exchange using RSA over
unencrypted connections for accounts authenticated by the
<code class="literal">
sha256_password
</code>
(deprecated) or
<code class="literal">
caching_sha2_password
</code>
plugin; see
<a class="xref" href="sha256-pluggable-authentication.html" title="8.4.1.3 SHA-256 Pluggable Authentication">
Section 8.4.1.3, “SHA-256 Pluggable Authentication”
</a>
, and
<a class="xref" href="caching-sha2-pluggable-authentication.html" title="8.4.1.2 Caching SHA-2 Pluggable Authentication">
Section 8.4.1.2, “Caching SHA-2 Pluggable Authentication”
</a>
.
</p>
<div class="orderedlist">
<ol class="orderedlist" type="1">
<li class="listitem">
<p>
The server checks the data directory for RSA files with
the following names:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-ini"><div class="docs-select-all right" id="sa1248432"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-ini">private_key.pem Private member of private/public key pair
public_key.pem Public member of private/public key pair</code></pre>
</div>
</li>
<li class="listitem">
<p>
If any of these files are present, the server creates no
RSA files. Otherwise, it creates them.
</p>
</li>
<li class="listitem">
<p>
If the server autogenerates the RSA files, it uses their
names to set the corresponding system variables
(
<a class="link" href="server-system-variables.html#sysvar_sha256_password_private_key_path">
<code class="literal">
sha256_password_private_key_path
</code>
</a>
and
<a class="link" href="server-system-variables.html#sysvar_sha256_password_public_key_path">
<code class="literal">
sha256_password_public_key_path
</code>
</a>
;
<a class="link" href="server-system-variables.html#sysvar_caching_sha2_password_private_key_path">
<code class="literal">
caching_sha2_password_private_key_path
</code>
</a>
and
<a class="link" href="server-system-variables.html#sysvar_caching_sha2_password_public_key_path">
<code class="literal">
caching_sha2_password_public_key_path
</code>
</a>
).
</p>
</li>
</ol>
</div>
</div>
<div class="simplesect">
<div class="titlepage">
<div>
<div class="simple">
<h5 class="title">
<a name="creating-ssl-rsa-files-using-mysql-ssl-and-rsa-file-characteristics">
</a>
SSL and RSA File Characteristics
</h5>
</div>
</div>
</div>
<p>
SSL and RSA files created automatically by the server have
these characteristics:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
SSL and RSA keys have a size of 2048 bits.
</p>
</li>
<li class="listitem">
<p>
The SSL CA certificate is self signed.
</p>
</li>
<li class="listitem">
<p>
The SSL server and client certificates are signed with the
CA certificate and key, using the
<code class="literal">
sha256WithRSAEncryption
</code>
signature
algorithm.
</p>
</li>
<li class="listitem">
<p>
SSL certificates use these Common Name (CN) values, with
the appropriate certificate type (CA, Server, Client):
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-ini"><div class="docs-select-all right" id="sa22795556"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-ini">ca.pem: MySQL_Server_<em class="replaceable">suffix</em>_Auto_Generated_CA_Certificate
server-cert.pm: MySQL_Server_<em class="replaceable">suffix</em>_Auto_Generated_Server_Certificate
client-cert.pm: MySQL_Server_<em class="replaceable">suffix</em>_Auto_Generated_Client_Certificate</code></pre>
</div>
<p>
The
<em class="replaceable">
<code>
suffix
</code>
</em>
value is based on
the MySQL version number.
</p>
<p>
For files generated by the server, if the resulting CN
values exceed 64 characters, the
<code class="literal">
_
<em class="replaceable">
<code>
suffix
</code>
</em>
</code>
portion of the name is omitted.
</p>
</li>
<li class="listitem">
<p>
SSL files have blank values for Country (C), State or
Province (ST), Organization (O), Organization Unit Name
(OU) and email address.
</p>
</li>
<li class="listitem">
<p>
SSL files created by the server are valid for ten years
from the time of generation.
</p>
</li>
<li class="listitem">
<p>
RSA files do not expire.
</p>
</li>
<li class="listitem">
<p>
SSL files have different serial numbers for each
certificate/key pair (1 for CA, 2 for Server, 3 for
Client).
</p>
</li>
<li class="listitem">
<p>
Files created automatically by the server are owned by the
account that runs the server.
</p>
</li>
<li class="listitem">
<p>
On Unix and Unix-like systems, the file access mode is 644
for certificate files (that is, world readable) and 600
for key files (that is, accessible only by the account
that runs the server).
</p>
</li>
</ul>
</div>
<p>
To see the contents of an SSL certificate (for example, to
check the range of dates over which it is valid), invoke
<span class="command">
<strong>
openssl
</strong>
</span>
directly:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-terminal"><div class="docs-select-all right" id="sa27926201"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal">openssl x509 <span class="token property">-text</span> <span class="token property">-in</span> ca<span class="token punctuation">.</span>pem
openssl x509 <span class="token property">-text</span> <span class="token property">-in</span> server-cert<span class="token punctuation">.</span>pem
openssl x509 <span class="token property">-text</span> <span class="token property">-in</span> client-cert<span class="token punctuation">.</span>pem</code></pre>
</div>
<p>
It is also possible to check SSL certificate expiration
information using this SQL statement:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa92944486"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SHOW</span> <span class="token keyword">STATUS</span> <span class="token operator">LIKE</span> <span class="token string">'Ssl_server_not%'</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> Variable_name <span class="token punctuation">|</span> Value <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> Ssl_server_not_after <span class="token punctuation">|</span> Apr 28 14:16:39 2027 GMT <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> Ssl_server_not_before <span class="token punctuation">|</span> May 1 14:16:39 2017 GMT <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span></code></pre>
</div>
</div>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/mysql-innodb-replicaset-introduction.html | <div id="docs-body">
<div class="chapter">
<div class="titlepage">
<div>
<div>
<h1 class="title">
<a name="mysql-innodb-replicaset-introduction">
</a>
Chapter 24 InnoDB ReplicaSet
</h1>
</div>
</div>
</div>
<a class="indexterm" name="idm46045124488768">
</a>
<p>
This chapter introduces MySQL InnoDB ReplicaSet, which combines
MySQL technologies to enable you to deploy and administer
<a class="xref" href="replication.html" title="Chapter 19 Replication">
Chapter 19,
<i>
Replication
</i>
</a>
. This content is a high-level overview
of InnoDB ReplicaSet, for full documentation, see
<a class="ulink" href="/doc/mysql-shell/8.4/en/mysql-innodb-replicaset.html" target="_top">
MySQL InnoDB ReplicaSet
</a>
.
</p>
<p>
An InnoDB ReplicaSet consists of at least two MySQL Server
instances, and it provides all of the MySQL Replication features you
are familiar with, such as read scale-out and data security.
InnoDB ReplicaSet uses the following MySQL technologies:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<a class="ulink" href="/doc/mysql-shell/8.4/en/" target="_top">
MySQL Shell
</a>
, which is an
advanced client and code editor for MySQL.
</p>
</li>
<li class="listitem">
<p>
MySQL Server, and
<a class="xref" href="replication.html" title="Chapter 19 Replication">
Chapter 19,
<i>
Replication
</i>
</a>
, which enables a
set of MySQL instances to provide availability and asynchronous
read scale-out. InnoDB ReplicaSet provides an alternative,
easy to use programmatic way to work with Replication.
</p>
</li>
<li class="listitem">
<p>
<a class="ulink" href="/doc/mysql-router/8.4/en/" target="_top">
MySQL Router
</a>
, a lightweight
middleware that provides transparent routing between your
application and InnoDB ReplicaSet.
</p>
</li>
</ul>
</div>
<p>
The interface to an InnoDB ReplicaSet is similar to
<a class="ulink" href="/doc/mysql-shell/8.4/en/mysql-innodb-cluster.html" target="_top">
MySQL InnoDB Cluster
</a>
, you use MySQL Shell to work
with MySQL Server instances as a ReplicaSet, and MySQL Router is also
tightly integrated in the same way as InnoDB Cluster.
</p>
<p>
Being based on MySQL Replication, an InnoDB ReplicaSet has a
single primary, which replicates to one or more secondary instances.
An InnoDB ReplicaSet does not provide all of the features which
InnoDB Cluster provides, such as automatic failover, or
multi-primary mode. But, it does support features such as
configuring, adding, and removing instances in a similar way. You
can manually switch over or fail over to a secondary instance, for
example in the event of a failure. You can even adopt an existing
Replication deployment and then administer it as an
InnoDB ReplicaSet.
</p>
<p>
You work with InnoDB ReplicaSet using the
<a class="ulink" href="/doc/mysql-shell/8.4/en/admin-api-overview.html" target="_top">
AdminAPI
</a>
, provided as
part of MySQL Shell. AdminAPI is available in JavaScript and
Python, and is well suited to scripting and automation of
deployments of MySQL to achieve high-availability and scalability.
By using MySQL Shell's AdminAPI, you can avoid the need to
configure many instances manually. Instead, AdminAPI provides an
effective modern interface to sets of MySQL instances and enables
you to provision, administer, and monitor your deployment from one
central tool.
</p>
<p>
To get started with InnoDB ReplicaSet you need to
<a class="ulink" href="https://dev.mysql.com/downloads/shell/" target="_top">
download
</a>
and
<a class="ulink" href="/doc/mysql-shell/8.4/en/mysql-shell-install.html" target="_top">
install
</a>
MySQL Shell.
You need some hosts with MySQL Server instances
<a class="link" href="installing.html" title="Chapter 2 Installing MySQL">
installed
</a>
, and you can also
<a class="ulink" href="/doc/mysql-router/8.4/en/mysql-router-installation.html" target="_top">
install
</a>
MySQL Router.
</p>
<p>
InnoDB ReplicaSet supports
<a class="link" href="clone-plugin.html" title="7.6.7 The Clone Plugin">
MySQL
Clone
</a>
, which enables you to provision instances simply. In
the past, to provision a new instance before it joined a MySQL
Replication deployment, you would need to somehow manually transfer
the transactions to the joining instance. This could involve making
file copies, manually copying them, and so on. You can simply
<a class="ulink" href="/doc/mysql-shell/8.4/en/add-instance-replicaset.html" target="_top">
add an instance
</a>
to
the replica set and it is automatically provisioned.
</p>
<p>
Similarly, InnoDB ReplicaSet is tightly integrated with
<a class="ulink" href="/doc/mysql-router/8.4/en/" target="_top">
MySQL Router
</a>
, and you can use
AdminAPI to
<a class="ulink" href="/doc/mysql-shell/8.4/en/registered-routers.html" target="_top">
work with
</a>
them together. MySQL Router can automatically configure itself based on
an InnoDB ReplicaSet, in a process called
<a class="ulink" href="/doc/mysql-shell/8.4/en/admin-api-bootstrapping-router.html" target="_top">
bootstrapping
</a>
,
which removes the need for you to configure routing manually.
MySQL Router then transparently connects client applications to the
InnoDB ReplicaSet, providing routing and load-balancing for client
connections. This integration also enables you to administer some
aspects of a MySQL Router bootstrapped against an InnoDB ReplicaSet
using AdminAPI. InnoDB ReplicaSet status information includes
details about MySQL Routers bootstrapped against the ReplicaSet.
Operations enable you to
<a class="ulink" href="/doc/mysql-shell/8.4/en/configuring-router-user.html" target="_top">
create MySQL Router users
</a>
at the ReplicaSet level, to work with the MySQL Routers bootstrapped
against the ReplicaSet, and so on.
</p>
<p>
For more information on these technologies, see the user
documentation linked in the descriptions. In addition to this user
documentation, there is developer documentation for all AdminAPI
methods in the MySQL Shell JavaScript API Reference or MySQL Shell
Python API Reference, available from
<a class="ulink" href="/doc/index-connectors.html" target="_top">
Connectors and APIs
</a>
.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-status-monitoring.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h2 class="title">
<a name="performance-schema-status-monitoring">
</a>
29.7 Performance Schema Status Monitoring
</h2>
</div>
</div>
</div>
<p>
There are several status variables associated with the Performance
Schema:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa56979624"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SHOW</span> <span class="token keyword">STATUS</span> <span class="token operator">LIKE</span> <span class="token string">'perf%'</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> Variable_name <span class="token punctuation">|</span> Value <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> Performance_schema_accounts_lost <span class="token punctuation">|</span> 0 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> Performance_schema_cond_classes_lost <span class="token punctuation">|</span> 0 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> Performance_schema_cond_instances_lost <span class="token punctuation">|</span> 0 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> Performance_schema_digest_lost <span class="token punctuation">|</span> 0 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> Performance_schema_file_classes_lost <span class="token punctuation">|</span> 0 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> Performance_schema_file_handles_lost <span class="token punctuation">|</span> 0 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> Performance_schema_file_instances_lost <span class="token punctuation">|</span> 0 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> Performance_schema_hosts_lost <span class="token punctuation">|</span> 0 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> Performance_schema_locker_lost <span class="token punctuation">|</span> 0 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> Performance_schema_memory_classes_lost <span class="token punctuation">|</span> 0 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> Performance_schema_metadata_lock_lost <span class="token punctuation">|</span> 0 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> Performance_schema_mutex_classes_lost <span class="token punctuation">|</span> 0 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> Performance_schema_mutex_instances_lost <span class="token punctuation">|</span> 0 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> Performance_schema_nested_statement_lost <span class="token punctuation">|</span> 0 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> Performance_schema_program_lost <span class="token punctuation">|</span> 0 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> Performance_schema_rwlock_classes_lost <span class="token punctuation">|</span> 0 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> Performance_schema_rwlock_instances_lost <span class="token punctuation">|</span> 0 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> Performance_schema_session_connect_attrs_lost <span class="token punctuation">|</span> 0 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> Performance_schema_socket_classes_lost <span class="token punctuation">|</span> 0 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> Performance_schema_socket_instances_lost <span class="token punctuation">|</span> 0 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> Performance_schema_stage_classes_lost <span class="token punctuation">|</span> 0 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> Performance_schema_statement_classes_lost <span class="token punctuation">|</span> 0 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> Performance_schema_table_handles_lost <span class="token punctuation">|</span> 0 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> Performance_schema_table_instances_lost <span class="token punctuation">|</span> 0 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> Performance_schema_thread_classes_lost <span class="token punctuation">|</span> 0 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> Performance_schema_thread_instances_lost <span class="token punctuation">|</span> 0 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> Performance_schema_users_lost <span class="token punctuation">|</span> 0 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span></code></pre>
</div>
<p>
The Performance Schema status variables provide information about
instrumentation that could not be loaded or created due to memory
constraints. Names for these variables have several forms:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<code class="literal">
Performance_schema_
<em class="replaceable">
<code>
xxx
</code>
</em>
_classes_lost
</code>
indicates how many instruments of type
<em class="replaceable">
<code>
xxx
</code>
</em>
could not be loaded.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Performance_schema_
<em class="replaceable">
<code>
xxx
</code>
</em>
_instances_lost
</code>
indicates how many instances of object type
<em class="replaceable">
<code>
xxx
</code>
</em>
could not be created.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Performance_schema_
<em class="replaceable">
<code>
xxx
</code>
</em>
_handles_lost
</code>
indicates how many instances of object type
<em class="replaceable">
<code>
xxx
</code>
</em>
could not be opened.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Performance_schema_locker_lost
</code>
indicates
how many events are
<span class="quote">
“
<span class="quote">
lost
</span>
”
</span>
or not recorded.
</p>
</li>
</ul>
</div>
<p>
For example, if a mutex is instrumented in the server source but
the server cannot allocate memory for the instrumentation at
runtime, it increments
<a class="link" href="performance-schema-status-variables.html#statvar_Performance_schema_mutex_classes_lost">
<code class="literal">
Performance_schema_mutex_classes_lost
</code>
</a>
.
The mutex still functions as a synchronization object (that is,
the server continues to function normally), but performance data
for it is not collected. If the instrument can be allocated, it
can be used for initializing instrumented mutex instances. For a
singleton mutex such as a global mutex, there is only one
instance. Other mutexes have an instance per connection, or per
page in various caches and data buffers, so the number of
instances varies over time. Increasing the maximum number of
connections or the maximum size of some buffers increases the
maximum number of instances that might be allocated at once. If
the server cannot create a given instrumented mutex instance, it
increments
<a class="link" href="performance-schema-status-variables.html#statvar_Performance_schema_mutex_instances_lost">
<code class="literal">
Performance_schema_mutex_instances_lost
</code>
</a>
.
</p>
<p>
Suppose that the following conditions hold:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
The server was started with the
<a class="link" href="performance-schema-system-variables.html#sysvar_performance_schema_max_mutex_classes">
<code class="option">
--performance_schema_max_mutex_classes=200
</code>
</a>
option and thus has room for 200 mutex instruments.
</p>
</li>
<li class="listitem">
<p>
150 mutex instruments have been loaded already.
</p>
</li>
<li class="listitem">
<p>
The plugin named
<code class="literal">
plugin_a
</code>
contains 40 mutex
instruments.
</p>
</li>
<li class="listitem">
<p>
The plugin named
<code class="literal">
plugin_b
</code>
contains 20 mutex
instruments.
</p>
</li>
</ul>
</div>
<p>
The server allocates mutex instruments for the plugins depending
on how many they need and how many are available, as illustrated
by the following sequence of statements:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-sql"><div class="docs-select-all right" id="sa30532506"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">INSTALL</span> <span class="token keyword">PLUGIN</span> plugin_a</code></pre>
</div>
<p>
The server now has 150+40 = 190 mutex instruments.
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-sql"><div class="docs-select-all right" id="sa10018656"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">UNINSTALL</span> <span class="token keyword">PLUGIN</span> plugin_a<span class="token punctuation">;</span></code></pre>
</div>
<p>
The server still has 190 instruments. All the historical data
generated by the plugin code is still available, but new events
for the instruments are not collected.
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-sql"><div class="docs-select-all right" id="sa76627941"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">INSTALL</span> <span class="token keyword">PLUGIN</span> plugin_a<span class="token punctuation">;</span></code></pre>
</div>
<p>
The server detects that the 40 instruments are already defined, so
no new instruments are created, and previously assigned internal
memory buffers are reused. The server still has 190 instruments.
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-sql"><div class="docs-select-all right" id="sa83092643"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">INSTALL</span> <span class="token keyword">PLUGIN</span> plugin_b<span class="token punctuation">;</span></code></pre>
</div>
<p>
The server has room for 200-190 = 10 instruments (in this case,
mutex classes), and sees that the plugin contains 20 new
instruments. 10 instruments are loaded, and 10 are discarded or
<span class="quote">
“
<span class="quote">
lost.
</span>
”
</span>
The
<a class="link" href="performance-schema-status-variables.html#statvar_Performance_schema_mutex_classes_lost">
<code class="literal">
Performance_schema_mutex_classes_lost
</code>
</a>
indicates the number of instruments (mutex classes) lost:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa28620951"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SHOW</span> <span class="token keyword">STATUS</span> <span class="token operator">LIKE</span> <span class="token string">"perf%mutex_classes_lost"</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> Variable_name <span class="token punctuation">|</span> Value <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> Performance_schema_mutex_classes_lost <span class="token punctuation">|</span> 10 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output">1 row in set (0.10 sec)</span></code></pre>
</div>
<p>
The instrumentation still works and collects (partial) data for
<code class="literal">
plugin_b
</code>
.
</p>
<p>
When the server cannot create a mutex instrument, these results
occur:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
No row for the instrument is inserted into the
<a class="link" href="performance-schema-setup-instruments-table.html" title="29.12.2.3 The setup_instruments Table">
<code class="literal">
setup_instruments
</code>
</a>
table.
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="performance-schema-status-variables.html#statvar_Performance_schema_mutex_classes_lost">
<code class="literal">
Performance_schema_mutex_classes_lost
</code>
</a>
increases by 1.
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="performance-schema-status-variables.html#statvar_Performance_schema_mutex_instances_lost">
<code class="literal">
Performance_schema_mutex_instances_lost
</code>
</a>
does not change. (When the mutex instrument is not created, it
cannot be used to create instrumented mutex instances later.)
</p>
</li>
</ul>
</div>
<p>
The pattern just described applies to all types of instruments,
not just mutexes.
</p>
<p>
A value of
<a class="link" href="performance-schema-status-variables.html#statvar_Performance_schema_mutex_classes_lost">
<code class="literal">
Performance_schema_mutex_classes_lost
</code>
</a>
greater than 0 can happen in two cases:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
To save a few bytes of memory, you start the server with
<a class="link" href="performance-schema-system-variables.html#sysvar_performance_schema_max_mutex_classes">
<code class="option">
--performance_schema_max_mutex_classes=
<em class="replaceable">
<code>
N
</code>
</em>
</code>
</a>
,
where
<em class="replaceable">
<code>
N
</code>
</em>
is less than the default
value. The default value is chosen to be sufficient to load
all the plugins provided in the MySQL distribution, but this
can be reduced if some plugins are never loaded. For example,
you might choose not to load some of the storage engines in
the distribution.
</p>
</li>
<li class="listitem">
<p>
You load a third-party plugin that is instrumented for the
Performance Schema but do not allow for the plugin's
instrumentation memory requirements when you start the server.
Because it comes from a third party, the instrument memory
consumption of this engine is not accounted for in the default
value chosen for
<a class="link" href="performance-schema-system-variables.html#sysvar_performance_schema_max_mutex_classes">
<code class="literal">
performance_schema_max_mutex_classes
</code>
</a>
.
</p>
<p>
If the server has insufficient resources for the plugin's
instruments and you do not explicitly allocate more using
<a class="link" href="performance-schema-system-variables.html#sysvar_performance_schema_max_mutex_classes">
<code class="option">
--performance_schema_max_mutex_classes=
<em class="replaceable">
<code>
N
</code>
</em>
</code>
</a>
,
loading the plugin leads to starvation of instruments.
</p>
</li>
</ul>
</div>
<p>
If the value chosen for
<a class="link" href="performance-schema-system-variables.html#sysvar_performance_schema_max_mutex_classes">
<code class="literal">
performance_schema_max_mutex_classes
</code>
</a>
is too small, no error is reported in the error log and there is
no failure at runtime. However, the content of the tables in the
<code class="literal">
performance_schema
</code>
database misses events. The
<a class="link" href="performance-schema-status-variables.html#statvar_Performance_schema_mutex_classes_lost">
<code class="literal">
Performance_schema_mutex_classes_lost
</code>
</a>
status variable is the only visible sign to indicate that some
events were dropped internally due to failure to create
instruments.
</p>
<p>
If an instrument is not lost, it is known to the Performance
Schema, and is used when instrumenting instances. For example,
<code class="literal">
wait/synch/mutex/sql/LOCK_delete
</code>
is the name of
a mutex instrument in the
<a class="link" href="performance-schema-setup-instruments-table.html" title="29.12.2.3 The setup_instruments Table">
<code class="literal">
setup_instruments
</code>
</a>
table. This single
instrument is used when creating a mutex in the code (in
<code class="literal">
THD::LOCK_delete
</code>
) however many instances of the
mutex are needed as the server runs. In this case,
<code class="literal">
LOCK_delete
</code>
is a mutex that is per connection
(
<code class="literal">
THD
</code>
), so if a server has 1000 connections,
there are 1000 threads, and 1000 instrumented
<code class="literal">
LOCK_delete
</code>
mutex instances
(
<code class="literal">
THD::LOCK_delete
</code>
).
</p>
<p>
If the server does not have room for all these 1000 instrumented
mutexes (instances), some mutexes are created with
instrumentation, and some are created without instrumentation. If
the server can create only 800 instances, 200 instances are lost.
The server continues to run, but increments
<a class="link" href="performance-schema-status-variables.html#statvar_Performance_schema_mutex_instances_lost">
<code class="literal">
Performance_schema_mutex_instances_lost
</code>
</a>
by 200 to indicate that instances could not be created.
</p>
<p>
A value of
<a class="link" href="performance-schema-status-variables.html#statvar_Performance_schema_mutex_instances_lost">
<code class="literal">
Performance_schema_mutex_instances_lost
</code>
</a>
greater than 0 can happen when the code initializes more mutexes
at runtime than were allocated for
<a class="link" href="performance-schema-system-variables.html#sysvar_performance_schema_max_mutex_instances">
<code class="option">
--performance_schema_max_mutex_instances=
<em class="replaceable">
<code>
N
</code>
</em>
</code>
</a>
.
</p>
<p>
The bottom line is that if
<a class="link" href="show-status.html" title="15.7.7.37 SHOW STATUS Statement">
<code class="literal">
SHOW STATUS LIKE
'perf%'
</code>
</a>
says that nothing was lost (all values are
zero), the Performance Schema data is accurate and can be relied
upon. If something was lost, the data is incomplete, and the
Performance Schema could not record everything given the
insufficient amount of memory it was given to use. In this case,
the specific
<code class="literal">
Performance_schema_
<em class="replaceable">
<code>
xxx
</code>
</em>
_lost
</code>
variable indicates the problem area.
</p>
<p>
It might be appropriate in some cases to cause deliberate
instrument starvation. For example, if you do not care about
performance data for file I/O, you can start the server with all
Performance Schema parameters related to file I/O set to 0. No
memory is allocated for file-related classes, instances, or
handles, and all file events are lost.
</p>
<p>
Use
<a class="link" href="show-engine.html" title="15.7.7.16 SHOW ENGINE Statement">
<code class="literal">
SHOW ENGINE
PERFORMANCE_SCHEMA STATUS
</code>
</a>
to inspect the internal
operation of the Performance Schema code:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa33458433"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SHOW</span> <span class="token keyword">ENGINE</span> PERFORMANCE_SCHEMA <span class="token keyword">STATUS</span>\G
<span class="token punctuation">.</span><span class="token punctuation">.</span><span class="token punctuation">.</span>
<span class="token output"><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span> 3. row <span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span>
Type<span class="token punctuation">:</span> performance_schema
Name<span class="token punctuation">:</span> events_waits_history.size
Status<span class="token punctuation">:</span> 76
<span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span> 4. row <span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span>
Type<span class="token punctuation">:</span> performance_schema
Name<span class="token punctuation">:</span> events_waits_history.count
Status<span class="token punctuation">:</span> 10000
<span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span> 5. row <span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span>
Type<span class="token punctuation">:</span> performance_schema
Name<span class="token punctuation">:</span> events_waits_history.memory
Status<span class="token punctuation">:</span> 760000
...
<span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span> 57. row <span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span>
Type<span class="token punctuation">:</span> performance_schema
Name<span class="token punctuation">:</span> performance_schema.memory
Status<span class="token punctuation">:</span> 26459600
...</span></code></pre>
</div>
<p>
This statement is intended to help the DBA understand the effects
that different Performance Schema options have on memory
requirements. For a description of the field meanings, see
<a class="xref" href="show-engine.html" title="15.7.7.16 SHOW ENGINE Statement">
Section 15.7.7.16, “SHOW ENGINE Statement”
</a>
.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/mysql-gr-memory-monitoring-ps-instruments-enable.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="mysql-gr-memory-monitoring-ps-instruments-enable">
</a>
20.7.9.1 Enabling or Disabling Group Replication Instrumentation
</h4>
</div>
</div>
</div>
<p>
To enable all the Group Replication instrumentation from the
command line, run the following in the SQL client of your
choice:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa54256874"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"> <span class="token keyword">UPDATE</span> performance_schema<span class="token punctuation">.</span>setup_instruments <span class="token keyword">SET</span> ENABLED <span class="token operator">=</span> <span class="token string">'YES'</span>
<span class="token keyword">WHERE</span> <span class="token keyword">NAME</span> <span class="token operator">LIKE</span> <span class="token string">'memory/group_rpl/%'</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
To disable all the Group Replication instrumentation from the
command line, run the following in the SQL client of your
choice:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa60819223"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"> <span class="token keyword">UPDATE</span> performance_schema<span class="token punctuation">.</span>setup_instruments <span class="token keyword">SET</span> ENABLED <span class="token operator">=</span> <span class="token string">'NO'</span>
<span class="token keyword">WHERE</span> <span class="token keyword">NAME</span> <span class="token operator">LIKE</span> <span class="token string">'memory/group_rpl/%'</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
To enable all the Group Replication instrumentation at server
startup, add the following to your option file:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-ini"><div class="docs-select-all right" id="sa33015791"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-ini"><span class="token selector"> [mysqld]</span>
<span class="token constant"> performance-schema-instrument</span><span class="token attr-value"><span class="token punctuation">=</span>'memory/group_rpl/%=ON'</span></code></pre>
</div>
<p>
To disable all the Group Replication instrumentation at server
startup, add the following to your option file:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-ini"><div class="docs-select-all right" id="sa92544653"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-ini"><span class="token selector"> [mysqld]</span>
<span class="token constant"> performance-schema-instrument</span><span class="token attr-value"><span class="token punctuation">=</span>'memory/group_rpl/%=OFF'</span></code></pre>
</div>
<p>
To enable or disable individual instruments in that group,
replace the wildcard (%) with the full name of the instrument.
</p>
<p>
For more information, see
<a class="xref" href="performance-schema-startup-configuration.html" title="29.3 Performance Schema Startup Configuration">
Section 29.3, “Performance Schema Startup Configuration”
</a>
and
<a class="xref" href="performance-schema-runtime-configuration.html" title="29.4 Performance Schema Runtime Configuration">
Section 29.4, “Performance Schema Runtime Configuration”
</a>
.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/constraint-foreign-key.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="constraint-foreign-key">
</a>
1.7.3.2 FOREIGN KEY Constraints
</h4>
</div>
</div>
</div>
<a class="indexterm" name="idm46045333127456">
</a>
<p>
Foreign keys let you cross-reference related data across
tables, and
<a class="link" href="glossary.html#glos_foreign_key_constraint" title="FOREIGN KEY constraint">
foreign key
constraints
</a>
help keep this spread-out data consistent.
</p>
<p>
MySQL supports
<code class="literal">
ON UPDATE
</code>
and
<code class="literal">
ON
DELETE
</code>
foreign key references in
<a class="link" href="create-table.html" title="15.1.20 CREATE TABLE Statement">
<code class="literal">
CREATE TABLE
</code>
</a>
and
<a class="link" href="alter-table.html" title="15.1.9 ALTER TABLE Statement">
<code class="literal">
ALTER TABLE
</code>
</a>
statements. The
available referential actions are
<code class="literal">
RESTRICT
</code>
,
<code class="literal">
CASCADE
</code>
,
<code class="literal">
SET NULL
</code>
, and
<code class="literal">
NO ACTION
</code>
(the default).
</p>
<p>
<code class="literal">
SET DEFAULT
</code>
is also supported by the MySQL
Server but is currently rejected as invalid by
<a class="link" href="innodb-storage-engine.html" title="Chapter 17 The InnoDB Storage Engine">
<code class="literal">
InnoDB
</code>
</a>
. Since MySQL does not
support deferred constraint checking,
<code class="literal">
NO
ACTION
</code>
is treated as
<code class="literal">
RESTRICT
</code>
.
For the exact syntax supported by MySQL for foreign keys, see
<a class="xref" href="create-table-foreign-keys.html" title="15.1.20.5 FOREIGN KEY Constraints">
Section 15.1.20.5, “FOREIGN KEY Constraints”
</a>
.
</p>
<p>
<code class="literal">
MATCH FULL
</code>
,
<code class="literal">
MATCH
PARTIAL
</code>
, and
<code class="literal">
MATCH SIMPLE
</code>
are
allowed, but their use should be avoided, as they cause the
MySQL Server to ignore any
<code class="literal">
ON DELETE
</code>
or
<code class="literal">
ON UPDATE
</code>
clause used in the same
statement.
<code class="literal">
MATCH
</code>
options do not have any
other effect in MySQL, which in effect enforces
<code class="literal">
MATCH
SIMPLE
</code>
semantics full-time.
</p>
<p>
MySQL requires that foreign key columns be indexed; if you
create a table with a foreign key constraint but no index on a
given column, an index is created.
</p>
<p>
You can obtain information about foreign keys from the
Information Schema
<a class="link" href="information-schema-key-column-usage-table.html" title="28.3.16 The INFORMATION_SCHEMA KEY_COLUMN_USAGE Table">
<code class="literal">
KEY_COLUMN_USAGE
</code>
</a>
table. An
example of a query against this table is shown here:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa12569565"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> TABLE_SCHEMA<span class="token punctuation">,</span> <span class="token keyword">TABLE_NAME</span><span class="token punctuation">,</span> <span class="token keyword">COLUMN_NAME</span><span class="token punctuation">,</span> <span class="token keyword">CONSTRAINT_NAME</span>
<span class="token operator">></span> <span class="token keyword">FROM</span> INFORMATION_SCHEMA<span class="token punctuation">.</span>KEY_COLUMN_USAGE
<span class="token operator">></span> <span class="token keyword">WHERE</span> REFERENCED_TABLE_SCHEMA <span class="token operator">IS</span> <span class="token operator">NOT</span> <span class="token boolean">NULL</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> TABLE_SCHEMA <span class="token punctuation">|</span> TABLE_NAME <span class="token punctuation">|</span> COLUMN_NAME <span class="token punctuation">|</span> CONSTRAINT_NAME <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> fk1 <span class="token punctuation">|</span> myuser <span class="token punctuation">|</span> myuser_id <span class="token punctuation">|</span> f <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> fk1 <span class="token punctuation">|</span> product_order <span class="token punctuation">|</span> customer_id <span class="token punctuation">|</span> f2 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> fk1 <span class="token punctuation">|</span> product_order <span class="token punctuation">|</span> product_id <span class="token punctuation">|</span> f1 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output">3 rows in set (0.01 sec)</span></code></pre>
</div>
<p>
Information about foreign keys on
<code class="literal">
InnoDB
</code>
tables can also be found in the
<a class="link" href="information-schema-innodb-foreign-table.html" title="28.4.12 The INFORMATION_SCHEMA INNODB_FOREIGN Table">
<code class="literal">
INNODB_FOREIGN
</code>
</a>
and
<a class="link" href="information-schema-innodb-foreign-cols-table.html" title="28.4.13 The INFORMATION_SCHEMA INNODB_FOREIGN_COLS Table">
<code class="literal">
INNODB_FOREIGN_COLS
</code>
</a>
tables, in
the
<code class="literal">
INFORMATION_SCHEMA
</code>
database.
</p>
<p>
<code class="literal">
InnoDB
</code>
and
<code class="literal">
NDB
</code>
tables
support foreign keys.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/creating-database.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="creating-database">
</a>
5.3.1 Creating and Selecting a Database
</h3>
</div>
</div>
</div>
<a class="indexterm" name="idm46045325483680">
</a>
<a class="indexterm" name="idm46045325482224">
</a>
<p>
If the administrator creates your database for you when setting
up your permissions, you can begin using it. Otherwise, you need
to create it yourself:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-sql"><div class="docs-select-all right" id="sa56031372"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">CREATE</span> <span class="token keyword">DATABASE</span> menagerie<span class="token punctuation">;</span></code></pre>
</div>
<p>
Under Unix, database names are case-sensitive (unlike SQL
keywords), so you must always refer to your database as
<code class="literal">
menagerie
</code>
, not as
<code class="literal">
Menagerie
</code>
,
<code class="literal">
MENAGERIE
</code>
, or
some other variant. This is also true for table names. (Under
Windows, this restriction does not apply, although you must
refer to databases and tables using the same lettercase
throughout a given query. However, for a variety of reasons, the
recommended best practice is always to use the same lettercase
that was used when the database was created.)
</p>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Note
</div>
<p>
If you get an error such as
<span class="errortext">
ERROR 1044 (42000):
Access denied for user 'micah'@'localhost' to database
'menagerie'
</span>
when attempting to create a database,
this means that your user account does not have the necessary
privileges to do so. Discuss this with the administrator or
see
<a class="xref" href="access-control.html" title="8.2 Access Control and Account Management">
Section 8.2, “Access Control and Account Management”
</a>
.
</p>
</div>
<p>
Creating a database does not select it for use; you must do that
explicitly. To make
<code class="literal">
menagerie
</code>
the current
database, use this statement:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa34242085"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">USE</span> menagerie
<span class="token keyword">Database</span> <span class="token keyword">changed</span></code></pre>
</div>
<p>
Your database needs to be created only once, but you must select
it for use each time you begin a
<a class="link" href="mysql.html" title="6.5.1 mysql — The MySQL Command-Line Client">
<span class="command">
<strong>
mysql
</strong>
</span>
</a>
session. You can do this by issuing a
<a class="link" href="use.html" title="15.8.4 USE Statement">
<code class="literal">
USE
</code>
</a>
statement as shown in the
example. Alternatively, you can select the database on the
command line when you invoke
<a class="link" href="mysql.html" title="6.5.1 mysql — The MySQL Command-Line Client">
<span class="command">
<strong>
mysql
</strong>
</span>
</a>
. Just
specify its name after any connection parameters that you might
need to provide. For example:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-terminal"><div class="docs-select-all right" id="sa98289492"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal"><span class="token prompt">$> </span><span class="token command">mysql</span> <span class="token property">-h</span> <em class="replaceable">host</em> <span class="token property">-u</span> <em class="replaceable">user</em> <span class="token property">-p</span> menagerie
Enter password<span class="token punctuation">:</span> ********</code></pre>
</div>
<div class="important" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Important
</div>
<p>
<code class="literal">
menagerie
</code>
in the command just shown is
<span class="bold">
<strong>
not
</strong>
</span>
your password. If you
want to supply your password on the command line after the
<code class="literal">
-p
</code>
option, you must do so with no
intervening space (for example, as
<code class="literal">
-p
<em class="replaceable">
<code>
password
</code>
</em>
</code>
, not
as
<code class="literal">
-p
<em class="replaceable">
<code>
password
</code>
</em>
</code>
).
However, putting your password on the command line is not
recommended, because doing so exposes it to snooping by other
users logged in on your machine.
</p>
</div>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Note
</div>
<p>
You can see at any time which database is currently selected
using
<a class="link" href="select.html" title="15.2.13 SELECT Statement">
<code class="literal">
SELECT
</code>
</a>
<a class="link" href="information-functions.html#function_database">
<code class="literal">
DATABASE()
</code>
</a>
.
</p>
</div>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/multiple-tables.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="multiple-tables">
</a>
5.3.4.9 Using More Than one Table
</h4>
</div>
</div>
</div>
<a class="indexterm" name="idm46045324937088">
</a>
<p>
The
<code class="literal">
pet
</code>
table keeps track of which pets you
have. If you want to record other information about them, such
as events in their lives like visits to the vet or when
litters are born, you need another table. What should this
table look like? It needs to contain the following
information:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
The pet name so that you know which animal each event
pertains to.
</p>
</li>
<li class="listitem">
<p>
A date so that you know when the event occurred.
</p>
</li>
<li class="listitem">
<p>
A field to describe the event.
</p>
</li>
<li class="listitem">
<p>
An event type field, if you want to be able to categorize
events.
</p>
</li>
</ul>
</div>
<p>
Given these considerations, the
<a class="link" href="create-table.html" title="15.1.20 CREATE TABLE Statement">
<code class="literal">
CREATE
TABLE
</code>
</a>
statement for the
<code class="literal">
event
</code>
table might look like this:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa54444146"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">CREATE</span> <span class="token keyword">TABLE</span> <span class="token keyword">event</span> <span class="token punctuation">(</span><span class="token keyword">name</span> <span class="token datatype">VARCHAR</span><span class="token punctuation">(</span><span class="token number">20</span><span class="token punctuation">)</span><span class="token punctuation">,</span> <span class="token datatype">date</span> <span class="token datatype">DATE</span><span class="token punctuation">,</span>
<span class="token keyword">type</span> <span class="token datatype">VARCHAR</span><span class="token punctuation">(</span><span class="token number">15</span><span class="token punctuation">)</span><span class="token punctuation">,</span> remark <span class="token datatype">VARCHAR</span><span class="token punctuation">(</span><span class="token number">255</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
As with the
<code class="literal">
pet
</code>
table, it is easiest to
load the initial records by creating a tab-delimited text file
containing the following information.
</p>
<div class="informaltable">
<table summary="pet record data that appears in a tab delimited text file, as described in the preceding text.">
<colgroup>
<col style="width: 15%"/>
<col style="width: 15%"/>
<col style="width: 15%"/>
<col style="width: 35%"/>
</colgroup>
<thead>
<tr>
<th scope="col">
name
</th>
<th scope="col">
date
</th>
<th scope="col">
type
</th>
<th scope="col">
remark
</th>
</tr>
</thead>
<tbody>
<tr>
<th scope="row">
Fluffy
</th>
<td>
1995-05-15
</td>
<td>
litter
</td>
<td>
4 kittens, 3 female, 1 male
</td>
</tr>
<tr>
<th scope="row">
Buffy
</th>
<td>
1993-06-23
</td>
<td>
litter
</td>
<td>
5 puppies, 2 female, 3 male
</td>
</tr>
<tr>
<th scope="row">
Buffy
</th>
<td>
1994-06-19
</td>
<td>
litter
</td>
<td>
3 puppies, 3 female
</td>
</tr>
<tr>
<th scope="row">
Chirpy
</th>
<td>
1999-03-21
</td>
<td>
vet
</td>
<td>
needed beak straightened
</td>
</tr>
<tr>
<th scope="row">
Slim
</th>
<td>
1997-08-03
</td>
<td>
vet
</td>
<td>
broken rib
</td>
</tr>
<tr>
<th scope="row">
Bowser
</th>
<td>
1991-10-12
</td>
<td>
kennel
</td>
<td>
</td>
</tr>
<tr>
<th scope="row">
Fang
</th>
<td>
1991-10-12
</td>
<td>
kennel
</td>
<td>
</td>
</tr>
<tr>
<th scope="row">
Fang
</th>
<td>
1998-08-28
</td>
<td>
birthday
</td>
<td>
Gave him a new chew toy
</td>
</tr>
<tr>
<th scope="row">
Claws
</th>
<td>
1998-03-17
</td>
<td>
birthday
</td>
<td>
Gave him a new flea collar
</td>
</tr>
<tr>
<th scope="row">
Whistler
</th>
<td>
1998-12-09
</td>
<td>
birthday
</td>
<td>
First birthday
</td>
</tr>
</tbody>
</table>
</div>
<div class="informaltable">
<table cellpadding="0" cellspacing="0" style="position: fixed; top: 0px; display: none; left: 401px; width: 519px;">
<thead>
<tr>
<th scope="col" style="width: 97.0625px;">
name
</th>
<th scope="col" style="width: 97.0625px;">
date
</th>
<th scope="col" style="width: 97.0625px;">
type
</th>
<th scope="col" style="width: 226.516px;">
remark
</th>
</tr>
</thead>
</table>
</div>
<p>
Load the records like this:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-sql"><div class="docs-select-all right" id="sa75601629"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">LOAD</span> <span class="token keyword">DATA</span> <span class="token keyword">LOCAL</span> <span class="token keyword">INFILE</span> <span class="token string">'event.txt'</span> <span class="token keyword">INTO</span> <span class="token keyword">TABLE</span> <span class="token keyword">event</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
Based on what you have learned from the queries that you have
run on the
<code class="literal">
pet
</code>
table, you should be able to
perform retrievals on the records in the
<code class="literal">
event
</code>
table; the principles are the same.
But when is the
<code class="literal">
event
</code>
table by itself
insufficient to answer questions you might ask?
</p>
<p>
Suppose that you want to find out the ages at which each pet
had its litters. We saw earlier how to calculate ages from two
dates. The litter date of the mother is in the
<code class="literal">
event
</code>
table, but to calculate her age on
that date you need her birth date, which is stored in the
<code class="literal">
pet
</code>
table. This means the query requires
both tables:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa77338655"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> pet<span class="token punctuation">.</span><span class="token keyword">name</span><span class="token punctuation">,</span>
<span class="token function">TIMESTAMPDIFF</span><span class="token punctuation">(</span><span class="token datatype">YEAR</span><span class="token punctuation">,</span>birth<span class="token punctuation">,</span><span class="token datatype">date</span><span class="token punctuation">)</span> <span class="token keyword">AS</span> age<span class="token punctuation">,</span>
remark
<span class="token keyword">FROM</span> pet <span class="token keyword">INNER</span> <span class="token keyword">JOIN</span> <span class="token keyword">event</span>
<span class="token keyword">ON</span> pet<span class="token punctuation">.</span><span class="token keyword">name</span> <span class="token operator">=</span> <span class="token keyword">event</span><span class="token punctuation">.</span><span class="token keyword">name</span>
<span class="token keyword">WHERE</span> <span class="token keyword">event</span><span class="token punctuation">.</span><span class="token keyword">type</span> <span class="token operator">=</span> <span class="token string">'litter'</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> name <span class="token punctuation">|</span> age <span class="token punctuation">|</span> remark <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> Fluffy <span class="token punctuation">|</span> 2 <span class="token punctuation">|</span> 4 kittens, 3 female, 1 male <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> Buffy <span class="token punctuation">|</span> 4 <span class="token punctuation">|</span> 5 puppies, 2 female, 3 male <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> Buffy <span class="token punctuation">|</span> 5 <span class="token punctuation">|</span> 3 puppies, 3 female <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span></code></pre>
</div>
<p>
There are several things to note about this query:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
The
<code class="literal">
FROM
</code>
clause joins two tables
because the query needs to pull information from both of
them.
</p>
</li>
<li class="listitem">
<p>
When combining (joining) information from multiple tables,
you need to specify how records in one table can be
matched to records in the other. This is easy because they
both have a
<code class="literal">
name
</code>
column. The query uses
an
<code class="literal">
ON
</code>
clause to match up records in the
two tables based on the
<code class="literal">
name
</code>
values.
</p>
<p>
The query uses an
<code class="literal">
INNER JOIN
</code>
to combine
the tables. An
<code class="literal">
INNER JOIN
</code>
permits rows
from either table to appear in the result if and only if
both tables meet the conditions specified in the
<code class="option">
ON
</code>
clause. In this example, the
<code class="literal">
ON
</code>
clause specifies that the
<code class="literal">
name
</code>
column in the
<code class="literal">
pet
</code>
table must match the
<code class="literal">
name
</code>
column in the
<code class="literal">
event
</code>
table. If a name appears in one
table but not the other, the row does not appear in the
result because the condition in the
<code class="literal">
ON
</code>
clause fails.
</p>
</li>
<li class="listitem">
<p>
Because the
<code class="literal">
name
</code>
column occurs in both
tables, you must be specific about which table you mean
when referring to the column. This is done by prepending
the table name to the column name.
</p>
</li>
</ul>
</div>
<p>
You need not have two different tables to perform a join.
Sometimes it is useful to join a table to itself, if you want
to compare records in a table to other records in that same
table. For example, to find breeding pairs among your pets,
you can join the
<code class="literal">
pet
</code>
table with itself to
produce candidate pairs of live males and females of like
species:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa55842120"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> p1<span class="token punctuation">.</span><span class="token keyword">name</span><span class="token punctuation">,</span> p1<span class="token punctuation">.</span>sex<span class="token punctuation">,</span> p2<span class="token punctuation">.</span><span class="token keyword">name</span><span class="token punctuation">,</span> p2<span class="token punctuation">.</span>sex<span class="token punctuation">,</span> p1<span class="token punctuation">.</span>species
<span class="token keyword">FROM</span> pet <span class="token keyword">AS</span> p1 <span class="token keyword">INNER</span> <span class="token keyword">JOIN</span> pet <span class="token keyword">AS</span> p2
<span class="token keyword">ON</span> p1<span class="token punctuation">.</span>species <span class="token operator">=</span> p2<span class="token punctuation">.</span>species
<span class="token operator">AND</span> p1<span class="token punctuation">.</span>sex <span class="token operator">=</span> <span class="token string">'f'</span> <span class="token operator">AND</span> p1<span class="token punctuation">.</span>death <span class="token operator">IS</span> <span class="token boolean">NULL</span>
<span class="token operator">AND</span> p2<span class="token punctuation">.</span>sex <span class="token operator">=</span> <span class="token string">'m'</span> <span class="token operator">AND</span> p2<span class="token punctuation">.</span>death <span class="token operator">IS</span> <span class="token boolean">NULL</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> name <span class="token punctuation">|</span> sex <span class="token punctuation">|</span> name <span class="token punctuation">|</span> sex <span class="token punctuation">|</span> species <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> Fluffy <span class="token punctuation">|</span> f <span class="token punctuation">|</span> Claws <span class="token punctuation">|</span> m <span class="token punctuation">|</span> cat <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> Buffy <span class="token punctuation">|</span> f <span class="token punctuation">|</span> Fang <span class="token punctuation">|</span> m <span class="token punctuation">|</span> dog <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span></code></pre>
</div>
<p>
In this query, we specify aliases for the table name to refer
to the columns and keep straight which instance of the table
each column reference is associated with.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-ndbinfo-membership.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="mysql-cluster-ndbinfo-membership">
</a>
25.6.17.45 The ndbinfo membership Table
</h4>
</div>
</div>
</div>
<a class="indexterm" name="idm46045088954768">
</a>
<p>
The
<code class="literal">
membership
</code>
table describes the view that
each data node has of all the others in the cluster, including
node group membership, president node, arbitrator, arbitrator
successor, arbitrator connection states, and other information.
</p>
<p>
The
<code class="literal">
membership
</code>
table contains the following
columns:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<code class="literal">
node_id
</code>
</p>
<p>
This node's node ID
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
group_id
</code>
</p>
<p>
Node group to which this node belongs
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
left node
</code>
</p>
<p>
Node ID of the previous node
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
right_node
</code>
</p>
<p>
Node ID of the next node
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
president
</code>
</p>
<p>
President's node ID
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
successor
</code>
</p>
<p>
Node ID of successor to president
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
succession_order
</code>
</p>
<p>
Order in which this node succeeds to presidency
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Conf_HB_order
</code>
</p>
<p>
-
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
arbitrator
</code>
</p>
<p>
Node ID of arbitrator
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
arb_ticket
</code>
</p>
<p>
Internal identifier used to track arbitration
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
arb_state
</code>
</p>
<p>
Arbitration state
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
arb_connected
</code>
</p>
<p>
Whether this node is connected to the arbitrator; either of
<code class="literal">
Yes
</code>
or
<code class="literal">
No
</code>
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
connected_rank1_arbs
</code>
</p>
<p>
Connected arbitrators of rank 1
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
connected_rank2_arbs
</code>
</p>
<p>
Connected arbitrators of rank 1
</p>
</li>
</ul>
</div>
<h5>
<a name="idm46045088922272">
</a>
Notes
</h5>
<p>
The node ID and node group ID are the same as reported by
<a class="link" href="mysql-cluster-programs-ndb-mgm.html" title="25.5.5 ndb_mgm — The NDB Cluster Management Client">
<span class="command">
<strong>
ndb_mgm -e "SHOW"
</strong>
</span>
</a>
.
</p>
<p>
<code class="literal">
left_node
</code>
and
<code class="literal">
right_node
</code>
are defined in terms of a model that connects all data nodes in
a circle, in order of their node IDs, similar to the ordering of
the numbers on a clock dial, as shown here:
</p>
<div class="figure">
<a name="fig-mysql-cluster-circular-left-right">
</a>
<p class="title">
<b>
Figure 25.6 Circular Arrangement of NDB Cluster Nodes
</b>
</p>
<div class="figure-contents">
<div class="mediaobject">
<img alt="Content is described in the surrounding text." src="images/cluster-left-right.png" style="width: 100%; max-width: 300px;"/>
</div>
</div>
</div>
<br class="figure-break"/>
<p>
In this example, we have 8 data nodes, numbered 5, 6, 7, 8, 12,
13, 14, and 15, ordered clockwise in a circle. We determine
<span class="quote">
“
<span class="quote">
left
</span>
”
</span>
and
<span class="quote">
“
<span class="quote">
right
</span>
”
</span>
from the interior
of the circle. The node to the left of node 5 is node 15, and
the node to the right of node 5 is node 6. You can see all these
relationships by running the following query and observing the
output:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa66936502"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> node_id<span class="token punctuation">,</span>left_node<span class="token punctuation">,</span>right_node
<span class="token prompt"> -></span> <span class="token keyword">FROM</span> ndbinfo<span class="token punctuation">.</span>membership<span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> node_id <span class="token punctuation">|</span> left_node <span class="token punctuation">|</span> right_node <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> 5 <span class="token punctuation">|</span> 15 <span class="token punctuation">|</span> 6 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> 6 <span class="token punctuation">|</span> 5 <span class="token punctuation">|</span> 7 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> 7 <span class="token punctuation">|</span> 6 <span class="token punctuation">|</span> 8 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> 8 <span class="token punctuation">|</span> 7 <span class="token punctuation">|</span> 12 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> 12 <span class="token punctuation">|</span> 8 <span class="token punctuation">|</span> 13 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> 13 <span class="token punctuation">|</span> 12 <span class="token punctuation">|</span> 14 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> 14 <span class="token punctuation">|</span> 13 <span class="token punctuation">|</span> 15 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> 15 <span class="token punctuation">|</span> 14 <span class="token punctuation">|</span> 5 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output">8 rows in set (0.00 sec)</span></code></pre>
</div>
<p>
The designations
<span class="quote">
“
<span class="quote">
left
</span>
”
</span>
and
<span class="quote">
“
<span class="quote">
right
</span>
”
</span>
are used in the event log in the same way.
</p>
<p>
The
<code class="literal">
president
</code>
node is the node viewed by the
current node as responsible for setting an arbitrator (see
<a class="ulink" href="/doc/ndb-internals/en/ndb-internals-start-phases.html" target="_top">
NDB Cluster Start Phases
</a>
). If the president
fails or becomes disconnected, the current node expects the node
whose ID is shown in the
<code class="literal">
successor
</code>
column to
become the new president. The
<code class="literal">
succession_order
</code>
column shows the place in
the succession queue that the current node views itself as
having.
</p>
<p>
In a normal NDB Cluster, all data nodes should see the same node
as
<code class="literal">
president
</code>
, and the same node (other than
the president) as its
<code class="literal">
successor
</code>
. In addition,
the current president should see itself as
<code class="literal">
1
</code>
in the order of succession, the
<code class="literal">
successor
</code>
node should see itself as
<code class="literal">
2
</code>
, and so on.
</p>
<p>
All nodes should show the same
<code class="literal">
arb_ticket
</code>
values as well as the same
<code class="literal">
arb_state
</code>
values.
Possible
<code class="literal">
arb_state
</code>
values are
<code class="literal">
ARBIT_NULL
</code>
,
<code class="literal">
ARBIT_INIT
</code>
,
<code class="literal">
ARBIT_FIND
</code>
,
<code class="literal">
ARBIT_PREP1
</code>
,
<code class="literal">
ARBIT_PREP2
</code>
,
<code class="literal">
ARBIT_START
</code>
,
<code class="literal">
ARBIT_RUN
</code>
,
<code class="literal">
ARBIT_CHOOSE
</code>
,
<code class="literal">
ARBIT_CRASH
</code>
, and
<code class="literal">
UNKNOWN
</code>
.
</p>
<p>
<code class="literal">
arb_connected
</code>
shows whether this node is
connected to the node shown as this node's
<code class="literal">
arbitrator
</code>
.
</p>
<p>
The
<code class="literal">
connected_rank1_arbs
</code>
and
<code class="literal">
connected_rank2_arbs
</code>
columns each display a
list of 0 or more arbitrators having an
<a class="link" href="mysql-cluster-mgm-definition.html#ndbparam-mgmd-arbitrationrank">
<code class="literal">
ArbitrationRank
</code>
</a>
equal to
1, or to 2, respectively.
</p>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Note
</div>
<p>
Both management nodes and API nodes are eligible to become
arbitrators.
</p>
</div>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/adding-collation-simple-8bit.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="adding-collation-simple-8bit">
</a>
12.14.3 Adding a Simple Collation to an 8-Bit Character Set
</h3>
</div>
</div>
</div>
<p>
This section describes how to add a simple collation for an
8-bit character set by writing the
<code class="literal">
<collation>
</code>
elements associated with a
<code class="literal">
<charset>
</code>
character set description in
the MySQL
<code class="filename">
Index.xml
</code>
file. The procedure
described here does not require recompiling MySQL. The example
adds a collation named
<code class="literal">
latin1_test_ci
</code>
to the
<code class="literal">
latin1
</code>
character set.
</p>
<div class="orderedlist">
<ol class="orderedlist" type="1">
<li class="listitem">
<p>
Choose a collation ID, as shown in
<a class="xref" href="adding-collation-choosing-id.html" title="12.14.2 Choosing a Collation ID">
Section 12.14.2, “Choosing a Collation ID”
</a>
. The
following steps use an ID of 1024.
</p>
</li>
<li class="listitem">
<p>
Modify the
<code class="literal">
Index.xml
</code>
and
<code class="literal">
latin1.xml
</code>
configuration files. These
files are located in the directory named by the
<a class="link" href="server-system-variables.html#sysvar_character_sets_dir">
<code class="literal">
character_sets_dir
</code>
</a>
system
variable. You can check the variable value as follows,
although the path name might be different on your system:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa2893684"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SHOW</span> <span class="token keyword">VARIABLES</span> <span class="token operator">LIKE</span> <span class="token string">'character_sets_dir'</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> Variable_name <span class="token punctuation">|</span> Value <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> character_sets_dir <span class="token punctuation">|</span> /user/local/mysql/share/mysql/charsets/ <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span></code></pre>
</div>
</li>
<li class="listitem">
<p>
Choose a name for the collation and list it in the
<code class="filename">
Index.xml
</code>
file. Find the
<code class="literal">
<charset>
</code>
element for the character
set to which the collation is being added, and add a
<code class="literal">
<collation>
</code>
element that indicates
the collation name and ID, to associate the name with the
ID. For example:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-xml"><div class="docs-select-all right" id="sa1235698"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-xml"><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>charset</span> <span class="token attr-name">name</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>latin1<span class="token punctuation">"</span></span><span class="token punctuation">></span></span>
...
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>collation</span> <span class="token attr-name">name</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>latin1_test_ci<span class="token punctuation">"</span></span> <span class="token attr-name">id</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>1024<span class="token punctuation">"</span></span><span class="token punctuation">/></span></span>
...
<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>charset</span><span class="token punctuation">></span></span></code></pre>
</div>
</li>
<li class="listitem">
<p>
In the
<code class="filename">
latin1.xml
</code>
configuration file,
add a
<code class="literal">
<collation>
</code>
element that
names the collation and that contains a
<code class="literal">
<map>
</code>
element that defines a
character code-to-weight mapping table for character codes 0
to 255. Each value within the
<code class="literal">
<map>
</code>
element must be a number in hexadecimal format.
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-xml"><div class="docs-select-all right" id="sa81667505"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-xml"><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>collation</span> <span class="token attr-name">name</span><span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">"</span>latin1_test_ci<span class="token punctuation">"</span></span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>map</span><span class="token punctuation">></span></span>
00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F
10 11 12 13 14 15 16 17 18 19 1A 1B 1C 1D 1E 1F
20 21 22 23 24 25 26 27 28 29 2A 2B 2C 2D 2E 2F
30 31 32 33 34 35 36 37 38 39 3A 3B 3C 3D 3E 3F
40 41 42 43 44 45 46 47 48 49 4A 4B 4C 4D 4E 4F
50 51 52 53 54 55 56 57 58 59 5A 5B 5C 5D 5E 5F
60 41 42 43 44 45 46 47 48 49 4A 4B 4C 4D 4E 4F
50 51 52 53 54 55 56 57 58 59 5A 7B 7C 7D 7E 7F
80 81 82 83 84 85 86 87 88 89 8A 8B 8C 8D 8E 8F
90 91 92 93 94 95 96 97 98 99 9A 9B 9C 9D 9E 9F
A0 A1 A2 A3 A4 A5 A6 A7 A8 A9 AA AB AC AD AE AF
B0 B1 B2 B3 B4 B5 B6 B7 B8 B9 BA BB BC BD BE BF
41 41 41 41 5B 5D 5B 43 45 45 45 45 49 49 49 49
44 4E 4F 4F 4F 4F 5C D7 5C 55 55 55 59 59 DE DF
41 41 41 41 5B 5D 5B 43 45 45 45 45 49 49 49 49
44 4E 4F 4F 4F 4F 5C F7 5C 55 55 55 59 59 DE FF
<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>map</span><span class="token punctuation">></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>collation</span><span class="token punctuation">></span></span></code></pre>
</div>
</li>
<li class="listitem">
<p>
Restart the server and use this statement to verify that the
collation is present:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa65340441"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SHOW</span> <span class="token keyword">COLLATION</span> <span class="token keyword">WHERE</span> <span class="token keyword">Collation</span> <span class="token operator">=</span> <span class="token string">'latin1_test_ci'</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> Collation <span class="token punctuation">|</span> Charset <span class="token punctuation">|</span> Id <span class="token punctuation">|</span> Default <span class="token punctuation">|</span> Compiled <span class="token punctuation">|</span> Sortlen <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> latin1_test_ci <span class="token punctuation">|</span> latin1 <span class="token punctuation">|</span> 1024 <span class="token punctuation">|</span> <span class="token punctuation">|</span> <span class="token punctuation">|</span> 1 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span></code></pre>
</div>
</li>
</ol>
</div>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-quick-start.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h2 class="title">
<a name="performance-schema-quick-start">
</a>
29.1 Performance Schema Quick Start
</h2>
</div>
</div>
</div>
<p>
This section briefly introduces the Performance Schema with
examples that show how to use it. For additional examples, see
<a class="xref" href="performance-schema-examples.html" title="29.19 Using the Performance Schema to Diagnose Problems">
Section 29.19, “Using the Performance Schema to Diagnose Problems”
</a>
.
</p>
<p>
The Performance Schema is enabled by default. To enable or disable
it explicitly, start the server with the
<a class="link" href="performance-schema-system-variables.html#sysvar_performance_schema">
<code class="literal">
performance_schema
</code>
</a>
variable set
to an appropriate value. For example, use these lines in the
server
<code class="filename">
my.cnf
</code>
file:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-ini"><div class="docs-select-all right" id="sa80590934"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-ini"><span class="token selector">[mysqld]</span>
<span class="token constant">performance_schema</span><span class="token attr-value"><span class="token punctuation">=</span>ON</span></code></pre>
</div>
<p>
When the server starts, it sees
<a class="link" href="performance-schema-system-variables.html#sysvar_performance_schema">
<code class="literal">
performance_schema
</code>
</a>
and attempts
to initialize the Performance Schema. To verify successful
initialization, use this statement:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa55566322"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SHOW</span> <span class="token keyword">VARIABLES</span> <span class="token operator">LIKE</span> <span class="token string">'performance_schema'</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> Variable_name <span class="token punctuation">|</span> Value <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> performance_schema <span class="token punctuation">|</span> ON <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span></code></pre>
</div>
<p>
A value of
<code class="literal">
ON
</code>
means that the Performance Schema
initialized successfully and is ready for use. A value of
<code class="literal">
OFF
</code>
means that some error occurred. Check the
server error log for information about what went wrong.
</p>
<p>
The Performance Schema is implemented as a storage engine, so you
can see it listed in the output from the Information Schema
<a class="link" href="information-schema-engines-table.html" title="28.3.13 The INFORMATION_SCHEMA ENGINES Table">
<code class="literal">
ENGINES
</code>
</a>
table or the
<a class="link" href="show-engines.html" title="15.7.7.17 SHOW ENGINES Statement">
<code class="literal">
SHOW ENGINES
</code>
</a>
statement:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa18300789"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token operator">*</span> <span class="token keyword">FROM</span> INFORMATION_SCHEMA<span class="token punctuation">.</span><span class="token keyword">ENGINES</span>
<span class="token keyword">WHERE</span> <span class="token keyword">ENGINE</span><span class="token operator">=</span><span class="token string">'PERFORMANCE_SCHEMA'</span>\G
<span class="token output"><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span> 1. row <span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span>
ENGINE<span class="token punctuation">:</span> PERFORMANCE_SCHEMA
SUPPORT<span class="token punctuation">:</span> YES
COMMENT<span class="token punctuation">:</span> Performance Schema
TRANSACTIONS<span class="token punctuation">:</span> NO
XA<span class="token punctuation">:</span> NO
SAVEPOINTS<span class="token punctuation">:</span> NO
</span>
<span class="token prompt">mysql></span> <span class="token keyword">SHOW</span> <span class="token keyword">ENGINES</span>\G
<span class="token punctuation">.</span><span class="token punctuation">.</span><span class="token punctuation">.</span>
<span class="token keyword">Engine</span>: PERFORMANCE_SCHEMA
Support: YES
<span class="token keyword">Comment</span>: Performance <span class="token keyword">Schema</span>
Transactions: <span class="token keyword">NO</span>
<span class="token keyword">XA</span>: <span class="token keyword">NO</span>
Savepoints: <span class="token keyword">NO</span>
<span class="token punctuation">.</span><span class="token punctuation">.</span><span class="token punctuation">.</span></code></pre>
</div>
<p>
The
<a class="link" href="performance-schema.html" title="Chapter 29 MySQL Performance Schema">
<code class="literal">
PERFORMANCE_SCHEMA
</code>
</a>
storage engine
operates on tables in the
<code class="literal">
performance_schema
</code>
database. You can make
<code class="literal">
performance_schema
</code>
the
default database so that references to its tables need not be
qualified with the database name:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-sql"><div class="docs-select-all right" id="sa39555297"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">USE</span> performance_schema<span class="token punctuation">;</span></code></pre>
</div>
<p>
Performance Schema tables are stored in the
<code class="literal">
performance_schema
</code>
database. Information about
the structure of this database and its tables can be obtained, as
for any other database, by selecting from the
<code class="literal">
INFORMATION_SCHEMA
</code>
database or by using
<a class="link" href="show.html" title="15.7.7 SHOW Statements">
<code class="literal">
SHOW
</code>
</a>
statements. For example, use
either of these statements to see what Performance Schema tables
exist:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa49816337"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token keyword">TABLE_NAME</span> <span class="token keyword">FROM</span> INFORMATION_SCHEMA<span class="token punctuation">.</span><span class="token keyword">TABLES</span>
<span class="token keyword">WHERE</span> TABLE_SCHEMA <span class="token operator">=</span> <span class="token string">'performance_schema'</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> TABLE_NAME <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> accounts <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> cond_instances <span class="token punctuation">|</span></span>
<span class="token punctuation">.</span><span class="token punctuation">.</span><span class="token punctuation">.</span>
<span class="token output"><span class="token punctuation">|</span> events_stages_current <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> events_stages_history <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> events_stages_history_long <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> events_stages_summary_by_account_by_event_name <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> events_stages_summary_by_host_by_event_name <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> events_stages_summary_by_thread_by_event_name <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> events_stages_summary_by_user_by_event_name <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> events_stages_summary_global_by_event_name <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> events_statements_current <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> events_statements_history <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> events_statements_history_long <span class="token punctuation">|</span></span>
<span class="token punctuation">.</span><span class="token punctuation">.</span><span class="token punctuation">.</span>
<span class="token output"><span class="token punctuation">|</span> file_instances <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> file_summary_by_event_name <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> file_summary_by_instance <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> host_cache <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> hosts <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> memory_summary_by_account_by_event_name <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> memory_summary_by_host_by_event_name <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> memory_summary_by_thread_by_event_name <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> memory_summary_by_user_by_event_name <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> memory_summary_global_by_event_name <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> metadata_locks <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> mutex_instances <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> objects_summary_global_by_type <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> performance_timers <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> replication_connection_configuration <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> replication_connection_status <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> replication_applier_configuration <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> replication_applier_status <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> replication_applier_status_by_coordinator <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> replication_applier_status_by_worker <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> rwlock_instances <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> session_account_connect_attrs <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> session_connect_attrs <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> setup_actors <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> setup_consumers <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> setup_instruments <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> setup_objects <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> socket_instances <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> socket_summary_by_event_name <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> socket_summary_by_instance <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> table_handles <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> table_io_waits_summary_by_index_usage <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> table_io_waits_summary_by_table <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> table_lock_waits_summary_by_table <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> threads <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> users <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token prompt">mysql></span> <span class="token keyword">SHOW</span> <span class="token keyword">TABLES</span> <span class="token keyword">FROM</span> performance_schema<span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> Tables_in_performance_schema <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> accounts <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> cond_instances <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> events_stages_current <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> events_stages_history <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> events_stages_history_long <span class="token punctuation">|</span></span>
<span class="token punctuation">.</span><span class="token punctuation">.</span><span class="token punctuation">.</span></code></pre>
</div>
<p>
The number of Performance Schema tables increases over time as
implementation of additional instrumentation proceeds.
</p>
<p>
The name of the
<code class="literal">
performance_schema
</code>
database is
lowercase, as are the names of tables within it. Queries should
specify the names in lowercase.
</p>
<p>
To see the structure of individual tables, use
<a class="link" href="show-create-table.html" title="15.7.7.11 SHOW CREATE TABLE Statement">
<code class="literal">
SHOW CREATE TABLE
</code>
</a>
:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa74388023"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SHOW</span> <span class="token keyword">CREATE</span> <span class="token keyword">TABLE</span> performance_schema<span class="token punctuation">.</span>setup_consumers\G
<span class="token output"><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span> 1. row <span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span>
Table<span class="token punctuation">:</span> setup_consumers
Create Table<span class="token punctuation">:</span> CREATE TABLE `setup_consumers` (
`NAME` varchar(64) NOT NULL,
`ENABLED` enum('YES','NO') NOT NULL,
PRIMARY KEY (`NAME`)
) ENGINE=PERFORMANCE_SCHEMA DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci</span></code></pre>
</div>
<p>
Table structure is also available by selecting from tables such as
<a class="link" href="information-schema-columns-table.html" title="28.3.8 The INFORMATION_SCHEMA COLUMNS Table">
<code class="literal">
INFORMATION_SCHEMA.COLUMNS
</code>
</a>
or by
using statements such as
<a class="link" href="show-columns.html" title="15.7.7.6 SHOW COLUMNS Statement">
<code class="literal">
SHOW
COLUMNS
</code>
</a>
.
</p>
<p>
Tables in the
<code class="literal">
performance_schema
</code>
database can
be grouped according to the type of information in them: Current
events, event histories and summaries, object instances, and setup
(configuration) information. The following examples illustrate a
few uses for these tables. For detailed information about the
tables in each group, see
<a class="xref" href="performance-schema-table-descriptions.html" title="29.12 Performance Schema Table Descriptions">
Section 29.12, “Performance Schema Table Descriptions”
</a>
.
</p>
<p>
Initially, not all instruments and consumers are enabled, so the
performance schema does not collect all events. To turn all of
these on and enable event timing, execute two statements (the row
counts may differ depending on MySQL version):
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa10527538"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">UPDATE</span> performance_schema<span class="token punctuation">.</span>setup_instruments
<span class="token keyword">SET</span> ENABLED <span class="token operator">=</span> <span class="token string">'YES'</span><span class="token punctuation">,</span> TIMED <span class="token operator">=</span> <span class="token string">'YES'</span><span class="token punctuation">;</span>
<span class="token output">Query OK, 560 rows affected (0.04 sec)</span>
<span class="token prompt">mysql></span> <span class="token keyword">UPDATE</span> performance_schema<span class="token punctuation">.</span>setup_consumers
<span class="token keyword">SET</span> ENABLED <span class="token operator">=</span> <span class="token string">'YES'</span><span class="token punctuation">;</span>
<span class="token output">Query OK, 10 rows affected (0.00 sec)</span></code></pre>
</div>
<p>
To see what the server is doing at the moment, examine the
<a class="link" href="performance-schema-events-waits-current-table.html" title="29.12.4.1 The events_waits_current Table">
<code class="literal">
events_waits_current
</code>
</a>
table. It
contains one row per thread showing each thread's most recent
monitored event:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa92565743"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token operator">*</span>
<span class="token keyword">FROM</span> performance_schema<span class="token punctuation">.</span>events_waits_current\G
<span class="token output"><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span> 1. row <span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span>
THREAD_ID<span class="token punctuation">:</span> 0
EVENT_ID<span class="token punctuation">:</span> 5523
END_EVENT_ID<span class="token punctuation">:</span> 5523
EVENT_NAME<span class="token punctuation">:</span> wait/synch/mutex/mysys/THR_LOCK<span class="token punctuation">:</span><span class="token punctuation">:</span>mutex
SOURCE<span class="token punctuation">:</span> thr_lock.c<span class="token punctuation">:</span>525
TIMER_START<span class="token punctuation">:</span> 201660494489586
TIMER_END<span class="token punctuation">:</span> 201660494576112
TIMER_WAIT<span class="token punctuation">:</span> 86526
SPINS<span class="token punctuation">:</span> NULL
OBJECT_SCHEMA<span class="token punctuation">:</span> NULL
OBJECT_NAME<span class="token punctuation">:</span> NULL
INDEX_NAME<span class="token punctuation">:</span> NULL
OBJECT_TYPE<span class="token punctuation">:</span> NULL
OBJECT_INSTANCE_BEGIN<span class="token punctuation">:</span> 142270668
NESTING_EVENT_ID<span class="token punctuation">:</span> NULL
NESTING_EVENT_TYPE<span class="token punctuation">:</span> NULL
OPERATION<span class="token punctuation">:</span> lock
NUMBER_OF_BYTES<span class="token punctuation">:</span> NULL
FLAGS<span class="token punctuation">:</span> 0
...</span></code></pre>
</div>
<p>
This event indicates that thread 0 was waiting for 86,526
picoseconds to acquire a lock on
<code class="literal">
THR_LOCK::mutex
</code>
, a mutex in the
<code class="literal">
mysys
</code>
subsystem. The first few columns provide
the following information:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
The ID columns indicate which thread the event comes from and
the event number.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
EVENT_NAME
</code>
indicates what was instrumented
and
<code class="literal">
SOURCE
</code>
indicates which source file
contains the instrumented code.
</p>
</li>
<li class="listitem">
<p>
The timer columns show when the event started and stopped and
how long it took. If an event is still in progress, the
<code class="literal">
TIMER_END
</code>
and
<code class="literal">
TIMER_WAIT
</code>
values are
<code class="literal">
NULL
</code>
. Timer values are
approximate and expressed in picoseconds. For information
about timers and event time collection, see
<a class="xref" href="performance-schema-timing.html" title="29.4.1 Performance Schema Event Timing">
Section 29.4.1, “Performance Schema Event Timing”
</a>
.
</p>
</li>
</ul>
</div>
<p>
The history tables contain the same kind of rows as the
current-events table but have more rows and show what the server
has been doing
<span class="quote">
“
<span class="quote">
recently
</span>
”
</span>
rather than
<span class="quote">
“
<span class="quote">
currently.
</span>
”
</span>
The
<a class="link" href="performance-schema-events-waits-history-table.html" title="29.12.4.2 The events_waits_history Table">
<code class="literal">
events_waits_history
</code>
</a>
and
<a class="link" href="performance-schema-events-waits-history-long-table.html" title="29.12.4.3 The events_waits_history_long Table">
<code class="literal">
events_waits_history_long
</code>
</a>
tables
contain the most recent 10 events per thread and most recent
10,000 events, respectively. For example, to see information for
recent events produced by thread 13, do this:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa7034706"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> EVENT_ID<span class="token punctuation">,</span> EVENT_NAME<span class="token punctuation">,</span> TIMER_WAIT
<span class="token keyword">FROM</span> performance_schema<span class="token punctuation">.</span>events_waits_history
<span class="token keyword">WHERE</span> THREAD_ID <span class="token operator">=</span> <span class="token number">13</span>
<span class="token keyword">ORDER</span> <span class="token keyword">BY</span> EVENT_ID<span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> EVENT_ID <span class="token punctuation">|</span> EVENT_NAME <span class="token punctuation">|</span> TIMER_WAIT <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> 86 <span class="token punctuation">|</span> wait/synch/mutex/mysys/THR_LOCK::mutex <span class="token punctuation">|</span> 686322 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> 87 <span class="token punctuation">|</span> wait/synch/mutex/mysys/THR_LOCK_malloc <span class="token punctuation">|</span> 320535 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> 88 <span class="token punctuation">|</span> wait/synch/mutex/mysys/THR_LOCK_malloc <span class="token punctuation">|</span> 339390 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> 89 <span class="token punctuation">|</span> wait/synch/mutex/mysys/THR_LOCK_malloc <span class="token punctuation">|</span> 377100 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> 90 <span class="token punctuation">|</span> wait/synch/mutex/sql/LOCK_plugin <span class="token punctuation">|</span> 614673 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> 91 <span class="token punctuation">|</span> wait/synch/mutex/sql/LOCK_open <span class="token punctuation">|</span> 659925 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> 92 <span class="token punctuation">|</span> wait/synch/mutex/sql/THD::LOCK_thd_data <span class="token punctuation">|</span> 494001 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> 93 <span class="token punctuation">|</span> wait/synch/mutex/mysys/THR_LOCK_malloc <span class="token punctuation">|</span> 222489 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> 94 <span class="token punctuation">|</span> wait/synch/mutex/mysys/THR_LOCK_malloc <span class="token punctuation">|</span> 214947 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> 95 <span class="token punctuation">|</span> wait/synch/mutex/mysys/LOCK_alarm <span class="token punctuation">|</span> 312993 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span></code></pre>
</div>
<p>
As new events are added to a history table, older events are
discarded if the table is full.
</p>
<p>
Summary tables provide aggregated information for all events over
time. The tables in this group summarize event data in different
ways. To see which instruments have been executed the most times
or have taken the most wait time, sort the
<a class="link" href="performance-schema-wait-summary-tables.html" title="29.12.20.1 Wait Event Summary Tables">
<code class="literal">
events_waits_summary_global_by_event_name
</code>
</a>
table on the
<code class="literal">
COUNT_STAR
</code>
or
<code class="literal">
SUM_TIMER_WAIT
</code>
column, which correspond to a
<code class="literal">
COUNT(*)
</code>
or
<code class="literal">
SUM(TIMER_WAIT)
</code>
value, respectively, calculated over all events:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa99944842"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> EVENT_NAME<span class="token punctuation">,</span> COUNT_STAR
<span class="token keyword">FROM</span> performance_schema<span class="token punctuation">.</span>events_waits_summary_global_by_event_name
<span class="token keyword">ORDER</span> <span class="token keyword">BY</span> COUNT_STAR <span class="token keyword">DESC</span> <span class="token keyword">LIMIT</span> <span class="token number">10</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> EVENT_NAME <span class="token punctuation">|</span> COUNT_STAR <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> wait/synch/mutex/mysys/THR_LOCK_malloc <span class="token punctuation">|</span> 6419 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> wait/io/file/sql/FRM <span class="token punctuation">|</span> 452 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> wait/synch/mutex/sql/LOCK_plugin <span class="token punctuation">|</span> 337 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> wait/synch/mutex/mysys/THR_LOCK_open <span class="token punctuation">|</span> 187 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> wait/synch/mutex/mysys/LOCK_alarm <span class="token punctuation">|</span> 147 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> wait/synch/mutex/sql/THD::LOCK_thd_data <span class="token punctuation">|</span> 115 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> wait/io/file/myisam/kfile <span class="token punctuation">|</span> 102 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> wait/synch/mutex/sql/LOCK_global_system_variables <span class="token punctuation">|</span> 89 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> wait/synch/mutex/mysys/THR_LOCK::mutex <span class="token punctuation">|</span> 89 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> wait/synch/mutex/sql/LOCK_open <span class="token punctuation">|</span> 88 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> EVENT_NAME<span class="token punctuation">,</span> SUM_TIMER_WAIT
<span class="token keyword">FROM</span> performance_schema<span class="token punctuation">.</span>events_waits_summary_global_by_event_name
<span class="token keyword">ORDER</span> <span class="token keyword">BY</span> SUM_TIMER_WAIT <span class="token keyword">DESC</span> <span class="token keyword">LIMIT</span> <span class="token number">10</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> EVENT_NAME <span class="token punctuation">|</span> SUM_TIMER_WAIT <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> wait/io/file/sql/MYSQL_LOG <span class="token punctuation">|</span> 1599816582 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> wait/synch/mutex/mysys/THR_LOCK_malloc <span class="token punctuation">|</span> 1530083250 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> wait/io/file/sql/binlog_index <span class="token punctuation">|</span> 1385291934 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> wait/io/file/sql/FRM <span class="token punctuation">|</span> 1292823243 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> wait/io/file/myisam/kfile <span class="token punctuation">|</span> 411193611 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> wait/io/file/myisam/dfile <span class="token punctuation">|</span> 322401645 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> wait/synch/mutex/mysys/LOCK_alarm <span class="token punctuation">|</span> 145126935 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> wait/io/file/sql/casetest <span class="token punctuation">|</span> 104324715 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> wait/synch/mutex/sql/LOCK_plugin <span class="token punctuation">|</span> 86027823 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> wait/io/file/sql/pid <span class="token punctuation">|</span> 72591750 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span></code></pre>
</div>
<p>
These results show that the
<code class="literal">
THR_LOCK_malloc
</code>
mutex is
<span class="quote">
“
<span class="quote">
hot,
</span>
”
</span>
both in terms of how often it is used
and amount of time that threads wait attempting to acquire it.
</p>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Note
</div>
<p>
The
<code class="literal">
THR_LOCK_malloc
</code>
mutex is used only in
debug builds. In production builds it is not hot because it is
nonexistent.
</p>
</div>
<p>
Instance tables document what types of objects are instrumented.
An instrumented object, when used by the server, produces an
event. These tables provide event names and explanatory notes or
status information. For example, the
<a class="link" href="performance-schema-file-instances-table.html" title="29.12.3.2 The file_instances Table">
<code class="literal">
file_instances
</code>
</a>
table lists instances
of instruments for file I/O operations and their associated files:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa7409478"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token operator">*</span>
<span class="token keyword">FROM</span> performance_schema<span class="token punctuation">.</span>file_instances\G
<span class="token output"><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span> 1. row <span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span>
FILE_NAME<span class="token punctuation">:</span> /opt/mysql-log/60500/binlog.000007
EVENT_NAME<span class="token punctuation">:</span> wait/io/file/sql/binlog
OPEN_COUNT<span class="token punctuation">:</span> 0
<span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span> 2. row <span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span>
FILE_NAME<span class="token punctuation">:</span> /opt/mysql/60500/data/mysql/tables_priv.MYI
EVENT_NAME<span class="token punctuation">:</span> wait/io/file/myisam/kfile
OPEN_COUNT<span class="token punctuation">:</span> 1
<span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span> 3. row <span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span>
FILE_NAME<span class="token punctuation">:</span> /opt/mysql/60500/data/mysql/columns_priv.MYI
EVENT_NAME<span class="token punctuation">:</span> wait/io/file/myisam/kfile
OPEN_COUNT<span class="token punctuation">:</span> 1
...</span></code></pre>
</div>
<p>
Setup tables are used to configure and display monitoring
characteristics. For example,
<a class="link" href="performance-schema-setup-instruments-table.html" title="29.12.2.3 The setup_instruments Table">
<code class="literal">
setup_instruments
</code>
</a>
lists the set of
instruments for which events can be collected and shows which of
them are enabled:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa8199930"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token keyword">NAME</span><span class="token punctuation">,</span> ENABLED<span class="token punctuation">,</span> TIMED
<span class="token keyword">FROM</span> performance_schema<span class="token punctuation">.</span>setup_instruments<span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> NAME <span class="token punctuation">|</span> ENABLED <span class="token punctuation">|</span> TIMED <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token punctuation">.</span><span class="token punctuation">.</span><span class="token punctuation">.</span>
<span class="token output"><span class="token punctuation">|</span> stage/sql/end <span class="token punctuation">|</span> NO <span class="token punctuation">|</span> NO <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> stage/sql/executing <span class="token punctuation">|</span> NO <span class="token punctuation">|</span> NO <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> stage/sql/init <span class="token punctuation">|</span> NO <span class="token punctuation">|</span> NO <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> stage/sql/insert <span class="token punctuation">|</span> NO <span class="token punctuation">|</span> NO <span class="token punctuation">|</span></span>
<span class="token punctuation">.</span><span class="token punctuation">.</span><span class="token punctuation">.</span>
<span class="token output"><span class="token punctuation">|</span> statement/sql/load <span class="token punctuation">|</span> YES <span class="token punctuation">|</span> YES <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> statement/sql/grant <span class="token punctuation">|</span> YES <span class="token punctuation">|</span> YES <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> statement/sql/check <span class="token punctuation">|</span> YES <span class="token punctuation">|</span> YES <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> statement/sql/flush <span class="token punctuation">|</span> YES <span class="token punctuation">|</span> YES <span class="token punctuation">|</span></span>
<span class="token punctuation">.</span><span class="token punctuation">.</span><span class="token punctuation">.</span>
<span class="token output"><span class="token punctuation">|</span> wait/synch/mutex/sql/LOCK_global_read_lock <span class="token punctuation">|</span> YES <span class="token punctuation">|</span> YES <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> wait/synch/mutex/sql/LOCK_global_system_variables <span class="token punctuation">|</span> YES <span class="token punctuation">|</span> YES <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> wait/synch/mutex/sql/LOCK_lock_db <span class="token punctuation">|</span> YES <span class="token punctuation">|</span> YES <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> wait/synch/mutex/sql/LOCK_manager <span class="token punctuation">|</span> YES <span class="token punctuation">|</span> YES <span class="token punctuation">|</span></span>
<span class="token punctuation">.</span><span class="token punctuation">.</span><span class="token punctuation">.</span>
<span class="token output"><span class="token punctuation">|</span> wait/synch/rwlock/sql/LOCK_grant <span class="token punctuation">|</span> YES <span class="token punctuation">|</span> YES <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> wait/synch/rwlock/sql/LOGGER::LOCK_logger <span class="token punctuation">|</span> YES <span class="token punctuation">|</span> YES <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> wait/synch/rwlock/sql/LOCK_sys_init_connect <span class="token punctuation">|</span> YES <span class="token punctuation">|</span> YES <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> wait/synch/rwlock/sql/LOCK_sys_init_slave <span class="token punctuation">|</span> YES <span class="token punctuation">|</span> YES <span class="token punctuation">|</span></span>
<span class="token punctuation">.</span><span class="token punctuation">.</span><span class="token punctuation">.</span>
<span class="token output"><span class="token punctuation">|</span> wait/io/file/sql/binlog <span class="token punctuation">|</span> YES <span class="token punctuation">|</span> YES <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> wait/io/file/sql/binlog_index <span class="token punctuation">|</span> YES <span class="token punctuation">|</span> YES <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> wait/io/file/sql/casetest <span class="token punctuation">|</span> YES <span class="token punctuation">|</span> YES <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> wait/io/file/sql/dbopt <span class="token punctuation">|</span> YES <span class="token punctuation">|</span> YES <span class="token punctuation">|</span></span>
<span class="token punctuation">.</span><span class="token punctuation">.</span><span class="token punctuation">.</span></code></pre>
</div>
<p>
To understand how to interpret instrument names, see
<a class="xref" href="performance-schema-instrument-naming.html" title="29.6 Performance Schema Instrument Naming Conventions">
Section 29.6, “Performance Schema Instrument Naming Conventions”
</a>
.
</p>
<p>
To control whether events are collected for an instrument, set its
<code class="literal">
ENABLED
</code>
value to
<code class="literal">
YES
</code>
or
<code class="literal">
NO
</code>
. For example:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa47457320"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">UPDATE</span> performance_schema<span class="token punctuation">.</span>setup_instruments
<span class="token keyword">SET</span> ENABLED <span class="token operator">=</span> <span class="token string">'NO'</span>
<span class="token keyword">WHERE</span> <span class="token keyword">NAME</span> <span class="token operator">=</span> <span class="token string">'wait/synch/mutex/sql/LOCK_mysql_create_db'</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
The Performance Schema uses collected events to update tables in
the
<code class="literal">
performance_schema
</code>
database, which act as
<span class="quote">
“
<span class="quote">
consumers
</span>
”
</span>
of event information. The
<a class="link" href="performance-schema-setup-consumers-table.html" title="29.12.2.2 The setup_consumers Table">
<code class="literal">
setup_consumers
</code>
</a>
table lists the
available consumers and which are enabled:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa34964743"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token operator">*</span> <span class="token keyword">FROM</span> performance_schema<span class="token punctuation">.</span>setup_consumers<span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> NAME <span class="token punctuation">|</span> ENABLED <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> events_stages_current <span class="token punctuation">|</span> NO <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> events_stages_history <span class="token punctuation">|</span> NO <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> events_stages_history_long <span class="token punctuation">|</span> NO <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> events_statements_cpu <span class="token punctuation">|</span> NO <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> events_statements_current <span class="token punctuation">|</span> YES <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> events_statements_history <span class="token punctuation">|</span> YES <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> events_statements_history_long <span class="token punctuation">|</span> NO <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> events_transactions_current <span class="token punctuation">|</span> YES <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> events_transactions_history <span class="token punctuation">|</span> YES <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> events_transactions_history_long <span class="token punctuation">|</span> NO <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> events_waits_current <span class="token punctuation">|</span> NO <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> events_waits_history <span class="token punctuation">|</span> NO <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> events_waits_history_long <span class="token punctuation">|</span> NO <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> global_instrumentation <span class="token punctuation">|</span> YES <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> thread_instrumentation <span class="token punctuation">|</span> YES <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> statements_digest <span class="token punctuation">|</span> YES <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span></code></pre>
</div>
<p>
To control whether the Performance Schema maintains a consumer as
a destination for event information, set its
<code class="literal">
ENABLED
</code>
value.
</p>
<p>
For more information about the setup tables and how to use them to
control event collection, see
<a class="xref" href="performance-schema-filtering.html" title="29.4.2 Performance Schema Event Filtering">
Section 29.4.2, “Performance Schema Event Filtering”
</a>
.
</p>
<p>
There are some miscellaneous tables that do not fall into any of
the previous groups. For example,
<a class="link" href="performance-schema-performance-timers-table.html" title="29.12.22.6 The performance_timers Table">
<code class="literal">
performance_timers
</code>
</a>
lists the
available event timers and their characteristics. For information
about timers, see
<a class="xref" href="performance-schema-timing.html" title="29.4.1 Performance Schema Event Timing">
Section 29.4.1, “Performance Schema Event Timing”
</a>
.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/apis-tcl.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h2 class="title">
<a name="apis-tcl">
</a>
31.12 MySQL Tcl API
</h2>
</div>
</div>
</div>
<a class="indexterm" name="idm46045060283504">
</a>
<p>
<code class="literal">
MySQLtcl
</code>
is a simple API for accessing a MySQL
database server from the
<a class="ulink" href="http://en.wikipedia.org/wiki/Tcl" target="_blank">
Tcl programming
language
</a>
. It can be found at
<a class="ulink" href="http://www.xdobry.de/mysqltcl/" target="_blank">
http://www.xdobry.de/mysqltcl/
</a>
.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/creating-rsa-files-using-openssl.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="creating-rsa-files-using-openssl">
</a>
8.3.3.3 Creating RSA Keys Using openssl
</h4>
</div>
</div>
</div>
<p>
This section describes how to use the
<span class="command">
<strong>
openssl
</strong>
</span>
command to set up the RSA key files that enable MySQL to support
secure password exchange over unencrypted connections for
accounts authenticated by the
<code class="literal">
sha256_password
</code>
(deprecated) and
<code class="literal">
caching_sha2_password
</code>
plugins.
</p>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Note
</div>
<p>
An easier alternative to generating the files required for SSL
than the procedure described here is to let the server
autogenerate them; see
<a class="xref" href="creating-ssl-rsa-files-using-mysql.html" title="8.3.3.1 Creating SSL and RSA Certificates and Keys using MySQL">
Section 8.3.3.1, “Creating SSL and RSA Certificates and Keys using MySQL”
</a>
.
</p>
</div>
<p>
To create the RSA private and public key-pair files, run these
commands while logged into the system account used to run the
MySQL server so that the files are owned by that account:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-terminal"><div class="docs-select-all right" id="sa31773720"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal">openssl genrsa <span class="token property">-out</span> private_key<span class="token punctuation">.</span>pem 2048
openssl rsa <span class="token property">-in</span> private_key<span class="token punctuation">.</span>pem <span class="token property">-pubout</span> <span class="token property">-out</span> public_key<span class="token punctuation">.</span>pem</code></pre>
</div>
<p>
Those commands create 2,048-bit keys. To create stronger keys,
use a larger value.
</p>
<p>
Then set the access modes for the key files. The private key
should be readable only by the server, whereas the public key
can be freely distributed to client users:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-terminal"><div class="docs-select-all right" id="sa80683155"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal">chmod 400 private_key<span class="token punctuation">.</span>pem
chmod 444 public_key<span class="token punctuation">.</span>pem</code></pre>
</div>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/charset-we-sets.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="charset-we-sets">
</a>
12.10.2 West European Character Sets
</h3>
</div>
</div>
</div>
<a class="indexterm" name="idm46045216012880">
</a>
<a class="indexterm" name="idm46045216011424">
</a>
<p>
Western European character sets cover most West European
languages, such as French, Spanish, Catalan, Basque, Portuguese,
Italian, Albanian, Dutch, German, Danish, Swedish, Norwegian,
Finnish, Faroese, Icelandic, Irish, Scottish, and English.
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<code class="literal">
ascii
</code>
(US ASCII) collations:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
<code class="literal">
ascii_bin
</code>
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
ascii_general_ci
</code>
(default)
</p>
</li>
</ul>
</div>
</li>
<li class="listitem">
<p>
<code class="literal">
cp850
</code>
(DOS West European) collations:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
<code class="literal">
cp850_bin
</code>
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
cp850_general_ci
</code>
(default)
</p>
</li>
</ul>
</div>
</li>
<li class="listitem">
<p>
<code class="literal">
dec8
</code>
(DEC Western European) collations:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
<code class="literal">
dec8_bin
</code>
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
dec8_swedish_ci
</code>
(default)
</p>
</li>
</ul>
</div>
<p>
The
<code class="literal">
dec
</code>
character set is deprecated;
expect support for it to be removed in a subsequent MySQL
release.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
hp8
</code>
(HP Western European) collations:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
<code class="literal">
hp8_bin
</code>
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
hp8_english_ci
</code>
(default)
</p>
</li>
</ul>
</div>
<p>
The
<code class="literal">
hp8
</code>
character set is deprecated;
expect support for it to be removed in a subsequent MySQL
release.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
latin1
</code>
(cp1252 West European) collations:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
<code class="literal">
latin1_bin
</code>
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
latin1_danish_ci
</code>
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
latin1_general_ci
</code>
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
latin1_general_cs
</code>
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
latin1_german1_ci
</code>
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
latin1_german2_ci
</code>
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
latin1_spanish_ci
</code>
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
latin1_swedish_ci
</code>
(default)
</p>
</li>
</ul>
</div>
<p>
MySQL's
<code class="literal">
latin1
</code>
is the same as the Windows
<code class="literal">
cp1252
</code>
character set. This means it is
the same as the official
<code class="literal">
ISO 8859-1
</code>
or
IANA (Internet Assigned Numbers Authority)
<code class="literal">
latin1
</code>
, except that IANA
<code class="literal">
latin1
</code>
treats the code points between
<code class="literal">
0x80
</code>
and
<code class="literal">
0x9f
</code>
as
<span class="quote">
“
<span class="quote">
undefined,
</span>
”
</span>
whereas
<code class="literal">
cp1252
</code>
,
and therefore MySQL's
<code class="literal">
latin1
</code>
, assign
characters for those positions. For example,
<code class="literal">
0x80
</code>
is the Euro sign. For the
<span class="quote">
“
<span class="quote">
undefined
</span>
”
</span>
entries in
<code class="literal">
cp1252
</code>
, MySQL translates
<code class="literal">
0x81
</code>
to Unicode
<code class="literal">
0x0081
</code>
,
<code class="literal">
0x8d
</code>
to
<code class="literal">
0x008d
</code>
,
<code class="literal">
0x8f
</code>
to
<code class="literal">
0x008f
</code>
,
<code class="literal">
0x90
</code>
to
<code class="literal">
0x0090
</code>
, and
<code class="literal">
0x9d
</code>
to
<code class="literal">
0x009d
</code>
.
</p>
<p>
The
<code class="literal">
latin1_swedish_ci
</code>
collation is the
default that probably is used by the majority of MySQL
customers. Although it is frequently said that it is based
on the Swedish/Finnish collation rules, there are Swedes and
Finns who disagree with this statement.
</p>
<a class="indexterm" name="idm46045215955568">
</a>
<a class="indexterm" name="idm46045215954480">
</a>
<a class="indexterm" name="idm46045215953392">
</a>
<a class="indexterm" name="idm46045215952304">
</a>
<p>
The
<code class="literal">
latin1_german1_ci
</code>
and
<code class="literal">
latin1_german2_ci
</code>
collations are based on
the DIN-1 and DIN-2 standards, where DIN stands for
<span class="emphasis">
<em>
<span class="phrase" lang="de">
Deutsches Institut für
Normung
</span>
</em>
</span>
(the German equivalent of ANSI).
DIN-1 is called the
<span class="quote">
“
<span class="quote">
dictionary collation
</span>
”
</span>
and
DIN-2 is called the
<span class="quote">
“
<span class="quote">
phone book collation.
</span>
”
</span>
For
an example of the effect this has in comparisons or when
doing searches, see
<a class="xref" href="charset-collation-effect.html" title="12.8.6 Examples of the Effect of Collation">
Section 12.8.6, “Examples of the Effect of Collation”
</a>
.
</p>
<a class="indexterm" name="idm46045215946544">
</a>
<a class="indexterm" name="idm46045215945504">
</a>
<a class="indexterm" name="idm46045215944416">
</a>
<a class="indexterm" name="idm46045215943328">
</a>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
<code class="literal">
latin1_german1_ci
</code>
(dictionary) rules:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-none"><div class="docs-select-all right" id="sa99218899"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-none">Ä = A
Ö = O
Ü = U
ß = s</code></pre>
</div>
</li>
<li class="listitem">
<p>
<code class="literal">
latin1_german2_ci
</code>
(phone-book) rules:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-none"><div class="docs-select-all right" id="sa51125056"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-none">Ä = AE
Ö = OE
Ü = UE
ß = ss</code></pre>
</div>
</li>
</ul>
</div>
<p>
In the
<code class="literal">
latin1_spanish_ci
</code>
collation,
<code class="literal">
ñ
</code>
(n-tilde) is a separate letter between
<code class="literal">
n
</code>
and
<code class="literal">
o
</code>
.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
macroman
</code>
(Mac West European) collations:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
<code class="literal">
macroman_bin
</code>
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
macroman_general_ci
</code>
(default)
</p>
</li>
</ul>
</div>
<p>
<code class="literal">
macroroman
</code>
is deprecated; expect support
for it to be removed in a subsequent MySQL release.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
swe7
</code>
(7bit Swedish) collations:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
<code class="literal">
swe7_bin
</code>
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
swe7_swedish_ci
</code>
(default)
</p>
</li>
</ul>
</div>
</li>
</ul>
</div>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/upgrade-docker-mysql.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h2 class="title">
<a name="upgrade-docker-mysql">
</a>
3.12 Upgrading a Docker Installation of MySQL
</h2>
</div>
</div>
</div>
<a class="indexterm" name="idm46045325890464">
</a>
<a class="indexterm" name="idm46045325889424">
</a>
<p>
To upgrade a Docker installation of MySQL, refer to
<a class="xref" href="docker-mysql-getting-started.html#docker-upgrading" title="Upgrading a MySQL Server Container">
Upgrading a MySQL Server Container
</a>
.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/information-schema-innodb-trx-table.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="information-schema-innodb-trx-table">
</a>
28.4.28 The INFORMATION_SCHEMA INNODB_TRX Table
</h3>
</div>
</div>
</div>
<a class="indexterm" name="idm46045076250352">
</a>
<p>
The
<a class="link" href="information-schema-innodb-trx-table.html" title="28.4.28 The INFORMATION_SCHEMA INNODB_TRX Table">
<code class="literal">
INNODB_TRX
</code>
</a>
table provides
information about every transaction currently executing inside
<code class="literal">
InnoDB
</code>
, including whether the transaction is
waiting for a lock, when the transaction started, and the SQL
statement the transaction is executing, if any.
</p>
<p>
For usage information, see
<a class="xref" href="innodb-information-schema-examples.html" title="17.15.2.1 Using InnoDB Transaction and Locking Information">
Section 17.15.2.1, “Using InnoDB Transaction and Locking Information”
</a>
.
</p>
<p>
The
<a class="link" href="information-schema-innodb-trx-table.html" title="28.4.28 The INFORMATION_SCHEMA INNODB_TRX Table">
<code class="literal">
INNODB_TRX
</code>
</a>
table has these
columns:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<code class="literal">
TRX_ID
</code>
</p>
<p>
A unique transaction ID number, internal to
<code class="literal">
InnoDB
</code>
. These IDs are not created for
transactions that are read only and nonlocking. For details,
see
<a class="xref" href="innodb-performance-ro-txn.html" title="10.5.3 Optimizing InnoDB Read-Only Transactions">
Section 10.5.3, “Optimizing InnoDB Read-Only Transactions”
</a>
.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
TRX_WEIGHT
</code>
</p>
<p>
The weight of a transaction, reflecting (but not necessarily
the exact count of) the number of rows altered and the number
of rows locked by the transaction. To resolve a deadlock,
<code class="literal">
InnoDB
</code>
selects the transaction with the
smallest weight as the
<span class="quote">
“
<span class="quote">
victim
</span>
”
</span>
to roll back.
Transactions that have changed nontransactional tables are
considered heavier than others, regardless of the number of
altered and locked rows.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
TRX_STATE
</code>
</p>
<p>
The transaction execution state. Permitted values are
<code class="literal">
RUNNING
</code>
,
<code class="literal">
LOCK WAIT
</code>
,
<code class="literal">
ROLLING BACK
</code>
, and
<code class="literal">
COMMITTING
</code>
.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
TRX_STARTED
</code>
</p>
<p>
The transaction start time.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
TRX_REQUESTED_LOCK_ID
</code>
</p>
<p>
The ID of the lock the transaction is currently waiting for,
if
<code class="literal">
TRX_STATE
</code>
is
<code class="literal">
LOCK
WAIT
</code>
; otherwise
<code class="literal">
NULL
</code>
. To obtain
details about the lock, join this column with the
<code class="literal">
ENGINE_LOCK_ID
</code>
column of the Performance
Schema
<a class="link" href="performance-schema-data-locks-table.html" title="29.12.13.1 The data_locks Table">
<code class="literal">
data_locks
</code>
</a>
table.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
TRX_WAIT_STARTED
</code>
</p>
<p>
The time when the transaction started waiting on the lock, if
<code class="literal">
TRX_STATE
</code>
is
<code class="literal">
LOCK WAIT
</code>
;
otherwise
<code class="literal">
NULL
</code>
.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
TRX_MYSQL_THREAD_ID
</code>
</p>
<p>
The MySQL thread ID. To obtain details about the thread, join
this column with the
<code class="literal">
ID
</code>
column of the
<code class="literal">
INFORMATION_SCHEMA
</code>
<a class="link" href="information-schema-processlist-table.html" title="28.3.23 The INFORMATION_SCHEMA PROCESSLIST Table">
<code class="literal">
PROCESSLIST
</code>
</a>
table, but see
<a class="xref" href="innodb-information-schema-internal-data.html" title="17.15.2.3 Persistence and Consistency of InnoDB Transaction and Locking Information">
Section 17.15.2.3, “Persistence and Consistency of InnoDB Transaction and Locking
Information”
</a>
.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
TRX_QUERY
</code>
</p>
<p>
The SQL statement that is being executed by the transaction.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
TRX_OPERATION_STATE
</code>
</p>
<p>
The transaction's current operation, if any; otherwise
<code class="literal">
NULL
</code>
.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
TRX_TABLES_IN_USE
</code>
</p>
<p>
The number of
<code class="literal">
InnoDB
</code>
tables used while
processing the current SQL statement of this transaction.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
TRX_TABLES_LOCKED
</code>
</p>
<p>
The number of
<code class="literal">
InnoDB
</code>
tables that the
current SQL statement has row locks on. (Because these are row
locks, not table locks, the tables can usually still be read
from and written to by multiple transactions, despite some
rows being locked.)
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
TRX_LOCK_STRUCTS
</code>
</p>
<p>
The number of locks reserved by the transaction.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
TRX_LOCK_MEMORY_BYTES
</code>
</p>
<p>
The total size taken up by the lock structures of this
transaction in memory.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
TRX_ROWS_LOCKED
</code>
</p>
<p>
The approximate number or rows locked by this transaction. The
value might include delete-marked rows that are physically
present but not visible to the transaction.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
TRX_ROWS_MODIFIED
</code>
</p>
<p>
The number of modified and inserted rows in this transaction.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
TRX_CONCURRENCY_TICKETS
</code>
</p>
<p>
A value indicating how much work the current transaction can
do before being swapped out, as specified by the
<a class="link" href="innodb-parameters.html#sysvar_innodb_concurrency_tickets">
<code class="literal">
innodb_concurrency_tickets
</code>
</a>
system variable.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
TRX_ISOLATION_LEVEL
</code>
</p>
<p>
The isolation level of the current transaction.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
TRX_UNIQUE_CHECKS
</code>
</p>
<p>
Whether unique checks are turned on or off for the current
transaction. For example, they might be turned off during a
bulk data load.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
TRX_FOREIGN_KEY_CHECKS
</code>
</p>
<p>
Whether foreign key checks are turned on or off for the
current transaction. For example, they might be turned off
during a bulk data load.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
TRX_LAST_FOREIGN_KEY_ERROR
</code>
</p>
<p>
The detailed error message for the last foreign key error, if
any; otherwise
<code class="literal">
NULL
</code>
.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
TRX_ADAPTIVE_HASH_LATCHED
</code>
</p>
<p>
Whether the adaptive hash index is locked by the current
transaction. When the adaptive hash index search system is
partitioned, a single transaction does not lock the entire
adaptive hash index. Adaptive hash index partitioning is
controlled by
<a class="link" href="innodb-parameters.html#sysvar_innodb_adaptive_hash_index_parts">
<code class="literal">
innodb_adaptive_hash_index_parts
</code>
</a>
,
which is set to 8 by default.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
TRX_ADAPTIVE_HASH_TIMEOUT
</code>
</p>
<p>
Deprecated in MySQL 5.7.8. Always returns 0.
</p>
<p>
Whether to relinquish the search latch immediately for the
adaptive hash index, or reserve it across calls from MySQL.
When there is no adaptive hash index contention, this value
remains zero and statements reserve the latch until they
finish. During times of contention, it counts down to zero,
and statements release the latch immediately after each row
lookup. When the adaptive hash index search system is
partitioned (controlled by
<a class="link" href="innodb-parameters.html#sysvar_innodb_adaptive_hash_index_parts">
<code class="literal">
innodb_adaptive_hash_index_parts
</code>
</a>
),
the value remains 0.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
TRX_IS_READ_ONLY
</code>
</p>
<p>
A value of 1 indicates the transaction is read only.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
TRX_AUTOCOMMIT_NON_LOCKING
</code>
</p>
<p>
A value of 1 indicates the transaction is a
<a class="link" href="select.html" title="15.2.13 SELECT Statement">
<code class="literal">
SELECT
</code>
</a>
statement that does not
use the
<code class="literal">
FOR UPDATE
</code>
or
<code class="literal">
LOCK IN
SHARED MODE
</code>
clauses, and is executing with
<a class="link" href="server-system-variables.html#sysvar_autocommit">
<code class="literal">
autocommit
</code>
</a>
enabled so that
the transaction contains only this one statement. When this
column and
<code class="literal">
TRX_IS_READ_ONLY
</code>
are both 1,
<code class="literal">
InnoDB
</code>
optimizes the transaction to reduce
the overhead associated with transactions that change table
data.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
TRX_SCHEDULE_WEIGHT
</code>
</p>
<p>
The transaction schedule weight assigned by the
Contention-Aware Transaction Scheduling (CATS) algorithm to
transactions waiting for a lock. The value is relative to the
values of other transactions. A higher value has a greater
weight. A value is computed only for transactions in a
<code class="literal">
LOCK WAIT
</code>
state, as reported by the
<code class="literal">
TRX_STATE
</code>
column. A NULL value is reported
for transactions that are not waiting for a lock. The
<code class="literal">
TRX_SCHEDULE_WEIGHT
</code>
value is different from
the
<code class="literal">
TRX_WEIGHT
</code>
value, which is computed by
a different algorithm for a different purpose.
</p>
</li>
</ul>
</div>
<h4>
<a name="idm46045076161248">
</a>
Example
</h4>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa76534383"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token operator">*</span> <span class="token keyword">FROM</span> INFORMATION_SCHEMA<span class="token punctuation">.</span>INNODB_TRX\G
<span class="token output"><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span> 1. row <span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span>
trx_id<span class="token punctuation">:</span> 1510
trx_state<span class="token punctuation">:</span> RUNNING
trx_started<span class="token punctuation">:</span> 2014-11-19 13<span class="token punctuation">:</span>24<span class="token punctuation">:</span>40
trx_requested_lock_id<span class="token punctuation">:</span> NULL
trx_wait_started<span class="token punctuation">:</span> NULL
trx_weight<span class="token punctuation">:</span> 586739
trx_mysql_thread_id<span class="token punctuation">:</span> 2
trx_query<span class="token punctuation">:</span> DELETE FROM employees.salaries WHERE salary > 65000
trx_operation_state<span class="token punctuation">:</span> updating or deleting
trx_tables_in_use<span class="token punctuation">:</span> 1
trx_tables_locked<span class="token punctuation">:</span> 1
trx_lock_structs<span class="token punctuation">:</span> 3003
trx_lock_memory_bytes<span class="token punctuation">:</span> 450768
trx_rows_locked<span class="token punctuation">:</span> 1407513
trx_rows_modified<span class="token punctuation">:</span> 583736
trx_concurrency_tickets<span class="token punctuation">:</span> 0
trx_isolation_level<span class="token punctuation">:</span> REPEATABLE READ
trx_unique_checks<span class="token punctuation">:</span> 1
trx_foreign_key_checks<span class="token punctuation">:</span> 1
trx_last_foreign_key_error<span class="token punctuation">:</span> NULL
trx_adaptive_hash_latched<span class="token punctuation">:</span> 0
trx_adaptive_hash_timeout<span class="token punctuation">:</span> 10000
trx_is_read_only<span class="token punctuation">:</span> 0
trx_autocommit_non_locking<span class="token punctuation">:</span> 0
trx_schedule_weight<span class="token punctuation">:</span> NULL</span></code></pre>
</div>
<h4>
<a name="idm46045076156432">
</a>
Notes
</h4>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
Use this table to help diagnose performance problems that
occur during times of heavy concurrent load. Its contents are
updated as described in
<a class="xref" href="innodb-information-schema-internal-data.html" title="17.15.2.3 Persistence and Consistency of InnoDB Transaction and Locking Information">
Section 17.15.2.3, “Persistence and Consistency of InnoDB Transaction and Locking
Information”
</a>
.
</p>
</li>
<li class="listitem">
<p>
You must have the
<a class="link" href="privileges-provided.html#priv_process">
<code class="literal">
PROCESS
</code>
</a>
privilege to query this table.
</p>
</li>
<li class="listitem">
<p>
Use the
<code class="literal">
INFORMATION_SCHEMA
</code>
<a class="link" href="information-schema-columns-table.html" title="28.3.8 The INFORMATION_SCHEMA COLUMNS Table">
<code class="literal">
COLUMNS
</code>
</a>
table or the
<a class="link" href="show-columns.html" title="15.7.7.6 SHOW COLUMNS Statement">
<code class="literal">
SHOW COLUMNS
</code>
</a>
statement to view
additional information about the columns of this table,
including data types and default values.
</p>
</li>
</ul>
</div>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/myisam-ftdump.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="myisam-ftdump">
</a>
6.6.3 myisam_ftdump — Display Full-Text Index information
</h3>
</div>
</div>
</div>
<a class="indexterm" name="idm46045307859232">
</a>
<p>
<a class="link" href="myisam-ftdump.html" title="6.6.3 myisam_ftdump — Display Full-Text Index information">
<span class="command">
<strong>
myisam_ftdump
</strong>
</span>
</a>
displays information about
<code class="literal">
FULLTEXT
</code>
indexes in
<code class="literal">
MyISAM
</code>
tables. It reads the
<code class="literal">
MyISAM
</code>
index file
directly, so it must be run on the server host where the table
is located. Before using
<a class="link" href="myisam-ftdump.html" title="6.6.3 myisam_ftdump — Display Full-Text Index information">
<span class="command">
<strong>
myisam_ftdump
</strong>
</span>
</a>
, be
sure to issue a
<code class="literal">
FLUSH TABLES
</code>
statement first
if the server is running.
</p>
<p>
<a class="link" href="myisam-ftdump.html" title="6.6.3 myisam_ftdump — Display Full-Text Index information">
<span class="command">
<strong>
myisam_ftdump
</strong>
</span>
</a>
scans and dumps the entire
index, which is not particularly fast. On the other hand, the
distribution of words changes infrequently, so it need not be
run often.
</p>
<p>
Invoke
<a class="link" href="myisam-ftdump.html" title="6.6.3 myisam_ftdump — Display Full-Text Index information">
<span class="command">
<strong>
myisam_ftdump
</strong>
</span>
</a>
like this:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-terminal"><div class="docs-select-all right" id="sa40674197"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal">myisam_ftdump <span class="token punctuation">[</span><em class="replaceable">options</em><span class="token punctuation">]</span> <em class="replaceable">tbl_name</em> <em class="replaceable">index_num</em></code></pre>
</div>
<p>
The
<em class="replaceable">
<code>
tbl_name
</code>
</em>
argument should be the
name of a
<code class="literal">
MyISAM
</code>
table. You can also specify
a table by naming its index file (the file with the
<code class="filename">
.MYI
</code>
suffix). If you do not invoke
<a class="link" href="myisam-ftdump.html" title="6.6.3 myisam_ftdump — Display Full-Text Index information">
<span class="command">
<strong>
myisam_ftdump
</strong>
</span>
</a>
in the directory where the
table files are located, the table or index file name must be
preceded by the path name to the table's database directory.
Index numbers begin with 0.
</p>
<p>
Example: Suppose that the
<code class="literal">
test
</code>
database
contains a table named
<code class="literal">
mytexttable
</code>
that has
the following definition:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa25498958"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">CREATE</span> <span class="token keyword">TABLE</span> mytexttable
<span class="token punctuation">(</span>
id <span class="token datatype">INT</span> <span class="token operator">NOT</span> <span class="token boolean">NULL</span><span class="token punctuation">,</span>
txt <span class="token datatype">TEXT</span> <span class="token operator">NOT</span> <span class="token boolean">NULL</span><span class="token punctuation">,</span>
<span class="token keyword">PRIMARY</span> <span class="token keyword">KEY</span> <span class="token punctuation">(</span>id<span class="token punctuation">)</span><span class="token punctuation">,</span>
<span class="token keyword">FULLTEXT</span> <span class="token punctuation">(</span>txt<span class="token punctuation">)</span>
<span class="token punctuation">)</span> <span class="token keyword">ENGINE</span><span class="token operator">=</span>MyISAM<span class="token punctuation">;</span></code></pre>
</div>
<p>
The index on
<code class="literal">
id
</code>
is index 0 and the
<code class="literal">
FULLTEXT
</code>
index on
<code class="literal">
txt
</code>
is
index 1. If your working directory is the
<code class="literal">
test
</code>
database directory, invoke
<a class="link" href="myisam-ftdump.html" title="6.6.3 myisam_ftdump — Display Full-Text Index information">
<span class="command">
<strong>
myisam_ftdump
</strong>
</span>
</a>
as follows:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-terminal"><div class="docs-select-all right" id="sa30774849"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal">myisam_ftdump mytexttable 1</code></pre>
</div>
<p>
If the path name to the
<code class="literal">
test
</code>
database
directory is
<code class="filename">
/usr/local/mysql/data/test
</code>
,
you can also specify the table name argument using that path
name. This is useful if you do not invoke
<a class="link" href="myisam-ftdump.html" title="6.6.3 myisam_ftdump — Display Full-Text Index information">
<span class="command">
<strong>
myisam_ftdump
</strong>
</span>
</a>
in the database directory:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-terminal"><div class="docs-select-all right" id="sa21727029"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal">myisam_ftdump /usr/local/mysql/data/test/mytexttable 1</code></pre>
</div>
<p>
You can use
<a class="link" href="myisam-ftdump.html" title="6.6.3 myisam_ftdump — Display Full-Text Index information">
<span class="command">
<strong>
myisam_ftdump
</strong>
</span>
</a>
to generate a list
of index entries in order of frequency of occurrence like this
on Unix-like systems:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-terminal"><div class="docs-select-all right" id="sa34041109"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal">myisam_ftdump <span class="token property">-c</span> mytexttable 1 | sort <span class="token property">-r</span></code></pre>
</div>
<p>
On Windows, use:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-terminal"><div class="docs-select-all right" id="sa421994"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal">myisam_ftdump <span class="token property">-c</span> mytexttable 1 | sort /R</code></pre>
</div>
<p>
<a class="link" href="myisam-ftdump.html" title="6.6.3 myisam_ftdump — Display Full-Text Index information">
<span class="command">
<strong>
myisam_ftdump
</strong>
</span>
</a>
supports the following options:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<a name="option_myisam_ftdump_help">
</a>
<a class="link" href="myisam-ftdump.html#option_myisam_ftdump_help">
<code class="option">
--help
</code>
</a>
,
<code class="option">
-h
</code>
<code class="option">
-?
</code>
</p>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for help">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--help
</code>
</td>
</tr>
</tbody>
</table>
</div>
<a class="indexterm" name="idm46045307814608">
</a>
<a class="indexterm" name="idm46045307813120">
</a>
<p>
Display a help message and exit.
</p>
</li>
<li class="listitem">
<p>
<a name="option_myisam_ftdump_count">
</a>
<a class="link" href="myisam-ftdump.html#option_myisam_ftdump_count">
<code class="option">
--count
</code>
</a>
,
<code class="option">
-c
</code>
</p>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for count">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--count
</code>
</td>
</tr>
</tbody>
</table>
</div>
<a class="indexterm" name="idm46045307802944">
</a>
<a class="indexterm" name="idm46045307801456">
</a>
<p>
Calculate per-word statistics (counts and global weights).
</p>
</li>
<li class="listitem">
<p>
<a name="option_myisam_ftdump_dump">
</a>
<a class="link" href="myisam-ftdump.html#option_myisam_ftdump_dump">
<code class="option">
--dump
</code>
</a>
,
<code class="option">
-d
</code>
</p>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for dump">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--dump
</code>
</td>
</tr>
</tbody>
</table>
</div>
<a class="indexterm" name="idm46045307791312">
</a>
<a class="indexterm" name="idm46045307789824">
</a>
<p>
Dump the index, including data offsets and word weights.
</p>
</li>
<li class="listitem">
<p>
<a name="option_myisam_ftdump_length">
</a>
<a class="link" href="myisam-ftdump.html#option_myisam_ftdump_length">
<code class="option">
--length
</code>
</a>
,
<code class="option">
-l
</code>
</p>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for length">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--length
</code>
</td>
</tr>
</tbody>
</table>
</div>
<a class="indexterm" name="idm46045307779680">
</a>
<a class="indexterm" name="idm46045307778192">
</a>
<p>
Report the length distribution.
</p>
</li>
<li class="listitem">
<p>
<a name="option_myisam_ftdump_stats">
</a>
<a class="link" href="myisam-ftdump.html#option_myisam_ftdump_stats">
<code class="option">
--stats
</code>
</a>
,
<code class="option">
-s
</code>
</p>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for stats">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--stats
</code>
</td>
</tr>
</tbody>
</table>
</div>
<a class="indexterm" name="idm46045307768032">
</a>
<a class="indexterm" name="idm46045307766544">
</a>
<p>
Report global index statistics. This is the default
operation if no other operation is specified.
</p>
</li>
<li class="listitem">
<p>
<a name="option_myisam_ftdump_verbose">
</a>
<a class="link" href="myisam-ftdump.html#option_myisam_ftdump_verbose">
<code class="option">
--verbose
</code>
</a>
,
<code class="option">
-v
</code>
</p>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for verbose">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--verbose
</code>
</td>
</tr>
</tbody>
</table>
</div>
<a class="indexterm" name="idm46045307756352">
</a>
<a class="indexterm" name="idm46045307754864">
</a>
<p>
Verbose mode. Print more output about what the program does.
</p>
</li>
</ul>
</div>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/dynindex-sysvar.html | <div id="docs-body">
<div class="index">
<div class="titlepage">
<div>
<div>
<h2 class="title">
<a name="dynindex-sysvar">
</a>
System Variable Index
</h2>
</div>
</div>
</div>
<p>
<a name="sysvar-index-top">
</a>
<a class="link" href="dynindex-sysvar.html#sysvar-index-A" title="A">
A
</a>
|
<a class="link" href="dynindex-sysvar.html#sysvar-index-B" title="B">
B
</a>
|
<a class="link" href="dynindex-sysvar.html#sysvar-index-C" title="C">
C
</a>
|
<a class="link" href="dynindex-sysvar.html#sysvar-index-D" title="D">
D
</a>
|
<a class="link" href="dynindex-sysvar.html#sysvar-index-E" title="E">
E
</a>
|
<a class="link" href="dynindex-sysvar.html#sysvar-index-F" title="F">
F
</a>
|
<a class="link" href="dynindex-sysvar.html#sysvar-index-G" title="G">
G
</a>
|
<a class="link" href="dynindex-sysvar.html#sysvar-index-H" title="H">
H
</a>
|
<a class="link" href="dynindex-sysvar.html#sysvar-index-I" title="I">
I
</a>
|
<a class="link" href="dynindex-sysvar.html#sysvar-index-J" title="J">
J
</a>
|
<a class="link" href="dynindex-sysvar.html#sysvar-index-K" title="K">
K
</a>
|
<a class="link" href="dynindex-sysvar.html#sysvar-index-L" title="L">
L
</a>
|
<a class="link" href="dynindex-sysvar.html#sysvar-index-M" title="M">
M
</a>
|
<a class="link" href="dynindex-sysvar.html#sysvar-index-N" title="N">
N
</a>
|
<a class="link" href="dynindex-sysvar.html#sysvar-index-O" title="O">
O
</a>
|
<a class="link" href="dynindex-sysvar.html#sysvar-index-P" title="P">
P
</a>
|
<a class="link" href="dynindex-sysvar.html#sysvar-index-Q" title="Q">
Q
</a>
|
<a class="link" href="dynindex-sysvar.html#sysvar-index-R" title="R">
R
</a>
|
<a class="link" href="dynindex-sysvar.html#sysvar-index-S" title="S">
S
</a>
|
<a class="link" href="dynindex-sysvar.html#sysvar-index-T" title="T">
T
</a>
|
<a class="link" href="dynindex-sysvar.html#sysvar-index-U" title="U">
U
</a>
|
<a class="link" href="dynindex-sysvar.html#sysvar-index-V" title="V">
V
</a>
|
<a class="link" href="dynindex-sysvar.html#sysvar-index-W" title="W">
W
</a>
|
<a class="link" href="dynindex-sysvar.html#sysvar-index-X" title="X">
X
</a>
</p>
<div class="indexdiv">
<a name="sysvar-index-A">
</a>
<h3 class="title">
A
</h3>
<p>
[
<a class="link" href="dynindex-sysvar.html#sysvar-index-top">
index top
</a>
]
</p>
<dl>
<dt>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
activate_all_roles_on_login
</h3>
<dl>
<dt>
<a class="xref" href="create-procedure.html" title="15.1.17 CREATE PROCEDURE and CREATE FUNCTION Statements">
Section 15.1.17, “CREATE PROCEDURE and CREATE FUNCTION Statements”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-privilege-checks.html" title="19.3.3 Replication Privilege Checks">
Section 19.3.3, “Replication Privilege Checks”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="set-role.html" title="15.7.1.11 SET ROLE Statement">
Section 15.7.1.11, “SET ROLE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="show-grants.html" title="15.7.7.22 SHOW GRANTS Statement">
Section 15.7.7.22, “SHOW GRANTS Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="stored-objects-security.html" title="27.6 Stored Object Access Control">
Section 27.6, “Stored Object Access Control”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="roles.html" title="8.2.10 Using Roles">
Section 8.2.10, “Using Roles”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
admin
</h3>
<dl>
<dt>
<a class="xref" href="encrypted-connection-protocols-ciphers.html" title="8.3.2 Encrypted Connection TLS Protocols and Ciphers">
Section 8.3.2, “Encrypted Connection TLS Protocols and Ciphers”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
admin_address
</h3>
<dl>
<dt>
<a class="xref" href="administrative-connection-interface.html" title="7.1.12.2 Administrative Connection Management">
Section 7.1.12.2, “Administrative Connection Management”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="network-namespace-support.html" title="7.1.14 Network Namespace Support">
Section 7.1.14, “Network Namespace Support”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-distributed-recovery-connections.html#group-replication-distributed-recovery-connections-endpoints" title="20.5.4.1.1 Selecting addresses for distributed recovery endpoints">
Section 20.5.4.1.1, “Selecting addresses for distributed recovery endpoints”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
admin_port
</h3>
<dl>
<dt>
<a class="xref" href="administrative-connection-interface.html" title="7.1.12.2 Administrative Connection Management">
Section 7.1.12.2, “Administrative Connection Management”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-distributed-recovery-connections.html#group-replication-distributed-recovery-connections-endpoints" title="20.5.4.1.1 Selecting addresses for distributed recovery endpoints">
Section 20.5.4.1.1, “Selecting addresses for distributed recovery endpoints”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
admin_ssl_ca
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
admin_ssl_capath
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
admin_ssl_cert
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
admin_ssl_cipher
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
admin_ssl_crl
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
admin_ssl_crlpath
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
admin_ssl_key
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
admin_tls_ciphersuites
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
admin_tls_version
</h3>
<dl>
<dt>
<a class="xref" href="administrative-connection-interface.html" title="7.1.12.2 Administrative Connection Management">
Section 7.1.12.2, “Administrative Connection Management”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="encrypted-connection-protocols-ciphers.html" title="8.3.2 Encrypted Connection TLS Protocols and Ciphers">
Section 8.3.2, “Encrypted Connection TLS Protocols and Ciphers”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
audit_log_buffer_size
</h3>
<dl>
<dt>
<a class="xref" href="audit-log-reference.html" title="8.4.5.11 Audit Log Reference">
Section 8.4.5.11, “Audit Log Reference”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="audit-log-logging-configuration.html" title="8.4.5.5 Configuring Audit Logging Characteristics">
Section 8.4.5.5, “Configuring Audit Logging Characteristics”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
audit_log_compression
</h3>
<dl>
<dt>
<a class="xref" href="audit-log-reference.html" title="8.4.5.11 Audit Log Reference">
Section 8.4.5.11, “Audit Log Reference”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="audit-log-logging-configuration.html" title="8.4.5.5 Configuring Audit Logging Characteristics">
Section 8.4.5.5, “Configuring Audit Logging Characteristics”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
audit_log_connection_policy
</h3>
<dl>
<dt>
<a class="xref" href="audit-log-reference.html" title="8.4.5.11 Audit Log Reference">
Section 8.4.5.11, “Audit Log Reference”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="audit-log-legacy-filtering.html" title="8.4.5.10 Legacy Mode Audit Log Filtering">
Section 8.4.5.10, “Legacy Mode Audit Log Filtering”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="audit-log-filter-definitions.html" title="8.4.5.8 Writing Audit Log Filter Definitions">
Section 8.4.5.8, “Writing Audit Log Filter Definitions”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
audit_log_current_session
</h3>
<dl>
<dt>
<a class="xref" href="audit-log-reference.html" title="8.4.5.11 Audit Log Reference">
Section 8.4.5.11, “Audit Log Reference”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
audit_log_database
</h3>
<dl>
<dt>
<a class="xref" href="audit-log-reference.html" title="8.4.5.11 Audit Log Reference">
Section 8.4.5.11, “Audit Log Reference”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="audit-log-elements.html" title="8.4.5.1 Elements of MySQL Enterprise Audit">
Section 8.4.5.1, “Elements of MySQL Enterprise Audit”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="audit-log.html" title="8.4.5 MySQL Enterprise Audit">
Section 8.4.5, “MySQL Enterprise Audit”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
audit_log_disable
</h3>
<dl>
<dt>
<a class="xref" href="audit-log-reference.html" title="8.4.5.11 Audit Log Reference">
Section 8.4.5.11, “Audit Log Reference”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="audit-log-disabling.html" title="8.4.5.9 Disabling Audit Logging">
Section 8.4.5.9, “Disabling Audit Logging”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
audit_log_encryption
</h3>
<dl>
<dt>
<a class="xref" href="audit-log-reference.html" title="8.4.5.11 Audit Log Reference">
Section 8.4.5.11, “Audit Log Reference”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="audit-log-logging-configuration.html" title="8.4.5.5 Configuring Audit Logging Characteristics">
Section 8.4.5.5, “Configuring Audit Logging Characteristics”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
audit_log_exclude_accounts
</h3>
<dl>
<dt>
<a class="xref" href="audit-log-reference.html" title="8.4.5.11 Audit Log Reference">
Section 8.4.5.11, “Audit Log Reference”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="audit-log-legacy-filtering.html" title="8.4.5.10 Legacy Mode Audit Log Filtering">
Section 8.4.5.10, “Legacy Mode Audit Log Filtering”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="audit-log-filter-definitions.html" title="8.4.5.8 Writing Audit Log Filter Definitions">
Section 8.4.5.8, “Writing Audit Log Filter Definitions”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
audit_log_file
</h3>
<dl>
<dt>
<a class="xref" href="audit-log-file-formats.html" title="8.4.5.4 Audit Log File Formats">
Section 8.4.5.4, “Audit Log File Formats”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="audit-log-reference.html" title="8.4.5.11 Audit Log Reference">
Section 8.4.5.11, “Audit Log Reference”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="audit-log-logging-configuration.html" title="8.4.5.5 Configuring Audit Logging Characteristics">
Section 8.4.5.5, “Configuring Audit Logging Characteristics”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="docker-mysql-more-topics.html" title="2.5.6.2 More Topics on Deploying MySQL Server with Docker">
Section 2.5.6.2, “More Topics on Deploying MySQL Server with Docker”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="audit-log.html" title="8.4.5 MySQL Enterprise Audit">
Section 8.4.5, “MySQL Enterprise Audit”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="audit-log-security.html" title="8.4.5.3 MySQL Enterprise Audit Security Considerations">
Section 8.4.5.3, “MySQL Enterprise Audit Security Considerations”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="audit-log-file-reading.html" title="8.4.5.6 Reading Audit Log Files">
Section 8.4.5.6, “Reading Audit Log Files”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
audit_log_filter_id
</h3>
<dl>
<dt>
<a class="xref" href="audit-log-filtering.html" title="8.4.5.7 Audit Log Filtering">
Section 8.4.5.7, “Audit Log Filtering”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="audit-log-reference.html" title="8.4.5.11 Audit Log Reference">
Section 8.4.5.11, “Audit Log Reference”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="audit-log-filter-definitions.html" title="8.4.5.8 Writing Audit Log Filter Definitions">
Section 8.4.5.8, “Writing Audit Log Filter Definitions”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
audit_log_flush
</h3>
<dl>
<dt>
<a class="xref" href="audit-log-reference.html" title="8.4.5.11 Audit Log Reference">
Section 8.4.5.11, “Audit Log Reference”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="audit-log-logging-configuration.html" title="8.4.5.5 Configuring Audit Logging Characteristics">
Section 8.4.5.5, “Configuring Audit Logging Characteristics”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
audit_log_flush_interval_seconds
</h3>
<dl>
<dt>
<a class="xref" href="audit-log-reference.html" title="8.4.5.11 Audit Log Reference">
Section 8.4.5.11, “Audit Log Reference”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="audit-log-logging-configuration.html" title="8.4.5.5 Configuring Audit Logging Characteristics">
Section 8.4.5.5, “Configuring Audit Logging Characteristics”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-component-scheduler-tasks-table.html" title="29.12.22.1 The component_scheduler_tasks Table">
Section 29.12.22.1, “The component_scheduler_tasks Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
audit_log_format
</h3>
<dl>
<dt>
<a class="xref" href="audit-log-file-formats.html" title="8.4.5.4 Audit Log File Formats">
Section 8.4.5.4, “Audit Log File Formats”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="audit-log-reference.html" title="8.4.5.11 Audit Log Reference">
Section 8.4.5.11, “Audit Log Reference”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="audit-log-logging-configuration.html" title="8.4.5.5 Configuring Audit Logging Characteristics">
Section 8.4.5.5, “Configuring Audit Logging Characteristics”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="audit-log.html" title="8.4.5 MySQL Enterprise Audit">
Section 8.4.5, “MySQL Enterprise Audit”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="audit-api-message-emit.html" title="8.4.6 The Audit Message Component">
Section 8.4.6, “The Audit Message Component”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
audit_log_format_unix_timestamp
</h3>
<dl>
<dt>
<a class="xref" href="audit-log-file-formats.html" title="8.4.5.4 Audit Log File Formats">
Section 8.4.5.4, “Audit Log File Formats”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="audit-log-reference.html" title="8.4.5.11 Audit Log Reference">
Section 8.4.5.11, “Audit Log Reference”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="audit-log-logging-configuration.html" title="8.4.5.5 Configuring Audit Logging Characteristics">
Section 8.4.5.5, “Configuring Audit Logging Characteristics”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
audit_log_include_accounts
</h3>
<dl>
<dt>
<a class="xref" href="audit-log-reference.html" title="8.4.5.11 Audit Log Reference">
Section 8.4.5.11, “Audit Log Reference”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="audit-log-legacy-filtering.html" title="8.4.5.10 Legacy Mode Audit Log Filtering">
Section 8.4.5.10, “Legacy Mode Audit Log Filtering”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="audit-log-filter-definitions.html" title="8.4.5.8 Writing Audit Log Filter Definitions">
Section 8.4.5.8, “Writing Audit Log Filter Definitions”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
audit_log_max_size
</h3>
<dl>
<dt>
<a class="xref" href="audit-log-reference.html" title="8.4.5.11 Audit Log Reference">
Section 8.4.5.11, “Audit Log Reference”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="audit-log-logging-configuration.html" title="8.4.5.5 Configuring Audit Logging Characteristics">
Section 8.4.5.5, “Configuring Audit Logging Characteristics”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
audit_log_password_history_keep_days
</h3>
<dl>
<dt>
<a class="xref" href="audit-log-reference.html" title="8.4.5.11 Audit Log Reference">
Section 8.4.5.11, “Audit Log Reference”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="audit-log-logging-configuration.html" title="8.4.5.5 Configuring Audit Logging Characteristics">
Section 8.4.5.5, “Configuring Audit Logging Characteristics”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
audit_log_policy
</h3>
<dl>
<dt>
<a class="xref" href="audit-log-reference.html" title="8.4.5.11 Audit Log Reference">
Section 8.4.5.11, “Audit Log Reference”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="audit-log-legacy-filtering.html" title="8.4.5.10 Legacy Mode Audit Log Filtering">
Section 8.4.5.10, “Legacy Mode Audit Log Filtering”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="using-system-variables.html" title="7.1.9 Using System Variables">
Section 7.1.9, “Using System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="audit-log-filter-definitions.html" title="8.4.5.8 Writing Audit Log Filter Definitions">
Section 8.4.5.8, “Writing Audit Log Filter Definitions”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
audit_log_prune_seconds
</h3>
<dl>
<dt>
<a class="xref" href="audit-log-reference.html" title="8.4.5.11 Audit Log Reference">
Section 8.4.5.11, “Audit Log Reference”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="audit-log-logging-configuration.html" title="8.4.5.5 Configuring Audit Logging Characteristics">
Section 8.4.5.5, “Configuring Audit Logging Characteristics”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
audit_log_read_buffer_size
</h3>
<dl>
<dt>
<a class="xref" href="audit-log-reference.html" title="8.4.5.11 Audit Log Reference">
Section 8.4.5.11, “Audit Log Reference”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="audit-log-file-reading.html" title="8.4.5.6 Reading Audit Log Files">
Section 8.4.5.6, “Reading Audit Log Files”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
audit_log_rotate_on_size
</h3>
<dl>
<dt>
<a class="xref" href="audit-log-reference.html" title="8.4.5.11 Audit Log Reference">
Section 8.4.5.11, “Audit Log Reference”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="audit-log-logging-configuration.html" title="8.4.5.5 Configuring Audit Logging Characteristics">
Section 8.4.5.5, “Configuring Audit Logging Characteristics”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
audit_log_statement_policy
</h3>
<dl>
<dt>
<a class="xref" href="audit-log-reference.html" title="8.4.5.11 Audit Log Reference">
Section 8.4.5.11, “Audit Log Reference”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="audit-log-legacy-filtering.html" title="8.4.5.10 Legacy Mode Audit Log Filtering">
Section 8.4.5.10, “Legacy Mode Audit Log Filtering”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="audit-log-filter-definitions.html" title="8.4.5.8 Writing Audit Log Filter Definitions">
Section 8.4.5.8, “Writing Audit Log Filter Definitions”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
audit_log_strategy
</h3>
<dl>
<dt>
<a class="xref" href="audit-log-reference.html" title="8.4.5.11 Audit Log Reference">
Section 8.4.5.11, “Audit Log Reference”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="audit-log-logging-configuration.html" title="8.4.5.5 Configuring Audit Logging Characteristics">
Section 8.4.5.5, “Configuring Audit Logging Characteristics”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
authentication_kerberos_service_key_tab
</h3>
<dl>
<dt>
<a class="xref" href="kerberos-pluggable-authentication.html" title="8.4.1.8 Kerberos Pluggable Authentication">
Section 8.4.1.8, “Kerberos Pluggable Authentication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="pluggable-authentication-system-variables.html" title="8.4.1.13 Pluggable Authentication System Variables">
Section 8.4.1.13, “Pluggable Authentication System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
authentication_kerberos_service_principal
</h3>
<dl>
<dt>
<a class="xref" href="kerberos-pluggable-authentication.html" title="8.4.1.8 Kerberos Pluggable Authentication">
Section 8.4.1.8, “Kerberos Pluggable Authentication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="pluggable-authentication-system-variables.html" title="8.4.1.13 Pluggable Authentication System Variables">
Section 8.4.1.13, “Pluggable Authentication System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
authentication_ldap_sasl_auth_method_name
</h3>
<dl>
<dt>
<a class="xref" href="ldap-pluggable-authentication.html" title="8.4.1.7 LDAP Pluggable Authentication">
Section 8.4.1.7, “LDAP Pluggable Authentication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="pluggable-authentication-system-variables.html" title="8.4.1.13 Pluggable Authentication System Variables">
Section 8.4.1.13, “Pluggable Authentication System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
authentication_ldap_sasl_bind_base_dn
</h3>
<dl>
<dt>
<a class="xref" href="ldap-pluggable-authentication.html" title="8.4.1.7 LDAP Pluggable Authentication">
Section 8.4.1.7, “LDAP Pluggable Authentication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="pluggable-authentication-system-variables.html" title="8.4.1.13 Pluggable Authentication System Variables">
Section 8.4.1.13, “Pluggable Authentication System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
authentication_ldap_sasl_bind_root_dn
</h3>
<dl>
<dt>
<a class="xref" href="ldap-pluggable-authentication.html" title="8.4.1.7 LDAP Pluggable Authentication">
Section 8.4.1.7, “LDAP Pluggable Authentication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="pluggable-authentication-system-variables.html" title="8.4.1.13 Pluggable Authentication System Variables">
Section 8.4.1.13, “Pluggable Authentication System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
authentication_ldap_sasl_bind_root_pwd
</h3>
<dl>
<dt>
<a class="xref" href="ldap-pluggable-authentication.html" title="8.4.1.7 LDAP Pluggable Authentication">
Section 8.4.1.7, “LDAP Pluggable Authentication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="pluggable-authentication-system-variables.html" title="8.4.1.13 Pluggable Authentication System Variables">
Section 8.4.1.13, “Pluggable Authentication System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
authentication_ldap_sasl_ca_path
</h3>
<dl>
<dt>
<a class="xref" href="ldap-pluggable-authentication.html" title="8.4.1.7 LDAP Pluggable Authentication">
Section 8.4.1.7, “LDAP Pluggable Authentication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="pluggable-authentication-system-variables.html" title="8.4.1.13 Pluggable Authentication System Variables">
Section 8.4.1.13, “Pluggable Authentication System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
authentication_ldap_sasl_connect_timeout
</h3>
<dl>
<dt>
<a class="xref" href="ldap-pluggable-authentication.html" title="8.4.1.7 LDAP Pluggable Authentication">
Section 8.4.1.7, “LDAP Pluggable Authentication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="pluggable-authentication-system-variables.html" title="8.4.1.13 Pluggable Authentication System Variables">
Section 8.4.1.13, “Pluggable Authentication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
authentication_ldap_sasl_group_search_attr
</h3>
<dl>
<dt>
<a class="xref" href="ldap-pluggable-authentication.html" title="8.4.1.7 LDAP Pluggable Authentication">
Section 8.4.1.7, “LDAP Pluggable Authentication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="pluggable-authentication-system-variables.html" title="8.4.1.13 Pluggable Authentication System Variables">
Section 8.4.1.13, “Pluggable Authentication System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
authentication_ldap_sasl_group_search_filter
</h3>
<dl>
<dt>
<a class="xref" href="pluggable-authentication-system-variables.html" title="8.4.1.13 Pluggable Authentication System Variables">
Section 8.4.1.13, “Pluggable Authentication System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
authentication_ldap_sasl_init_pool_size
</h3>
<dl>
<dt>
<a class="xref" href="pluggable-authentication-system-variables.html" title="8.4.1.13 Pluggable Authentication System Variables">
Section 8.4.1.13, “Pluggable Authentication System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
authentication_ldap_sasl_log_status
</h3>
<dl>
<dt>
<a class="xref" href="pluggable-authentication-system-variables.html" title="8.4.1.13 Pluggable Authentication System Variables">
Section 8.4.1.13, “Pluggable Authentication System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
authentication_ldap_sasl_max_pool_size
</h3>
<dl>
<dt>
<a class="xref" href="ldap-pluggable-authentication.html" title="8.4.1.7 LDAP Pluggable Authentication">
Section 8.4.1.7, “LDAP Pluggable Authentication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="pluggable-authentication-system-variables.html" title="8.4.1.13 Pluggable Authentication System Variables">
Section 8.4.1.13, “Pluggable Authentication System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
authentication_ldap_sasl_referral
</h3>
<dl>
<dt>
<a class="xref" href="ldap-pluggable-authentication.html" title="8.4.1.7 LDAP Pluggable Authentication">
Section 8.4.1.7, “LDAP Pluggable Authentication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="pluggable-authentication-system-variables.html" title="8.4.1.13 Pluggable Authentication System Variables">
Section 8.4.1.13, “Pluggable Authentication System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
authentication_ldap_sasl_response_timeout
</h3>
<dl>
<dt>
<a class="xref" href="ldap-pluggable-authentication.html" title="8.4.1.7 LDAP Pluggable Authentication">
Section 8.4.1.7, “LDAP Pluggable Authentication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="pluggable-authentication-system-variables.html" title="8.4.1.13 Pluggable Authentication System Variables">
Section 8.4.1.13, “Pluggable Authentication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
authentication_ldap_sasl_server_host
</h3>
<dl>
<dt>
<a class="xref" href="ldap-pluggable-authentication.html" title="8.4.1.7 LDAP Pluggable Authentication">
Section 8.4.1.7, “LDAP Pluggable Authentication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="pluggable-authentication-system-variables.html" title="8.4.1.13 Pluggable Authentication System Variables">
Section 8.4.1.13, “Pluggable Authentication System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
authentication_ldap_sasl_server_port
</h3>
<dl>
<dt>
<a class="xref" href="ldap-pluggable-authentication.html" title="8.4.1.7 LDAP Pluggable Authentication">
Section 8.4.1.7, “LDAP Pluggable Authentication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="pluggable-authentication-system-variables.html" title="8.4.1.13 Pluggable Authentication System Variables">
Section 8.4.1.13, “Pluggable Authentication System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
authentication_ldap_sasl_tls
</h3>
<dl>
<dt>
<a class="xref" href="ldap-pluggable-authentication.html" title="8.4.1.7 LDAP Pluggable Authentication">
Section 8.4.1.7, “LDAP Pluggable Authentication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="pluggable-authentication-system-variables.html" title="8.4.1.13 Pluggable Authentication System Variables">
Section 8.4.1.13, “Pluggable Authentication System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
authentication_ldap_sasl_user_search_attr
</h3>
<dl>
<dt>
<a class="xref" href="ldap-pluggable-authentication.html" title="8.4.1.7 LDAP Pluggable Authentication">
Section 8.4.1.7, “LDAP Pluggable Authentication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="pluggable-authentication-system-variables.html" title="8.4.1.13 Pluggable Authentication System Variables">
Section 8.4.1.13, “Pluggable Authentication System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
authentication_ldap_simple_auth_method_name
</h3>
<dl>
<dt>
<a class="xref" href="ldap-pluggable-authentication.html" title="8.4.1.7 LDAP Pluggable Authentication">
Section 8.4.1.7, “LDAP Pluggable Authentication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="pluggable-authentication-system-variables.html" title="8.4.1.13 Pluggable Authentication System Variables">
Section 8.4.1.13, “Pluggable Authentication System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
authentication_ldap_simple_bind_base_dn
</h3>
<dl>
<dt>
<a class="xref" href="pluggable-authentication-system-variables.html" title="8.4.1.13 Pluggable Authentication System Variables">
Section 8.4.1.13, “Pluggable Authentication System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
authentication_ldap_simple_bind_root_dn
</h3>
<dl>
<dt>
<a class="xref" href="pluggable-authentication-system-variables.html" title="8.4.1.13 Pluggable Authentication System Variables">
Section 8.4.1.13, “Pluggable Authentication System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
authentication_ldap_simple_bind_root_pwd
</h3>
<dl>
<dt>
<a class="xref" href="pluggable-authentication-system-variables.html" title="8.4.1.13 Pluggable Authentication System Variables">
Section 8.4.1.13, “Pluggable Authentication System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
authentication_ldap_simple_ca_path
</h3>
<dl>
<dt>
<a class="xref" href="ldap-pluggable-authentication.html" title="8.4.1.7 LDAP Pluggable Authentication">
Section 8.4.1.7, “LDAP Pluggable Authentication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="pluggable-authentication-system-variables.html" title="8.4.1.13 Pluggable Authentication System Variables">
Section 8.4.1.13, “Pluggable Authentication System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
authentication_ldap_simple_connect_timeout
</h3>
<dl>
<dt>
<a class="xref" href="ldap-pluggable-authentication.html" title="8.4.1.7 LDAP Pluggable Authentication">
Section 8.4.1.7, “LDAP Pluggable Authentication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="pluggable-authentication-system-variables.html" title="8.4.1.13 Pluggable Authentication System Variables">
Section 8.4.1.13, “Pluggable Authentication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
authentication_ldap_simple_group_search_attr
</h3>
<dl>
<dt>
<a class="xref" href="ldap-pluggable-authentication.html" title="8.4.1.7 LDAP Pluggable Authentication">
Section 8.4.1.7, “LDAP Pluggable Authentication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="pluggable-authentication-system-variables.html" title="8.4.1.13 Pluggable Authentication System Variables">
Section 8.4.1.13, “Pluggable Authentication System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
authentication_ldap_simple_group_search_filter
</h3>
<dl>
<dt>
<a class="xref" href="pluggable-authentication-system-variables.html" title="8.4.1.13 Pluggable Authentication System Variables">
Section 8.4.1.13, “Pluggable Authentication System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
authentication_ldap_simple_init_pool_size
</h3>
<dl>
<dt>
<a class="xref" href="pluggable-authentication-system-variables.html" title="8.4.1.13 Pluggable Authentication System Variables">
Section 8.4.1.13, “Pluggable Authentication System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
authentication_ldap_simple_log_status
</h3>
<dl>
<dt>
<a class="xref" href="pluggable-authentication-system-variables.html" title="8.4.1.13 Pluggable Authentication System Variables">
Section 8.4.1.13, “Pluggable Authentication System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
authentication_ldap_simple_max_pool_size
</h3>
<dl>
<dt>
<a class="xref" href="pluggable-authentication-system-variables.html" title="8.4.1.13 Pluggable Authentication System Variables">
Section 8.4.1.13, “Pluggable Authentication System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
authentication_ldap_simple_referral
</h3>
<dl>
<dt>
<a class="xref" href="ldap-pluggable-authentication.html" title="8.4.1.7 LDAP Pluggable Authentication">
Section 8.4.1.7, “LDAP Pluggable Authentication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="pluggable-authentication-system-variables.html" title="8.4.1.13 Pluggable Authentication System Variables">
Section 8.4.1.13, “Pluggable Authentication System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
authentication_ldap_simple_response_timeout
</h3>
<dl>
<dt>
<a class="xref" href="ldap-pluggable-authentication.html" title="8.4.1.7 LDAP Pluggable Authentication">
Section 8.4.1.7, “LDAP Pluggable Authentication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="pluggable-authentication-system-variables.html" title="8.4.1.13 Pluggable Authentication System Variables">
Section 8.4.1.13, “Pluggable Authentication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
authentication_ldap_simple_server_host
</h3>
<dl>
<dt>
<a class="xref" href="pluggable-authentication-system-variables.html" title="8.4.1.13 Pluggable Authentication System Variables">
Section 8.4.1.13, “Pluggable Authentication System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
authentication_ldap_simple_server_port
</h3>
<dl>
<dt>
<a class="xref" href="pluggable-authentication-system-variables.html" title="8.4.1.13 Pluggable Authentication System Variables">
Section 8.4.1.13, “Pluggable Authentication System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
authentication_ldap_simple_tls
</h3>
<dl>
<dt>
<a class="xref" href="ldap-pluggable-authentication.html" title="8.4.1.7 LDAP Pluggable Authentication">
Section 8.4.1.7, “LDAP Pluggable Authentication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="pluggable-authentication-system-variables.html" title="8.4.1.13 Pluggable Authentication System Variables">
Section 8.4.1.13, “Pluggable Authentication System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
authentication_ldap_simple_user_search_attr
</h3>
<dl>
<dt>
<a class="xref" href="ldap-pluggable-authentication.html" title="8.4.1.7 LDAP Pluggable Authentication">
Section 8.4.1.7, “LDAP Pluggable Authentication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="pluggable-authentication-system-variables.html" title="8.4.1.13 Pluggable Authentication System Variables">
Section 8.4.1.13, “Pluggable Authentication System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
authentication_policy
</h3>
<dl>
<dt>
<a class="xref" href="alter-user.html" title="15.7.1.1 ALTER USER Statement">
Section 15.7.1.1, “ALTER USER Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="caching-sha2-pluggable-authentication.html" title="8.4.1.2 Caching SHA-2 Pluggable Authentication">
Section 8.4.1.2, “Caching SHA-2 Pluggable Authentication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="create-user.html" title="15.7.1.3 CREATE USER Statement">
Section 15.7.1.3, “CREATE USER Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="multifactor-authentication.html" title="8.2.18 Multifactor Authentication">
Section 8.2.18, “Multifactor Authentication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="pluggable-authentication.html" title="8.2.17 Pluggable Authentication">
Section 8.2.17, “Pluggable Authentication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="privileges-provided.html" title="8.2.2 Privileges Provided by MySQL">
Section 8.2.2, “Privileges Provided by MySQL”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="sha256-pluggable-authentication.html" title="8.4.1.3 SHA-256 Pluggable Authentication">
Section 8.4.1.3, “SHA-256 Pluggable Authentication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="webauthn-pluggable-authentication.html" title="8.4.1.11 WebAuthn Pluggable Authentication">
Section 8.4.1.11, “WebAuthn Pluggable Authentication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
authentication_webauthn_rp_id
</h3>
<dl>
<dt>
<a class="xref" href="mysql-command-options.html" title="6.5.1.1 mysql Client Options">
Section 6.5.1.1, “mysql Client Options”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="pluggable-authentication-system-variables.html" title="8.4.1.13 Pluggable Authentication System Variables">
Section 8.4.1.13, “Pluggable Authentication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="webauthn-pluggable-authentication.html" title="8.4.1.11 WebAuthn Pluggable Authentication">
Section 8.4.1.11, “WebAuthn Pluggable Authentication”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
authentication_windows_log_level
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="windows-pluggable-authentication.html" title="8.4.1.6 Windows Pluggable Authentication">
Section 8.4.1.6, “Windows Pluggable Authentication”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
authentication_windows_use_principal_name
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="windows-pluggable-authentication.html" title="8.4.1.6 Windows Pluggable Authentication">
Section 8.4.1.6, “Windows Pluggable Authentication”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
auto_generate_certs
</h3>
<dl>
<dt>
<a class="xref" href="creating-ssl-rsa-files-using-mysql.html" title="8.3.3.1 Creating SSL and RSA Certificates and Keys using MySQL">
Section 8.3.3.1, “Creating SSL and RSA Certificates and Keys using MySQL”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
auto_increment_increment
</h3>
<dl>
<dt>
<a class="xref" href="innodb-auto-increment-handling.html" title="17.6.1.6 AUTO_INCREMENT Handling in InnoDB">
Section 17.6.1.6, “AUTO_INCREMENT Handling in InnoDB”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-frequently-asked-questions.html" title="20.10 Frequently Asked Questions">
Section 20.10, “Frequently Asked Questions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log-mixed.html" title="7.4.4.3 Mixed Binary Logging Format">
Section 7.4.4.3, “Mixed Binary Logging Format”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="faqs-general.html" title="A.1 MySQL 8.4 FAQ: General">
Section A.1, “MySQL 8.4 FAQ: General”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-programs-ndb-import.html" title="25.5.13 ndb_import — Import CSV Data Into NDB">
Section 25.5.13, “ndb_import — Import CSV Data Into NDB”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-variables.html" title="19.5.1.39 Replication and Variables">
Section 19.5.1.39, “Replication and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-source.html" title="19.1.6.2 Replication Source Options and Variables">
Section 19.1.6.2, “Replication Source Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="example-auto-increment.html" title="5.6.9 Using AUTO_INCREMENT">
Section 5.6.9, “Using AUTO_INCREMENT”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
auto_increment_offset
</h3>
<dl>
<dt>
<a class="xref" href="innodb-auto-increment-handling.html" title="17.6.1.6 AUTO_INCREMENT Handling in InnoDB">
Section 17.6.1.6, “AUTO_INCREMENT Handling in InnoDB”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-frequently-asked-questions.html" title="20.10 Frequently Asked Questions">
Section 20.10, “Frequently Asked Questions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log-mixed.html" title="7.4.4.3 Mixed Binary Logging Format">
Section 7.4.4.3, “Mixed Binary Logging Format”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="faqs-general.html" title="A.1 MySQL 8.4 FAQ: General">
Section A.1, “MySQL 8.4 FAQ: General”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-programs-ndb-import.html" title="25.5.13 ndb_import — Import CSV Data Into NDB">
Section 25.5.13, “ndb_import — Import CSV Data Into NDB”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-variables.html" title="19.5.1.39 Replication and Variables">
Section 19.5.1.39, “Replication and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-source.html" title="19.1.6.2 Replication Source Options and Variables">
Section 19.1.6.2, “Replication Source Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="example-auto-increment.html" title="5.6.9 Using AUTO_INCREMENT">
Section 5.6.9, “Using AUTO_INCREMENT”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
AUTOCOMMIT
</h3>
<dl>
<dt>
<a class="xref" href="replication-features-transactions.html" title="19.5.1.35 Replication and Transactions">
Section 19.5.1.35, “Replication and Transactions”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
autocommit
</h3>
<dl>
<dt>
<a class="xref" href="alter-tablespace.html" title="15.1.10 ALTER TABLESPACE Statement">
Section 15.1.10, “ALTER TABLESPACE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-autocommit-commit-rollback.html" title="17.7.2.2 autocommit, Commit, and Rollback">
Section 17.7.2.2, “autocommit, Commit, and Rollback”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="converting-tables-to-innodb.html" title="17.6.1.5 Converting Tables from MyISAM to InnoDB">
Section 17.6.1.5, “Converting Tables from MyISAM to InnoDB”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-deadlock-detection.html" title="17.7.5.2 Deadlock Detection">
Section 17.7.5.2, “Deadlock Detection”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="delete.html" title="15.2.2 DELETE Statement">
Section 15.2.2, “DELETE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="general-tablespaces.html" title="17.6.3.3 General Tablespaces">
Section 17.6.3.3, “General Tablespaces”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-acid.html" title="17.2 InnoDB and the ACID Model">
Section 17.2, “InnoDB and the ACID Model”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-locking-transaction-model.html" title="17.7 InnoDB Locking and Transaction Model">
Section 17.7, “InnoDB Locking and Transaction Model”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="lock-tables.html" title="15.3.6 LOCK TABLES and UNLOCK TABLES Statements">
Section 15.3.6, “LOCK TABLES and UNLOCK TABLES Statements”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-locking-reads.html" title="17.7.2.4 Locking Reads">
Section 17.7.2.4, “Locking Reads”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-locks-set.html" title="17.7.3 Locks Set by Different SQL Statements in InnoDB">
Section 17.7.3, “Locks Set by Different SQL Statements in InnoDB”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-migration.html" title="17.6.1.4 Moving or Copying InnoDB Tables">
Section 17.6.1.4, “Moving or Copying InnoDB Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-performance-ro-txn.html" title="10.5.3 Optimizing InnoDB Read-Only Transactions">
Section 10.5.3, “Optimizing InnoDB Read-Only Transactions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-transaction-tables.html" title="29.12.7 Performance Schema Transaction Tables">
Section 29.12.7, “Performance Schema Transaction Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-purge-configuration.html" title="17.8.9 Purge Configuration">
Section 17.8.9, “Purge Configuration”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-temptables.html" title="19.5.1.31 Replication and Temporary Tables">
Section 19.5.1.31, “Replication and Temporary Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-transactions.html" title="19.5.1.35 Replication and Transactions">
Section 19.5.1.35, “Replication and Transactions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-gtids-restrictions.html" title="19.1.3.7 Restrictions on Replication with GTIDs">
Section 19.1.3.7, “Restrictions on Replication with GTIDs”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="commit.html" title="15.3.1 START TRANSACTION, COMMIT, and ROLLBACK Statements">
Section 15.3.1, “START TRANSACTION, COMMIT, and ROLLBACK Statements”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-innodb-trx-table.html" title="28.4.28 The INFORMATION_SCHEMA INNODB_TRX Table">
Section 28.4.28, “The INFORMATION_SCHEMA INNODB_TRX Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="thread-pool-operation.html" title="7.6.3.3 Thread Pool Operation">
Section 7.6.3.3, “Thread Pool Operation”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-transaction-isolation-levels.html" title="17.7.2.1 Transaction Isolation Levels">
Section 17.7.2.1, “Transaction Isolation Levels”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
automatic_sp_privileges
</h3>
<dl>
<dt>
<a class="xref" href="alter-procedure.html" title="15.1.7 ALTER PROCEDURE Statement">
Section 15.1.7, “ALTER PROCEDURE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="create-procedure.html" title="15.1.17 CREATE PROCEDURE and CREATE FUNCTION Statements">
Section 15.1.17, “CREATE PROCEDURE and CREATE FUNCTION Statements”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="drop-procedure.html" title="15.1.29 DROP PROCEDURE and DROP FUNCTION Statements">
Section 15.1.29, “DROP PROCEDURE and DROP FUNCTION Statements”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-options.html" title="7.1.7 Server Command Options">
Section 7.1.7, “Server Command Options”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="stored-routines-privileges.html" title="27.2.2 Stored Routines and MySQL Privileges">
Section 27.2.2, “Stored Routines and MySQL Privileges”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<a name="sysvar-index-B">
</a>
<h3 class="title">
B
</h3>
<p>
[
<a class="link" href="dynindex-sysvar.html#sysvar-index-top">
index top
</a>
]
</p>
<dl>
<dt>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
back_log
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
basedir
</h3>
<dl>
<dt>
<a class="xref" href="install-plugin.html" title="15.7.4.4 INSTALL PLUGIN Statement">
Section 15.7.4.4, “INSTALL PLUGIN Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="macos-installation-launchd.html" title="2.4.3 Installing and Using the MySQL Launch Daemon">
Section 2.4.3, “Installing and Using the MySQL Launch Daemon”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-options.html" title="7.1.7 Server Command Options">
Section 7.1.7, “Server Command Options”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
big_tables
</h3>
<dl>
<dt>
<a class="xref" href="internal-temporary-tables.html" title="10.4.4 Internal Temporary Table Use in MySQL">
Section 10.4.4, “Internal Temporary Table Use in MySQL”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
bind_address
</h3>
<dl>
<dt>
<a class="xref" href="can-not-connect-to-server.html" title="B.3.2.2 Can't connect to [local] MySQL server">
Section B.3.2.2, “Can't connect to [local] MySQL server”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-connection-security.html" title="20.6.1 Communication Stack for Connection Security Management">
Section 20.6.1, “Communication Stack for Connection Security Management”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="ipv6-server-config.html" title="7.1.13.2 Configuring the MySQL Server to Permit IPv6 Connections">
Section 7.1.13.2, “Configuring the MySQL Server to Permit IPv6 Connections”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="ipv6-remote-connections.html" title="7.1.13.4 Connecting Using IPv6 Nonlocal Host Addresses">
Section 7.1.13.4, “Connecting Using IPv6 Nonlocal Host Addresses”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="ipv6-local-connections.html" title="7.1.13.3 Connecting Using the IPv6 Local Host Address">
Section 7.1.13.3, “Connecting Using the IPv6 Local Host Address”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-ip-address-permissions.html" title="20.6.4 Group Replication IP Address Permissions">
Section 20.6.4, “Group Replication IP Address Permissions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="ipv6-support.html" title="7.1.13 IPv6 Support">
Section 7.1.13, “IPv6 Support”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysqld-multi.html" title="6.3.4 mysqld_multi — Manage Multiple MySQL Servers">
Section 6.3.4, “mysqld_multi — Manage Multiple MySQL Servers”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="network-namespace-support.html" title="7.1.14 Network Namespace Support">
Section 7.1.14, “Network Namespace Support”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="nonpersistible-system-variables.html" title="7.1.9.4 Nonpersistible and Persist-Restricted System Variables">
Section 7.1.9.4, “Nonpersistible and Persist-Restricted System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="ipv6-brokers.html" title="7.1.13.5 Obtaining an IPv6 Address from a Broker">
Section 7.1.13.5, “Obtaining an IPv6 Address from a Broker”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="multiple-servers.html" title="7.8 Running Multiple MySQL Instances on One Machine">
Section 7.8, “Running Multiple MySQL Instances on One Machine”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-distributed-recovery-connections.html#group-replication-distributed-recovery-connections-endpoints" title="20.5.4.1.1 Selecting addresses for distributed recovery endpoints">
Section 20.5.4.1.1, “Selecting addresses for distributed recovery endpoints”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-ipv6.html" title="20.5.5 Support For IPv6 And For Mixed IPv6 And IPv4 Groups">
Section 20.5.5, “Support For IPv6 And For Mixed IPv6 And IPv4 Groups”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-ndbinfo-processes.html" title="25.6.17.51 The ndbinfo processes Table">
Section 25.6.17.51, “The ndbinfo processes Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="problems-connecting.html" title="8.2.22 Troubleshooting Problems Connecting to MySQL">
Section 8.2.22, “Troubleshooting Problems Connecting to MySQL”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="x-plugin-options-system-variables.html" title="22.5.6.2 X Plugin Options and System Variables">
Section 22.5.6.2, “X Plugin Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
binlog
</h3>
<dl>
<dt>
<a class="xref" href="mysqlbinlog.html" title="6.6.9 mysqlbinlog — Utility for Processing Binary Log Files">
Section 6.6.9, “mysqlbinlog — Utility for Processing Binary Log Files”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
binlog_cache_size
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-binary-log.html" title="19.1.6.4 Binary Logging Options and Variables">
Section 19.1.6.4, “Binary Logging Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-status-variables.html" title="7.1.10 Server Status Variables">
Section 7.1.10, “Server Status Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log.html" title="7.4.4 The Binary Log">
Section 7.4.4, “The Binary Log”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-what-is-new.html" title="25.2.4 What is New in MySQL NDB Cluster 8.4">
Section 25.2.4, “What is New in MySQL NDB Cluster 8.4”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
binlog_checksum
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-binary-log.html" title="19.1.6.4 Binary Logging Options and Variables">
Section 19.1.6.4, “Binary Logging Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-limitations.html" title="20.3.2 Group Replication Limitations">
Section 20.3.2, “Group Replication Limitations”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="glossary.html" title="MySQL Glossary">
MySQL Glossary
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-transactions.html" title="19.5.1.35 Replication and Transactions">
Section 19.5.1.35, “Replication and Transactions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log.html" title="7.4.4 The Binary Log">
Section 7.4.4, “The Binary Log”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
binlog_direct_non_transactional_updates
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-binary-log.html" title="19.1.6.4 Binary Logging Options and Variables">
Section 19.1.6.4, “Binary Logging Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-transactions.html" title="19.5.1.35 Replication and Transactions">
Section 19.5.1.35, “Replication and Transactions”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
binlog_encryption
</h3>
<dl>
<dt>
<a class="xref" href="alter-instance.html" title="15.1.5 ALTER INSTANCE Statement">
Section 15.1.5, “ALTER INSTANCE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-binlog-encryption-key-rotation.html" title="19.3.2.3 Binary Log Master Key Rotation">
Section 19.3.2.3, “Binary Log Master Key Rotation”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-binary-log.html" title="19.1.6.4 Binary Logging Options and Variables">
Section 19.1.6.4, “Binary Logging Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-binlog-encryption.html" title="19.3.2 Encrypting Binary Log Files and Relay Log Files">
Section 19.3.2, “Encrypting Binary Log Files and Relay Log Files”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="security-against-attack.html" title="8.1.3 Making MySQL Secure Against Attackers">
Section 8.1.3, “Making MySQL Secure Against Attackers”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysqlbinlog.html" title="6.6.9 mysqlbinlog — Utility for Processing Binary Log Files">
Section 6.6.9, “mysqlbinlog — Utility for Processing Binary Log Files”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="privileges-provided.html" title="8.2.2 Privileges Provided by MySQL">
Section 8.2.2, “Privileges Provided by MySQL”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-security.html" title="19.3 Replication Security">
Section 19.3, “Replication Security”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="show-binary-logs.html" title="15.7.7.2 SHOW BINARY LOGS Statement">
Section 15.7.7.2, “SHOW BINARY LOGS Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log.html" title="7.4.4 The Binary Log">
Section 7.4.4, “The Binary Log”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
binlog_error_action
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-binary-log.html" title="19.1.6.4 Binary Logging Options and Variables">
Section 19.1.6.4, “Binary Logging Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-gtids-concepts.html" title="19.1.3.1 GTID Format and Storage">
Section 19.1.3.1, “GTID Format and Storage”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log.html" title="7.4.4 The Binary Log">
Section 7.4.4, “The Binary Log”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
binlog_expire_logs_auto_purge
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-binary-log.html" title="19.1.6.4 Binary Logging Options and Variables">
Section 19.1.6.4, “Binary Logging Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
binlog_expire_logs_seconds
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-binary-log.html" title="19.1.6.4 Binary Logging Options and Variables">
Section 19.1.6.4, “Binary Logging Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-gtids-auto-positioning.html" title="19.1.3.3 GTID Auto-Positioning">
Section 19.1.3.3, “GTID Auto-Positioning”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="purge-binary-logs.html" title="15.4.1.1 PURGE BINARY LOGS Statement">
Section 15.4.1.1, “PURGE BINARY LOGS Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="log-file-maintenance.html" title="7.4.6 Server Log Maintenance">
Section 7.4.6, “Server Log Maintenance”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
binlog_format
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-binary-log.html" title="19.1.6.4 Binary Logging Options and Variables">
Section 19.1.6.4, “Binary Logging Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="data-type-defaults.html" title="13.6 Data Type Default Values">
Section 13.6, “Data Type Default Values”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="date-and-time-functions.html" title="14.7 Date and Time Functions">
Section 14.7, “Date and Time Functions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-rbr-safe-unsafe.html" title="19.2.1.3 Determination of Safe and Unsafe Statements in Binary Logging">
Section 19.2.1.3, “Determination of Safe and Unsafe Statements in Binary Logging”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-rules-db-options.html" title="19.2.5.1 Evaluation of Database-Level Replication and Binary Logging Options">
Section 19.2.5.1, “Evaluation of Database-Level Replication and Binary Logging Options”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-rules-table-options.html" title="19.2.5.2 Evaluation of Table-Level Replication Options">
Section 19.2.5.2, “Evaluation of Table-Level Replication Options”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="grant-tables.html" title="8.2.3 Grant Tables">
Section 8.2.3, “Grant Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-requirements.html" title="20.3.1 Group Replication Requirements">
Section 20.3.1, “Group Replication Requirements”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-gtids-lifecycle.html" title="19.1.3.2 GTID Life Cycle">
Section 19.1.3.2, “GTID Life Cycle”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-functions.html" title="14.15 Information Functions">
Section 14.15, “Information Functions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-rules-examples.html" title="19.2.5.3 Interactions Between Replication Filtering Options">
Section 19.2.5.3, “Interactions Between Replication Filtering Options”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="load-data.html" title="15.2.9 LOAD DATA Statement">
Section 15.2.9, “LOAD DATA Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="locking-functions.html" title="14.14 Locking Functions">
Section 14.14, “Locking Functions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log-mysql-database.html" title="7.4.4.4 Logging Format for Changes to mysql Database Tables">
Section 7.4.4.4, “Logging Format for Changes to mysql Database Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mathematical-functions.html" title="14.6.2 Mathematical Functions">
Section 14.6.2, “Mathematical Functions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="miscellaneous-functions.html" title="14.23 Miscellaneous Functions">
Section 14.23, “Miscellaneous Functions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log-mixed.html" title="7.4.4.3 Mixed Binary Logging Format">
Section 7.4.4.3, “Mixed Binary Logging Format”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="faqs-replication.html" title="A.14 MySQL 8.4 FAQ: Replication">
Section A.14, “MySQL 8.4 FAQ: Replication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysqlbinlog.html" title="6.6.9 mysqlbinlog — Utility for Processing Binary Log Files">
Section 6.6.9, “mysqlbinlog — Utility for Processing Binary Log Files”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="partitioning-info.html" title="26.3.5 Obtaining Information About Partitions">
Section 26.3.5, “Obtaining Information About Partitions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-functions-synchronization.html" title="14.18.4 Position-Based Synchronization Functions">
Section 14.18.4, “Position-Based Synchronization Functions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-privilege-checks-account.html" title="19.3.3.1 Privileges For The Replication PRIVILEGE_CHECKS_USER Account">
Section 19.3.3.1, “Privileges For The Replication PRIVILEGE_CHECKS_USER Account”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="privileges-provided.html" title="8.2.2 Privileges Provided by MySQL">
Section 8.2.2, “Privileges Provided by MySQL”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-blackhole.html" title="19.5.1.2 Replication and BLACKHOLE Tables">
Section 19.5.1.2, “Replication and BLACKHOLE Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-load-data.html" title="19.5.1.19 Replication and LOAD DATA">
Section 19.5.1.19, “Replication and LOAD DATA”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-memory.html" title="19.5.1.21 Replication and MEMORY Tables">
Section 19.5.1.21, “Replication and MEMORY Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-temptables.html" title="19.5.1.31 Replication and Temporary Tables">
Section 19.5.1.31, “Replication and Temporary Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-transactions.html" title="19.5.1.35 Replication and Transactions">
Section 19.5.1.35, “Replication and Transactions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-formats.html" title="19.2.1 Replication Formats">
Section 19.2.1, “Replication Formats”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-mysqldb.html" title="19.5.1.22 Replication of the mysql System Schema">
Section 19.5.1.22, “Replication of the mysql System Schema”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-privilege-checks.html" title="19.3.3 Replication Privilege Checks">
Section 19.3.3, “Replication Privilege Checks”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-gtids-restrictions.html" title="19.1.3.7 Restrictions on Replication with GTIDs">
Section 19.1.3.7, “Restrictions on Replication with GTIDs”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="xa-restrictions.html" title="15.3.8.3 Restrictions on XA Transactions">
Section 15.3.8.3, “Restrictions on XA Transactions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-binlog-encryption-scope.html" title="19.3.2.1 Scope of Binary Log Encryption">
Section 19.3.2.1, “Scope of Binary Log Encryption”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log-setting.html" title="7.4.4.2 Setting The Binary Log Format">
Section 7.4.4.2, “Setting The Binary Log Format”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="stored-programs-logging.html" title="27.7 Stored Program Binary Logging">
Section 27.7, “Stored Program Binary Logging”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="system-variable-privileges.html" title="7.1.9.1 System Variable Privileges">
Section 7.1.9.1, “System Variable Privileges”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="blackhole-storage-engine.html" title="18.6 The BLACKHOLE Storage Engine">
Section 18.6, “The BLACKHOLE Storage Engine”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="query-log.html" title="7.4.3 The General Query Log">
Section 7.4.3, “The General Query Log”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="slow-query-log.html" title="7.4.5 The Slow Query Log">
Section 7.4.5, “The Slow Query Log”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-transaction-isolation-levels.html" title="17.7.2.1 Transaction Isolation Levels">
Section 17.7.2.1, “Transaction Isolation Levels”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-rbr-usage.html" title="19.2.1.2 Usage of Row-Based Logging and Replication">
Section 19.2.1.2, “Usage of Row-Based Logging and Replication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
binlog_group_commit_sync_delay
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-binary-log.html" title="19.1.6.4 Binary Logging Options and Variables">
Section 19.1.6.4, “Binary Logging Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
binlog_group_commit_sync_no_delay_count
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-binary-log.html" title="19.1.6.4 Binary Logging Options and Variables">
Section 19.1.6.4, “Binary Logging Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
binlog_gtid_simple_recovery
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-gtids.html" title="19.1.6.5 Global Transaction ID System Variables">
Section 19.1.6.5, “Global Transaction ID System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
binlog_max_flush_queue_time
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-binary-log.html" title="19.1.6.4 Binary Logging Options and Variables">
Section 19.1.6.4, “Binary Logging Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
binlog_order_commits
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-binary-log.html" title="19.1.6.4 Binary Logging Options and Variables">
Section 19.1.6.4, “Binary Logging Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
binlog_rotate_encryption_master_key_at_startup
</h3>
<dl>
<dt>
<a class="xref" href="replication-binlog-encryption-key-rotation.html" title="19.3.2.3 Binary Log Master Key Rotation">
Section 19.3.2.3, “Binary Log Master Key Rotation”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-binary-log.html" title="19.1.6.4 Binary Logging Options and Variables">
Section 19.1.6.4, “Binary Logging Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="privileges-provided.html" title="8.2.2 Privileges Provided by MySQL">
Section 8.2.2, “Privileges Provided by MySQL”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
binlog_row_event_max_size
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-binary-log.html" title="19.1.6.4 Binary Logging Options and Variables">
Section 19.1.6.4, “Binary Logging Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log-setting.html" title="7.4.4.2 Setting The Binary Log Format">
Section 7.4.4.2, “Setting The Binary Log Format”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
binlog_row_image
</h3>
<dl>
<dt>
<a class="xref" href="replication-sbr-rbr.html" title="19.2.1.1 Advantages and Disadvantages of Statement-Based and Row-Based Replication">
Section 19.2.1.1, “Advantages and Disadvantages of Statement-Based and Row-Based
Replication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-binary-log.html" title="19.1.6.4 Binary Logging Options and Variables">
Section 19.1.6.4, “Binary Logging Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="invisible-columns.html" title="15.1.20.10 Invisible Columns">
Section 15.1.20.10, “Invisible Columns”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="optimizing-innodb-diskio.html" title="10.5.8 Optimizing InnoDB Disk I/O">
Section 10.5.8, “Optimizing InnoDB Disk I/O”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
binlog_row_metadata
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-binary-log.html" title="19.1.6.4 Binary Logging Options and Variables">
Section 19.1.6.4, “Binary Logging Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
binlog_row_value_options
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-binary-log.html" title="19.1.6.4 Binary Logging Options and Variables">
Section 19.1.6.4, “Binary Logging Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-json.html" title="19.5.1.17 Replication of JSON Documents">
Section 19.5.1.17, “Replication of JSON Documents”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="json.html" title="13.5 The JSON Data Type">
Section 13.5, “The JSON Data Type”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
binlog_rows_query_log_events
</h3>
<dl>
<dt>
<a class="xref" href="replication-sbr-rbr.html" title="19.2.1.1 Advantages and Disadvantages of Statement-Based and Row-Based Replication">
Section 19.2.1.1, “Advantages and Disadvantages of Statement-Based and Row-Based
Replication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-solutions-rbr-monitoring.html" title="19.4.3 Monitoring Row-based Replication">
Section 19.4.3, “Monitoring Row-based Replication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysqlbinlog-row-events.html" title="6.6.9.2 mysqlbinlog Row Event Display">
Section 6.6.9.2, “mysqlbinlog Row Event Display”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysqlbinlog.html" title="6.6.9 mysqlbinlog — Utility for Processing Binary Log Files">
Section 6.6.9, “mysqlbinlog — Utility for Processing Binary Log Files”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
binlog_stmt_cache_size
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-binary-log.html" title="19.1.6.4 Binary Logging Options and Variables">
Section 19.1.6.4, “Binary Logging Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-status-variables.html" title="7.1.10 Server Status Variables">
Section 7.1.10, “Server Status Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
binlog_transaction_compression
</h3>
<dl>
<dt>
<a class="xref" href="binary-log-transaction-compression.html" title="7.4.4.5 Binary Log Transaction Compression">
Section 7.4.4.5, “Binary Log Transaction Compression”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-binary-log.html" title="19.1.6.4 Binary Logging Options and Variables">
Section 19.1.6.4, “Binary Logging Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="change-replication-source-to.html" title="15.4.2.2 CHANGE REPLICATION SOURCE TO Statement">
Section 15.4.2.2, “CHANGE REPLICATION SOURCE TO Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log-transaction-compression.html#binary-log-transaction-compression-uncompressed" title="7.4.4.5.2 Combining Compressed and Uncompressed Transaction Payloads">
Section 7.4.4.5.2, “Combining Compressed and Uncompressed Transaction Payloads”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-message-compression.html" title="20.7.4 Message Compression">
Section 20.7.4, “Message Compression”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysqlbinlog.html" title="6.6.9 mysqlbinlog — Utility for Processing Binary Log Files">
Section 6.6.9, “mysqlbinlog — Utility for Processing Binary Log Files”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-binary-log-transaction-compression-stats-table.html" title="29.12.11.1 The binary_log_transaction_compression_stats Table">
Section 29.12.11.1, “The binary_log_transaction_compression_stats Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
binlog_transaction_compression_level_zstd
</h3>
<dl>
<dt>
<a class="xref" href="binary-log-transaction-compression.html" title="7.4.4.5 Binary Log Transaction Compression">
Section 7.4.4.5, “Binary Log Transaction Compression”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-binary-log.html" title="19.1.6.4 Binary Logging Options and Variables">
Section 19.1.6.4, “Binary Logging Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
binlog_transaction_dependency_history_size
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-binary-log.html" title="19.1.6.4 Binary Logging Options and Variables">
Section 19.1.6.4, “Binary Logging Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="memory-use.html" title="10.12.3.1 How MySQL Uses Memory">
Section 10.12.3.1, “How MySQL Uses Memory”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-replication-mta.html" title="25.7.11 NDB Cluster Replication Using the Multithreaded Applier">
Section 25.7.11, “NDB Cluster Replication Using the Multithreaded Applier”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
block_encryption_mode
</h3>
<dl>
<dt>
<a class="xref" href="encryption-functions.html" title="14.13 Encryption and Compression Functions">
Section 14.13, “Encryption and Compression Functions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
build_id
</h3>
<dl>
<dt>
<a class="xref" href="source-configuration-options.html" title="2.8.7 MySQL Source-Configuration Options">
Section 2.8.7, “MySQL Source-Configuration Options”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
bulk_insert_buffer_size
</h3>
<dl>
<dt>
<a class="xref" href="myisam-start.html" title="18.2.1 MyISAM Startup Options">
Section 18.2.1, “MyISAM Startup Options”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="insert-optimization.html" title="10.2.5.1 Optimizing INSERT Statements">
Section 10.2.5.1, “Optimizing INSERT Statements”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<a name="sysvar-index-C">
</a>
<h3 class="title">
C
</h3>
<p>
[
<a class="link" href="dynindex-sysvar.html#sysvar-index-top">
index top
</a>
]
</p>
<dl>
<dt>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
caching_sha
</h3>
<dl>
<dt>
<a class="xref" href="caching-sha2-pluggable-authentication.html" title="8.4.1.2 Caching SHA-2 Pluggable Authentication">
Section 8.4.1.2, “Caching SHA-2 Pluggable Authentication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="creating-ssl-rsa-files-using-mysql.html" title="8.3.3.1 Creating SSL and RSA Certificates and Keys using MySQL">
Section 8.3.3.1, “Creating SSL and RSA Certificates and Keys using MySQL”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-status-variables.html" title="7.1.10 Server Status Variables">
Section 7.1.10, “Server Status Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
character_set_client
</h3>
<dl>
<dt>
<a class="xref" href="charset-configuration.html" title="12.15 Character Set Configuration">
Section 12.15, “Character Set Configuration”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="charset-connection.html" title="12.4 Connection Character Sets and Collations">
Section 12.4, “Connection Character Sets and Collations”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="load-data.html" title="15.2.9 LOAD DATA Statement">
Section 15.2.9, “LOAD DATA Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log-mixed.html" title="7.4.4.3 Mixed Binary Logging Format">
Section 7.4.4.3, “Mixed Binary Logging Format”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="faqs-cjk.html" title="A.11 MySQL 8.4 FAQ: MySQL Chinese, Japanese, and Korean Character Sets">
Section A.11, “MySQL 8.4 FAQ: MySQL Chinese, Japanese, and Korean
Character Sets”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="query-attributes.html" title="11.6 Query Attributes">
Section 11.6, “Query Attributes”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-variables.html" title="19.5.1.39 Replication and Variables">
Section 19.5.1.39, “Replication and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="set-character-set.html" title="15.7.6.2 SET CHARACTER SET Statement">
Section 15.7.6.2, “SET CHARACTER SET Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="set-names.html" title="15.7.6.3 SET NAMES Statement">
Section 15.7.6.3, “SET NAMES Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="show-create-event.html" title="15.7.7.8 SHOW CREATE EVENT Statement">
Section 15.7.7.8, “SHOW CREATE EVENT Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="show-create-procedure.html" title="15.7.7.10 SHOW CREATE PROCEDURE Statement">
Section 15.7.7.10, “SHOW CREATE PROCEDURE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="show-create-trigger.html" title="15.7.7.12 SHOW CREATE TRIGGER Statement">
Section 15.7.7.12, “SHOW CREATE TRIGGER Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="show-create-view.html" title="15.7.7.14 SHOW CREATE VIEW Statement">
Section 15.7.7.14, “SHOW CREATE VIEW Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="show-events.html" title="15.7.7.19 SHOW EVENTS Statement">
Section 15.7.7.19, “SHOW EVENTS Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="show-procedure-status.html" title="15.7.7.30 SHOW PROCEDURE STATUS Statement">
Section 15.7.7.30, “SHOW PROCEDURE STATUS Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="show-triggers.html" title="15.7.7.40 SHOW TRIGGERS Statement">
Section 15.7.7.40, “SHOW TRIGGERS Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log.html" title="7.4.4 The Binary Log">
Section 7.4.4, “The Binary Log”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-events-table.html" title="28.3.14 The INFORMATION_SCHEMA EVENTS Table">
Section 28.3.14, “The INFORMATION_SCHEMA EVENTS Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-routines-table.html" title="28.3.30 The INFORMATION_SCHEMA ROUTINES Table">
Section 28.3.30, “The INFORMATION_SCHEMA ROUTINES Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-triggers-table.html" title="28.3.44 The INFORMATION_SCHEMA TRIGGERS Table">
Section 28.3.44, “The INFORMATION_SCHEMA TRIGGERS Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-views-table.html" title="28.3.47 The INFORMATION_SCHEMA VIEWS Table">
Section 28.3.47, “The INFORMATION_SCHEMA VIEWS Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="rewriter-query-rewrite-plugin-usage.html" title="7.6.4.2 Using the Rewriter Query Rewrite Plugin">
Section 7.6.4.2, “Using the Rewriter Query Rewrite Plugin”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
character_set_connection
</h3>
<dl>
<dt>
<a class="xref" href="cast-functions.html" title="14.10 Cast Functions and Operators">
Section 14.10, “Cast Functions and Operators”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="string-functions-charset.html" title="14.8.3 Character Set and Collation of Function Results">
Section 14.8.3, “Character Set and Collation of Function Results”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="charset-introducer.html" title="12.3.8 Character Set Introducers">
Section 12.3.8, “Character Set Introducers”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="charset-repertoire.html" title="12.2.1 Character Set Repertoire">
Section 12.2.1, “Character Set Repertoire”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="charset-literal.html" title="12.3.6 Character String Literal Character Set and Collation">
Section 12.3.6, “Character String Literal Character Set and Collation”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="charset-collation-coercibility.html" title="12.8.4 Collation Coercibility in Expressions">
Section 12.8.4, “Collation Coercibility in Expressions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="charset-connection.html" title="12.4 Connection Character Sets and Collations">
Section 12.4, “Connection Character Sets and Collations”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="date-and-time-functions.html" title="14.7 Date and Time Functions">
Section 14.7, “Date and Time Functions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="encryption-functions.html" title="14.13 Encryption and Compression Functions">
Section 14.13, “Encryption and Compression Functions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log-mixed.html" title="7.4.4.3 Mixed Binary Logging Format">
Section 7.4.4.3, “Mixed Binary Logging Format”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="faqs-cjk.html" title="A.11 MySQL 8.4 FAQ: MySQL Chinese, Japanese, and Korean Character Sets">
Section A.11, “MySQL 8.4 FAQ: MySQL Chinese, Japanese, and Korean
Character Sets”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="locale-support.html" title="12.16 MySQL Server Locale Support">
Section 12.16, “MySQL Server Locale Support”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-variables.html" title="19.5.1.39 Replication and Variables">
Section 19.5.1.39, “Replication and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="set-character-set.html" title="15.7.6.2 SET CHARACTER SET Statement">
Section 15.7.6.2, “SET CHARACTER SET Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="set-names.html" title="15.7.6.3 SET NAMES Statement">
Section 15.7.6.3, “SET NAMES Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="string-literals.html" title="11.1.1 String Literals">
Section 11.1.1, “String Literals”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="type-conversion.html" title="14.3 Type Conversion in Expression Evaluation">
Section 14.3, “Type Conversion in Expression Evaluation”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
character_set_database
</h3>
<dl>
<dt>
<a class="xref" href="alter-table.html" title="15.1.9 ALTER TABLE Statement">
Section 15.1.9, “ALTER TABLE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="charset-connection.html" title="12.4 Connection Character Sets and Collations">
Section 12.4, “Connection Character Sets and Collations”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="create-procedure.html" title="15.1.17 CREATE PROCEDURE and CREATE FUNCTION Statements">
Section 15.1.17, “CREATE PROCEDURE and CREATE FUNCTION Statements”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="charset-database.html" title="12.3.3 Database Character Set and Collation">
Section 12.3.3, “Database Character Set and Collation”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="load-data.html" title="15.2.9 LOAD DATA Statement">
Section 15.2.9, “LOAD DATA Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log-mixed.html" title="7.4.4.3 Mixed Binary Logging Format">
Section 7.4.4.3, “Mixed Binary Logging Format”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-variables.html" title="19.5.1.39 Replication and Variables">
Section 19.5.1.39, “Replication and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="set-character-set.html" title="15.7.6.2 SET CHARACTER SET Statement">
Section 15.7.6.2, “SET CHARACTER SET Statement”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
character_set_filesystem
</h3>
<dl>
<dt>
<a class="xref" href="load-data.html" title="15.2.9 LOAD DATA Statement">
Section 15.2.9, “LOAD DATA Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="select-into.html" title="15.2.13.1 SELECT ... INTO Statement">
Section 15.2.13.1, “SELECT ... INTO Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="string-functions.html" title="14.8 String Functions and Operators">
Section 14.8, “String Functions and Operators”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
character_set_results
</h3>
<dl>
<dt>
<a class="xref" href="charset-connection.html" title="12.4 Connection Character Sets and Collations">
Section 12.4, “Connection Character Sets and Collations”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="charset-errors.html" title="12.6 Error Message Character Set">
Section 12.6, “Error Message Character Set”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="faqs-cjk.html" title="A.11 MySQL 8.4 FAQ: MySQL Chinese, Japanese, and Korean Character Sets">
Section A.11, “MySQL 8.4 FAQ: MySQL Chinese, Japanese, and Korean
Character Sets”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="set-character-set.html" title="15.7.6.2 SET CHARACTER SET Statement">
Section 15.7.6.2, “SET CHARACTER SET Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="set-names.html" title="15.7.6.3 SET NAMES Statement">
Section 15.7.6.3, “SET NAMES Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="charset-metadata.html" title="12.2.2 UTF-8 for Metadata">
Section 12.2.2, “UTF-8 for Metadata”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
character_set_server
</h3>
<dl>
<dt>
<a class="xref" href="charset-configuration.html" title="12.15 Character Set Configuration">
Section 12.15, “Character Set Configuration”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="charset-connection.html" title="12.4 Connection Character Sets and Collations">
Section 12.4, “Connection Character Sets and Collations”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="charset-database.html" title="12.3.3 Database Character Set and Collation">
Section 12.3.3, “Database Character Set and Collation”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="fulltext-stopwords.html" title="14.9.4 Full-Text Stopwords">
Section 14.9.4, “Full-Text Stopwords”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log-mixed.html" title="7.4.4.3 Mixed Binary Logging Format">
Section 7.4.4.3, “Mixed Binary Logging Format”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-charset.html" title="19.5.1.3 Replication and Character Sets">
Section 19.5.1.3, “Replication and Character Sets”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-variables.html" title="19.5.1.39 Replication and Variables">
Section 19.5.1.39, “Replication and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="charset-server.html" title="12.3.2 Server Character Set and Collation">
Section 12.3.2, “Server Character Set and Collation”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
character_set_system
</h3>
<dl>
<dt>
<a class="xref" href="charset-configuration.html" title="12.15 Character Set Configuration">
Section 12.15, “Character Set Configuration”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="charset-metadata.html" title="12.2.2 UTF-8 for Metadata">
Section 12.2.2, “UTF-8 for Metadata”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
character_sets_dir
</h3>
<dl>
<dt>
<a class="xref" href="adding-collation-simple-8bit.html" title="12.14.3 Adding a Simple Collation to an 8-Bit Character Set">
Section 12.14.3, “Adding a Simple Collation to an 8-Bit Character Set”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="ldml-collation-example.html" title="12.14.4.1 Defining a UCA Collation Using LDML Syntax">
Section 12.14.4.1, “Defining a UCA Collation Using LDML Syntax”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
check_proxy_users
</h3>
<dl>
<dt>
<a class="xref" href="proxy-users.html" title="8.2.19 Proxy Users">
Section 8.2.19, “Proxy Users”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
clone_autotune_concurrency
</h3>
<dl>
<dt>
<a class="xref" href="clone-plugin-options-variables.html" title="7.6.7.13 Clone System Variables">
Section 7.6.7.13, “Clone System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="clone-plugin-monitoring.html" title="7.6.7.10 Monitoring Cloning Operations">
Section 7.6.7.10, “Monitoring Cloning Operations”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
clone_block_ddl
</h3>
<dl>
<dt>
<a class="xref" href="clone-plugin-options-variables.html" title="7.6.7.13 Clone System Variables">
Section 7.6.7.13, “Clone System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="clone-plugin-concurrent-ddl.html" title="7.6.7.4 Cloning and Concurrent DDL">
Section 7.6.7.4, “Cloning and Concurrent DDL”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="clone-plugin-failure-handling.html" title="7.6.7.9 Remote Cloning Operation Failure Handling">
Section 7.6.7.9, “Remote Cloning Operation Failure Handling”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
clone_buffer_size
</h3>
<dl>
<dt>
<a class="xref" href="clone-plugin-options-variables.html" title="7.6.7.13 Clone System Variables">
Section 7.6.7.13, “Clone System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
clone_ddl_timeout
</h3>
<dl>
<dt>
<a class="xref" href="clone-plugin-options-variables.html" title="7.6.7.13 Clone System Variables">
Section 7.6.7.13, “Clone System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="clone-plugin-failure-handling.html" title="7.6.7.9 Remote Cloning Operation Failure Handling">
Section 7.6.7.9, “Remote Cloning Operation Failure Handling”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
clone_delay_after_data_drop
</h3>
<dl>
<dt>
<a class="xref" href="clone-plugin-options-variables.html" title="7.6.7.13 Clone System Variables">
Section 7.6.7.13, “Clone System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
clone_donor_timeout_after_network_failure
</h3>
<dl>
<dt>
<a class="xref" href="clone-plugin-options-variables.html" title="7.6.7.13 Clone System Variables">
Section 7.6.7.13, “Clone System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="clone-plugin-failure-handling.html" title="7.6.7.9 Remote Cloning Operation Failure Handling">
Section 7.6.7.9, “Remote Cloning Operation Failure Handling”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
clone_enable_compression
</h3>
<dl>
<dt>
<a class="xref" href="clone-plugin-options-variables.html" title="7.6.7.13 Clone System Variables">
Section 7.6.7.13, “Clone System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-distributed-recovery-connections.html#group-replication-recovery-compression" title="20.5.4.1.2 Compression for Distributed Recovery">
Section 20.5.4.1.2, “Compression for Distributed Recovery”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-cloning.html#group-replication-cloning-prerequisites" title="20.5.4.2.1 Prerequisites for Cloning">
Section 20.5.4.2.1, “Prerequisites for Cloning”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
clone_max_concurrency
</h3>
<dl>
<dt>
<a class="xref" href="clone-plugin-options-variables.html" title="7.6.7.13 Clone System Variables">
Section 7.6.7.13, “Clone System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="clone-plugin-monitoring.html" title="7.6.7.10 Monitoring Cloning Operations">
Section 7.6.7.10, “Monitoring Cloning Operations”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
clone_max_data_bandwidth
</h3>
<dl>
<dt>
<a class="xref" href="clone-plugin-options-variables.html" title="7.6.7.13 Clone System Variables">
Section 7.6.7.13, “Clone System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-clone-progress-table.html" title="29.12.19.2 The clone_progress Table">
Section 29.12.19.2, “The clone_progress Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
clone_max_network_bandwidth
</h3>
<dl>
<dt>
<a class="xref" href="clone-plugin-options-variables.html" title="7.6.7.13 Clone System Variables">
Section 7.6.7.13, “Clone System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
clone_ssl_ca
</h3>
<dl>
<dt>
<a class="xref" href="clone-plugin-options-variables.html" title="7.6.7.13 Clone System Variables">
Section 7.6.7.13, “Clone System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="clone-plugin-remote.html" title="7.6.7.3 Cloning Remote Data">
Section 7.6.7.3, “Cloning Remote Data”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-cloning.html#group-replication-cloning-prerequisites" title="20.5.4.2.1 Prerequisites for Cloning">
Section 20.5.4.2.1, “Prerequisites for Cloning”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-configuring-ssl-for-recovery.html" title="20.6.3.2 Secure Socket Layer (SSL) Connections for Distributed Recovery">
Section 20.6.3.2, “Secure Socket Layer (SSL) Connections for Distributed Recovery”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-distributed-recovery-connections.html#group-replication-distributed-recovery-connections-ssl" title="20.5.4.1.4 SSL and Authentication for Distributed Recovery">
Section 20.5.4.1.4, “SSL and Authentication for Distributed Recovery”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
clone_ssl_cert
</h3>
<dl>
<dt>
<a class="xref" href="clone-plugin-options-variables.html" title="7.6.7.13 Clone System Variables">
Section 7.6.7.13, “Clone System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="clone-plugin-remote.html" title="7.6.7.3 Cloning Remote Data">
Section 7.6.7.3, “Cloning Remote Data”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-cloning.html#group-replication-cloning-prerequisites" title="20.5.4.2.1 Prerequisites for Cloning">
Section 20.5.4.2.1, “Prerequisites for Cloning”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-configuring-ssl-for-recovery.html" title="20.6.3.2 Secure Socket Layer (SSL) Connections for Distributed Recovery">
Section 20.6.3.2, “Secure Socket Layer (SSL) Connections for Distributed Recovery”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-distributed-recovery-connections.html#group-replication-distributed-recovery-connections-ssl" title="20.5.4.1.4 SSL and Authentication for Distributed Recovery">
Section 20.5.4.1.4, “SSL and Authentication for Distributed Recovery”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
clone_ssl_key
</h3>
<dl>
<dt>
<a class="xref" href="clone-plugin-options-variables.html" title="7.6.7.13 Clone System Variables">
Section 7.6.7.13, “Clone System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="clone-plugin-remote.html" title="7.6.7.3 Cloning Remote Data">
Section 7.6.7.3, “Cloning Remote Data”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-cloning.html#group-replication-cloning-prerequisites" title="20.5.4.2.1 Prerequisites for Cloning">
Section 20.5.4.2.1, “Prerequisites for Cloning”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-distributed-recovery-connections.html#group-replication-distributed-recovery-connections-ssl" title="20.5.4.1.4 SSL and Authentication for Distributed Recovery">
Section 20.5.4.1.4, “SSL and Authentication for Distributed Recovery”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
clone_valid_donor_list
</h3>
<dl>
<dt>
<a class="xref" href="clone-plugin-options-variables.html" title="7.6.7.13 Clone System Variables">
Section 7.6.7.13, “Clone System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="clone-plugin-remote.html" title="7.6.7.3 Cloning Remote Data">
Section 7.6.7.3, “Cloning Remote Data”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-cloning.html#group-replication-cloning-prerequisites" title="20.5.4.2.1 Prerequisites for Cloning">
Section 20.5.4.2.1, “Prerequisites for Cloning”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
collation_connection
</h3>
<dl>
<dt>
<a class="xref" href="cast-functions.html" title="14.10 Cast Functions and Operators">
Section 14.10, “Cast Functions and Operators”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="string-functions-charset.html" title="14.8.3 Character Set and Collation of Function Results">
Section 14.8.3, “Character Set and Collation of Function Results”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="charset-introducer.html" title="12.3.8 Character Set Introducers">
Section 12.3.8, “Character Set Introducers”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="charset-literal.html" title="12.3.6 Character String Literal Character Set and Collation">
Section 12.3.6, “Character String Literal Character Set and Collation”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="charset-collation-coercibility.html" title="12.8.4 Collation Coercibility in Expressions">
Section 12.8.4, “Collation Coercibility in Expressions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="charset-connection.html" title="12.4 Connection Character Sets and Collations">
Section 12.4, “Connection Character Sets and Collations”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="date-and-time-functions.html" title="14.7 Date and Time Functions">
Section 14.7, “Date and Time Functions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="encryption-functions.html" title="14.13 Encryption and Compression Functions">
Section 14.13, “Encryption and Compression Functions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log-mixed.html" title="7.4.4.3 Mixed Binary Logging Format">
Section 7.4.4.3, “Mixed Binary Logging Format”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="prepare.html" title="15.5.1 PREPARE Statement">
Section 15.5.1, “PREPARE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-variables.html" title="19.5.1.39 Replication and Variables">
Section 19.5.1.39, “Replication and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="set-names.html" title="15.7.6.3 SET NAMES Statement">
Section 15.7.6.3, “SET NAMES Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="show-create-event.html" title="15.7.7.8 SHOW CREATE EVENT Statement">
Section 15.7.7.8, “SHOW CREATE EVENT Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="show-create-procedure.html" title="15.7.7.10 SHOW CREATE PROCEDURE Statement">
Section 15.7.7.10, “SHOW CREATE PROCEDURE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="show-create-trigger.html" title="15.7.7.12 SHOW CREATE TRIGGER Statement">
Section 15.7.7.12, “SHOW CREATE TRIGGER Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="show-create-view.html" title="15.7.7.14 SHOW CREATE VIEW Statement">
Section 15.7.7.14, “SHOW CREATE VIEW Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="show-events.html" title="15.7.7.19 SHOW EVENTS Statement">
Section 15.7.7.19, “SHOW EVENTS Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="show-procedure-status.html" title="15.7.7.30 SHOW PROCEDURE STATUS Statement">
Section 15.7.7.30, “SHOW PROCEDURE STATUS Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="show-triggers.html" title="15.7.7.40 SHOW TRIGGERS Statement">
Section 15.7.7.40, “SHOW TRIGGERS Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log.html" title="7.4.4 The Binary Log">
Section 7.4.4, “The Binary Log”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-events-table.html" title="28.3.14 The INFORMATION_SCHEMA EVENTS Table">
Section 28.3.14, “The INFORMATION_SCHEMA EVENTS Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-routines-table.html" title="28.3.30 The INFORMATION_SCHEMA ROUTINES Table">
Section 28.3.30, “The INFORMATION_SCHEMA ROUTINES Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-triggers-table.html" title="28.3.44 The INFORMATION_SCHEMA TRIGGERS Table">
Section 28.3.44, “The INFORMATION_SCHEMA TRIGGERS Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-views-table.html" title="28.3.47 The INFORMATION_SCHEMA VIEWS Table">
Section 28.3.47, “The INFORMATION_SCHEMA VIEWS Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="type-conversion.html" title="14.3 Type Conversion in Expression Evaluation">
Section 14.3, “Type Conversion in Expression Evaluation”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
collation_database
</h3>
<dl>
<dt>
<a class="xref" href="charset-connection.html" title="12.4 Connection Character Sets and Collations">
Section 12.4, “Connection Character Sets and Collations”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="create-procedure.html" title="15.1.17 CREATE PROCEDURE and CREATE FUNCTION Statements">
Section 15.1.17, “CREATE PROCEDURE and CREATE FUNCTION Statements”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="charset-database.html" title="12.3.3 Database Character Set and Collation">
Section 12.3.3, “Database Character Set and Collation”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log-mixed.html" title="7.4.4.3 Mixed Binary Logging Format">
Section 7.4.4.3, “Mixed Binary Logging Format”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-variables.html" title="19.5.1.39 Replication and Variables">
Section 19.5.1.39, “Replication and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log.html" title="7.4.4 The Binary Log">
Section 7.4.4, “The Binary Log”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
collation_server
</h3>
<dl>
<dt>
<a class="xref" href="charset-connection.html" title="12.4 Connection Character Sets and Collations">
Section 12.4, “Connection Character Sets and Collations”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="charset-database.html" title="12.3.3 Database Character Set and Collation">
Section 12.3.3, “Database Character Set and Collation”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="fulltext-stopwords.html" title="14.9.4 Full-Text Stopwords">
Section 14.9.4, “Full-Text Stopwords”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log-mixed.html" title="7.4.4.3 Mixed Binary Logging Format">
Section 7.4.4.3, “Mixed Binary Logging Format”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-variables.html" title="19.5.1.39 Replication and Variables">
Section 19.5.1.39, “Replication and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="charset-server.html" title="12.3.2 Server Character Set and Collation">
Section 12.3.2, “Server Character Set and Collation”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log.html" title="7.4.4 The Binary Log">
Section 7.4.4, “The Binary Log”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
completion_type
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="commit.html" title="15.3.1 START TRANSACTION, COMMIT, and ROLLBACK Statements">
Section 15.3.1, “START TRANSACTION, COMMIT, and ROLLBACK Statements”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
component_masking
</h3>
<dl>
<dt>
<a class="xref" href="data-masking-components-installation.html" title="8.5.2.1 MySQL Enterprise Data Masking and De-Identification Component Installation">
Section 8.5.2.1, “MySQL Enterprise Data Masking and De-Identification Component Installation”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="data-masking-component-variables.html" title="8.5.2.5 MySQL Enterprise Data Masking and De-Identification Component Variables">
Section 8.5.2.5, “MySQL Enterprise Data Masking and De-Identification Component Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
component_scheduler
</h3>
<dl>
<dt>
<a class="xref" href="audit-log-logging-configuration.html" title="8.4.5.5 Configuring Audit Logging Characteristics">
Section 8.4.5.5, “Configuring Audit Logging Characteristics”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="scheduler-component.html" title="7.5.5 Scheduler Component">
Section 7.5.5, “Scheduler Component”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
concurrent_insert
</h3>
<dl>
<dt>
<a class="xref" href="concurrent-inserts.html" title="10.11.3 Concurrent Inserts">
Section 10.11.3, “Concurrent Inserts”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="internal-locking.html" title="10.11.1 Internal Locking Methods">
Section 10.11.1, “Internal Locking Methods”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="optimizing-queries-myisam.html" title="10.6.1 Optimizing MyISAM Queries">
Section 10.6.1, “Optimizing MyISAM Queries”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-options.html" title="7.1.7 Server Command Options">
Section 7.1.7, “Server Command Options”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
connect_timeout
</h3>
<dl>
<dt>
<a class="xref" href="communication-errors.html" title="B.3.2.9 Communication Errors and Aborted Connections">
Section B.3.2.9, “Communication Errors and Aborted Connections”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="error-lost-connection.html" title="B.3.2.3 Lost connection to MySQL server">
Section B.3.2.3, “Lost connection to MySQL server”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="x-plugin-options-system-variables.html" title="22.5.6.2 X Plugin Options and System Variables">
Section 22.5.6.2, “X Plugin Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
connection_control_failed_connections_threshold
</h3>
<dl>
<dt>
<a class="xref" href="connection-control-installation.html" title="8.4.2.1 Connection-Control Plugin Installation">
Section 8.4.2.1, “Connection-Control Plugin Installation”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="connection-control-variables.html" title="8.4.2.2 Connection-Control System and Status Variables">
Section 8.4.2.2, “Connection-Control System and Status Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-connection-control-failed-login-attempts-table.html" title="28.6.2 The INFORMATION_SCHEMA CONNECTION_CONTROL_FAILED_LOGIN_ATTEMPTS Table">
Section 28.6.2, “The INFORMATION_SCHEMA CONNECTION_CONTROL_FAILED_LOGIN_ATTEMPTS Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
connection_control_max_connection_delay
</h3>
<dl>
<dt>
<a class="xref" href="connection-control-installation.html" title="8.4.2.1 Connection-Control Plugin Installation">
Section 8.4.2.1, “Connection-Control Plugin Installation”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="connection-control-variables.html" title="8.4.2.2 Connection-Control System and Status Variables">
Section 8.4.2.2, “Connection-Control System and Status Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
connection_control_min_connection_delay
</h3>
<dl>
<dt>
<a class="xref" href="connection-control-installation.html" title="8.4.2.1 Connection-Control Plugin Installation">
Section 8.4.2.1, “Connection-Control Plugin Installation”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="connection-control-variables.html" title="8.4.2.2 Connection-Control System and Status Variables">
Section 8.4.2.2, “Connection-Control System and Status Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
connection_memory_chunk_size
</h3>
<dl>
<dt>
<a class="xref" href="server-status-variables.html" title="7.1.10 Server Status Variables">
Section 7.1.10, “Server Status Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
connection_memory_limit
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
core_file
</h3>
<dl>
<dt>
<a class="xref" href="innodb-buffer-pool-in-core-file.html" title="17.8.3.7 Excluding or Including Buffer Pool Pages from Core Files">
Section 17.8.3.7, “Excluding or Including Buffer Pool Pages from Core Files”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
create_admin_listener_thread
</h3>
<dl>
<dt>
<a class="xref" href="administrative-connection-interface.html" title="7.1.12.2 Administrative Connection Management">
Section 7.1.12.2, “Administrative Connection Management”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
cte_max_recursion_depth
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="with.html" title="15.2.20 WITH (Common Table Expressions)">
Section 15.2.20, “WITH (Common Table Expressions)”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<a name="sysvar-index-D">
</a>
<h3 class="title">
D
</h3>
<p>
[
<a class="link" href="dynindex-sysvar.html#sysvar-index-top">
index top
</a>
]
</p>
<dl>
<dt>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
datadir
</h3>
<dl>
<dt>
<a class="xref" href="innodb-create-table-external.html" title="17.6.1.2 Creating Tables Externally">
Section 17.6.1.2, “Creating Tables Externally”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="general-tablespaces.html" title="17.6.3.3 General Tablespaces">
Section 17.6.3.3, “General Tablespaces”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-recovery.html" title="17.18.2 InnoDB Recovery">
Section 17.18.2, “InnoDB Recovery”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-init-startup-configuration.html" title="17.8.1 InnoDB Startup Configuration">
Section 17.8.1, “InnoDB Startup Configuration”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="macos-installation-launchd.html" title="2.4.3 Installing and Using the MySQL Launch Daemon">
Section 2.4.3, “Installing and Using the MySQL Launch Daemon”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="windows-installation.html" title="2.3 Installing MySQL on Microsoft Windows">
Section 2.3, “Installing MySQL on Microsoft Windows”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-moving-data-files-offline.html" title="17.6.3.6 Moving Tablespace Files While the Server is Offline">
Section 17.6.3.6, “Moving Tablespace Files While the Server is Offline”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="glossary.html" title="MySQL Glossary">
MySQL Glossary
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-redo-log.html" title="17.6.5 Redo Log">
Section 17.6.5, “Redo Log”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-options.html" title="7.1.7 Server Command Options">
Section 7.1.7, “Server Command Options”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-files-table.html" title="28.3.15 The INFORMATION_SCHEMA FILES Table">
Section 28.3.15, “The INFORMATION_SCHEMA FILES Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="truncate-table.html" title="15.1.37 TRUNCATE TABLE Statement">
Section 15.1.37, “TRUNCATE TABLE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-undo-tablespaces.html" title="17.6.3.4 Undo Tablespaces">
Section 17.6.3.4, “Undo Tablespaces”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
debug
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="dbug-package.html" title="7.9.4 The DBUG Package">
Section 7.9.4, “The DBUG Package”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
debug_sync
</h3>
<dl>
<dt>
<a class="xref" href="performance-schema-variables-info-table.html" title="29.12.14.2 Performance Schema variables_info Table">
Section 29.12.14.2, “Performance Schema variables_info Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
default
</h3>
<dl>
<dt>
<a class="xref" href="storage-engine-setting.html" title="18.1 Setting the Storage Engine">
Section 18.1, “Setting the Storage Engine”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-benchmarking.html" title="17.1.4 Testing and Benchmarking with InnoDB">
Section 17.1.4, “Testing and Benchmarking with InnoDB”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
default_collation_for_utf
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
default_password_lifetime
</h3>
<dl>
<dt>
<a class="xref" href="alter-user.html" title="15.7.1.1 ALTER USER Statement">
Section 15.7.1.1, “ALTER USER Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="create-user.html" title="15.7.1.3 CREATE USER Statement">
Section 15.7.1.3, “CREATE USER Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="grant-tables.html" title="8.2.3 Grant Tables">
Section 8.2.3, “Grant Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="password-management.html" title="8.2.15 Password Management">
Section 8.2.15, “Password Management”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
default_storage_engine
</h3>
<dl>
<dt>
<a class="xref" href="create-logfile-group.html" title="15.1.16 CREATE LOGFILE GROUP Statement">
Section 15.1.16, “CREATE LOGFILE GROUP Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="create-table.html" title="15.1.20 CREATE TABLE Statement">
Section 15.1.20, “CREATE TABLE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="create-tablespace.html" title="15.1.21 CREATE TABLESPACE Statement">
Section 15.1.21, “CREATE TABLESPACE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="general-tablespaces.html" title="17.6.3.3 General Tablespaces">
Section 17.6.3.3, “General Tablespaces”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="partitioning-list.html" title="26.2.2 LIST Partitioning">
Section 26.2.2, “LIST Partitioning”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="partitioning-overview.html" title="26.1 Overview of Partitioning in MySQL">
Section 26.1, “Overview of Partitioning in MySQL”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-variables.html" title="19.5.1.39 Replication and Variables">
Section 19.5.1.39, “Replication and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="storage-engine-setting.html" title="18.1 Setting the Storage Engine">
Section 18.1, “Setting the Storage Engine”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-solutions-diffengines.html" title="19.4.4 Using Replication with Different Source and Replica Storage Engines">
Section 19.4.4, “Using Replication with Different Source and Replica Storage Engines”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
default_table_encryption
</h3>
<dl>
<dt>
<a class="xref" href="alter-database.html" title="15.1.2 ALTER DATABASE Statement">
Section 15.1.2, “ALTER DATABASE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="alter-tablespace.html" title="15.1.10 ALTER TABLESPACE Statement">
Section 15.1.10, “ALTER TABLESPACE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="create-database.html" title="15.1.12 CREATE DATABASE Statement">
Section 15.1.12, “CREATE DATABASE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="create-tablespace.html" title="15.1.21 CREATE TABLESPACE Statement">
Section 15.1.21, “CREATE TABLESPACE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-requirements.html" title="20.3.1 Group Replication Requirements">
Section 20.3.1, “Group Replication Requirements”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-data-encryption.html" title="17.13 InnoDB Data-at-Rest Encryption">
Section 17.13, “InnoDB Data-at-Rest Encryption”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-privilege-checks-account.html" title="19.3.3.1 Privileges For The Replication PRIVILEGE_CHECKS_USER Account">
Section 19.3.3.1, “Privileges For The Replication PRIVILEGE_CHECKS_USER Account”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="system-variable-privileges.html" title="7.1.9.1 System Variable Privileges">
Section 7.1.9.1, “System Variable Privileges”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
default_tmp_storage_engine
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="storage-engine-setting.html" title="18.1 Setting the Storage Engine">
Section 18.1, “Setting the Storage Engine”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
default_week_format
</h3>
<dl>
<dt>
<a class="xref" href="date-and-time-functions.html" title="14.7 Date and Time Functions">
Section 14.7, “Date and Time Functions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="partitioning-limitations-functions.html" title="26.6.3 Partitioning Limitations Relating to Functions">
Section 26.6.3, “Partitioning Limitations Relating to Functions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
delay_key_write
</h3>
<dl>
<dt>
<a class="xref" href="create-table.html" title="15.1.20 CREATE TABLE Statement">
Section 15.1.20, “CREATE TABLE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="external-locking.html" title="10.11.5 External Locking">
Section 10.11.5, “External Locking”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="faqs-replication.html" title="A.14 MySQL 8.4 FAQ: Replication">
Section A.14, “MySQL 8.4 FAQ: Replication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-options.html" title="7.1.7 Server Command Options">
Section 7.1.7, “Server Command Options”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="crashing.html" title="B.3.3.3 What to Do If MySQL Keeps Crashing">
Section B.3.3.3, “What to Do If MySQL Keeps Crashing”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
delayed_insert_limit
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
delayed_insert_timeout
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
delayed_queue_size
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
disabled_storage_engines
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-configuring-instances.html" title="20.2.1.2 Configuring an Instance for Group Replication">
Section 20.2.1.2, “Configuring an Instance for Group Replication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-requirements.html" title="20.3.1 Group Replication Requirements">
Section 20.3.1, “Group Replication Requirements”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="faqs-storage-engines.html" title="A.2 MySQL 8.4 FAQ: Storage Engines">
Section A.2, “MySQL 8.4 FAQ: Storage Engines”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-options.html" title="7.1.7 Server Command Options">
Section 7.1.7, “Server Command Options”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
disconnect_on_expired_password
</h3>
<dl>
<dt>
<a class="xref" href="expired-password-handling.html" title="8.2.16 Server Handling of Expired Passwords">
Section 8.2.16, “Server Handling of Expired Passwords”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
div_precision_increment
</h3>
<dl>
<dt>
<a class="xref" href="arithmetic-functions.html" title="14.6.1 Arithmetic Operators">
Section 14.6.1, “Arithmetic Operators”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
dragnet
</h3>
<dl>
<dt>
<a class="xref" href="error-log-components.html" title="7.5.3 Error Log Components">
Section 7.5.3, “Error Log Components”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="components.html" title="7.5 MySQL Components">
Section 7.5, “MySQL Components”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="error-log-rule-based-filtering.html" title="7.4.2.6 Rule-Based Error Log Filtering (log_filter_dragnet)">
Section 7.4.2.6, “Rule-Based Error Log Filtering (log_filter_dragnet)”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-status-variables.html" title="7.1.10 Server Status Variables">
Section 7.1.10, “Server Status Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="error-log-filtering.html" title="7.4.2.4 Types of Error Log Filtering">
Section 7.4.2.4, “Types of Error Log Filtering”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="using-system-variables.html" title="7.1.9 Using System Variables">
Section 7.1.9, “Using System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<a name="sysvar-index-E">
</a>
<h3 class="title">
E
</h3>
<p>
[
<a class="link" href="dynindex-sysvar.html#sysvar-index-top">
index top
</a>
]
</p>
<dl>
<dt>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
end_markers_in_json
</h3>
<dl>
<dt>
<a class="xref" href="displaying-traces.html" title="10.15.13 Displaying Traces in Other Applications">
Section 10.15.13, “Displaying Traces in Other Applications”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="explain.html" title="15.8.2 EXPLAIN Statement">
Section 15.8.2, “EXPLAIN Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="system-variables-controlling-tracing.html" title="10.15.2 System Variables Controlling Tracing">
Section 10.15.2, “System Variables Controlling Tracing”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
enforce_gtid_consistency
</h3>
<dl>
<dt>
<a class="xref" href="replication-mode-change-online-disable-gtids.html" title="19.1.4.3 Disabling GTID Transactions Online">
Section 19.1.4.3, “Disabling GTID Transactions Online”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-gtids.html" title="19.1.6.5 Global Transaction ID System Variables">
Section 19.1.6.5, “Global Transaction ID System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-requirements.html" title="20.3.1 Group Replication Requirements">
Section 20.3.1, “Group Replication Requirements”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-gtids.html" title="20.4.1 GTIDs and Group Replication">
Section 20.4.1, “GTIDs and Group Replication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-temptables.html" title="19.5.1.31 Replication and Temporary Tables">
Section 19.5.1.31, “Replication and Temporary Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-mode-change-online-concepts.html" title="19.1.4.1 Replication Mode Concepts">
Section 19.1.4.1, “Replication Mode Concepts”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-gtids-restrictions.html" title="19.1.3.7 Restrictions on Replication with GTIDs">
Section 19.1.3.7, “Restrictions on Replication with GTIDs”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-gtids-howto.html" title="19.1.3.4 Setting Up Replication Using GTIDs">
Section 19.1.3.4, “Setting Up Replication Using GTIDs”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
enterprise_encryption
</h3>
<dl>
<dt>
<a class="xref" href="enterprise-encryption-configuring.html" title="8.6.2 Configuring MySQL Enterprise Encryption">
Section 8.6.2, “Configuring MySQL Enterprise Encryption”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="enterprise-encryption-functions.html" title="8.6.5 MySQL Enterprise Encryption Component Function Descriptions">
Section 8.6.5, “MySQL Enterprise Encryption Component Function Descriptions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="enterprise-encryption-installation.html" title="8.6.1 MySQL Enterprise Encryption Installation and Upgrading">
Section 8.6.1, “MySQL Enterprise Encryption Installation and Upgrading”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
eq_range_index_dive_limit
</h3>
<dl>
<dt>
<a class="xref" href="range-optimization.html" title="10.2.1.2 Range Optimization">
Section 10.2.1.2, “Range Optimization”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
error_count
</h3>
<dl>
<dt>
<a class="xref" href="error-interfaces.html" title="B.2 Error Information Interfaces">
Section B.2, “Error Information Interfaces”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="sql-prepared-statements.html" title="15.5 Prepared Statements">
Section 15.5, “Prepared Statements”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="show-errors.html" title="15.7.7.18 SHOW ERRORS Statement">
Section 15.7.7.18, “SHOW ERRORS Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="diagnostics-area.html" title="15.6.7.7 The MySQL Diagnostics Area">
Section 15.6.7.7, “The MySQL Diagnostics Area”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
event
</h3>
<dl>
<dt>
<a class="xref" href="innodb-read-only-instance.html" title="17.8.2 Configuring InnoDB for Read-Only Operation">
Section 17.8.2, “Configuring InnoDB for Read-Only Operation”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
event_scheduler
</h3>
<dl>
<dt>
<a class="xref" href="replication-howto-additionalslaves.html" title="19.1.2.8 Adding Replicas to a Replication Environment">
Section 19.1.2.8, “Adding Replicas to a Replication Environment”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="events-configuration.html" title="27.4.2 Event Scheduler Configuration">
Section 27.4.2, “Event Scheduler Configuration”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-setup-replicas.html#replication-howto-existingdata" title="19.1.2.6.2 Setting Up Replication with Existing Data">
Section 19.1.2.6.2, “Setting Up Replication with Existing Data”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="events-privileges.html" title="27.4.6 The Event Scheduler and MySQL Privileges">
Section 27.4.6, “The Event Scheduler and MySQL Privileges”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
explain_format
</h3>
<dl>
<dt>
<a class="xref" href="explain.html" title="15.8.2 EXPLAIN Statement">
Section 15.8.2, “EXPLAIN Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
explain_json_format_version
</h3>
<dl>
<dt>
<a class="xref" href="explain.html" title="15.8.2 EXPLAIN Statement">
Section 15.8.2, “EXPLAIN Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
explicit_defaults_for_timestamp
</h3>
<dl>
<dt>
<a class="xref" href="timestamp-initialization.html" title="13.2.5 Automatic Initialization and Updating for TIMESTAMP and DATETIME">
Section 13.2.5, “Automatic Initialization and Updating for TIMESTAMP and DATETIME”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="create-table-generated-columns.html" title="15.1.20.8 CREATE TABLE and Generated Columns">
Section 15.1.20.8, “CREATE TABLE and Generated Columns”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="data-type-defaults.html" title="13.6 Data Type Default Values">
Section 13.6, “Data Type Default Values”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="date-and-time-type-syntax.html" title="13.2.1 Date and Time Data Type Syntax">
Section 13.2.1, “Date and Time Data Type Syntax”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="problems-with-null.html" title="B.3.4.3 Problems with NULL Values">
Section B.3.4.3, “Problems with NULL Values”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
external_user
</h3>
<dl>
<dt>
<a class="xref" href="audit-log-file-formats.html" title="8.4.5.4 Audit Log File Formats">
Section 8.4.5.4, “Audit Log File Formats”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="proxy-users.html" title="8.2.19 Proxy Users">
Section 8.2.19, “Proxy Users”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<a name="sysvar-index-F">
</a>
<h3 class="title">
F
</h3>
<p>
[
<a class="link" href="dynindex-sysvar.html#sysvar-index-top">
index top
</a>
]
</p>
<dl>
<dt>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
flush
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
flush_time
</h3>
<dl>
<dt>
<a class="xref" href="server-options.html" title="7.1.7 Server Command Options">
Section 7.1.7, “Server Command Options”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
foreign_key_checks
</h3>
<dl>
<dt>
<a class="xref" href="alter-table.html" title="15.1.9 ALTER TABLE Statement">
Section 15.1.9, “ALTER TABLE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="create-table-foreign-keys.html" title="15.1.20.5 FOREIGN KEY Constraints">
Section 15.1.20.5, “FOREIGN KEY Constraints”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-importing-data.html" title="25.6.9 Importing Data Into MySQL Cluster">
Section 25.6.9, “Importing Data Into MySQL Cluster”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-table-import.html" title="17.6.1.3 Importing InnoDB Tables">
Section 17.6.1.3, “Importing InnoDB Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log-mixed.html" title="7.4.4.3 Mixed Binary Logging Format">
Section 7.4.4.3, “Mixed Binary Logging Format”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-online-ddl-operations.html" title="17.12.1 Online DDL Operations">
Section 17.12.1, “Online DDL Operations”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-variables.html" title="19.5.1.39 Replication and Variables">
Section 19.5.1.39, “Replication and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="sql-mode.html" title="7.1.11 Server SQL Modes">
Section 7.1.11, “Server SQL Modes”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log.html" title="7.4.4 The Binary Log">
Section 7.4.4, “The Binary Log”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ft_boolean_syntax
</h3>
<dl>
<dt>
<a class="xref" href="fulltext-boolean.html" title="14.9.2 Boolean Full-Text Searches">
Section 14.9.2, “Boolean Full-Text Searches”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="fulltext-fine-tuning.html" title="14.9.6 Fine-Tuning MySQL Full-Text Search">
Section 14.9.6, “Fine-Tuning MySQL Full-Text Search”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ft_max_word_len
</h3>
<dl>
<dt>
<a class="xref" href="fulltext-boolean.html" title="14.9.2 Boolean Full-Text Searches">
Section 14.9.2, “Boolean Full-Text Searches”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-snapshot-method.html#replication-howto-rawdata" title="19.1.2.5.2 Creating a Data Snapshot Using Raw Data Files">
Section 19.1.2.5.2, “Creating a Data Snapshot Using Raw Data Files”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="fulltext-fine-tuning.html" title="14.9.6 Fine-Tuning MySQL Full-Text Search">
Section 14.9.6, “Fine-Tuning MySQL Full-Text Search”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="fulltext-search-ngram.html" title="14.9.8 ngram Full-Text Parser">
Section 14.9.8, “ngram Full-Text Parser”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ft_min_word_len
</h3>
<dl>
<dt>
<a class="xref" href="fulltext-boolean.html" title="14.9.2 Boolean Full-Text Searches">
Section 14.9.2, “Boolean Full-Text Searches”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-snapshot-method.html#replication-howto-rawdata" title="19.1.2.5.2 Creating a Data Snapshot Using Raw Data Files">
Section 19.1.2.5.2, “Creating a Data Snapshot Using Raw Data Files”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="fulltext-fine-tuning.html" title="14.9.6 Fine-Tuning MySQL Full-Text Search">
Section 14.9.6, “Fine-Tuning MySQL Full-Text Search”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="fulltext-search-mecab.html" title="14.9.9 MeCab Full-Text Parser Plugin">
Section 14.9.9, “MeCab Full-Text Parser Plugin”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="fulltext-natural-language.html" title="14.9.1 Natural Language Full-Text Searches">
Section 14.9.1, “Natural Language Full-Text Searches”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="fulltext-search-ngram.html" title="14.9.8 ngram Full-Text Parser">
Section 14.9.8, “ngram Full-Text Parser”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ft_query_expansion_limit
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ft_stopword_file
</h3>
<dl>
<dt>
<a class="xref" href="fulltext-boolean.html" title="14.9.2 Boolean Full-Text Searches">
Section 14.9.2, “Boolean Full-Text Searches”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-snapshot-method.html#replication-howto-rawdata" title="19.1.2.5.2 Creating a Data Snapshot Using Raw Data Files">
Section 19.1.2.5.2, “Creating a Data Snapshot Using Raw Data Files”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="fulltext-fine-tuning.html" title="14.9.6 Fine-Tuning MySQL Full-Text Search">
Section 14.9.6, “Fine-Tuning MySQL Full-Text Search”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="fulltext-stopwords.html" title="14.9.4 Full-Text Stopwords">
Section 14.9.4, “Full-Text Stopwords”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="fulltext-natural-language.html" title="14.9.1 Natural Language Full-Text Searches">
Section 14.9.1, “Natural Language Full-Text Searches”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<a name="sysvar-index-G">
</a>
<h3 class="title">
G
</h3>
<p>
[
<a class="link" href="dynindex-sysvar.html#sysvar-index-top">
index top
</a>
]
</p>
<dl>
<dt>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
general_log
</h3>
<dl>
<dt>
<a class="xref" href="glossary.html" title="MySQL Glossary">
MySQL Glossary
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="log-destinations.html" title="7.4.1 Selecting General Query Log and Slow Query Log Output Destinations">
Section 7.4.1, “Selecting General Query Log and Slow Query Log Output Destinations”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="query-log.html" title="7.4.3 The General Query Log">
Section 7.4.3, “The General Query Log”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
general_log_file
</h3>
<dl>
<dt>
<a class="xref" href="log-destinations.html" title="7.4.1 Selecting General Query Log and Slow Query Log Output Destinations">
Section 7.4.1, “Selecting General Query Log and Slow Query Log Output Destinations”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="query-log.html" title="7.4.3 The General Query Log">
Section 7.4.3, “The General Query Log”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
generated_random_password_length
</h3>
<dl>
<dt>
<a class="xref" href="password-management.html" title="8.2.15 Password Management">
Section 8.2.15, “Password Management”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
global_connection_memory_limit
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
global_connection_memory_tracking
</h3>
<dl>
<dt>
<a class="xref" href="server-status-variables.html" title="7.1.10 Server Status Variables">
Section 7.1.10, “Server Status Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_concat_max_len
</h3>
<dl>
<dt>
<a class="xref" href="aggregate-functions.html" title="14.19.1 Aggregate Function Descriptions">
Section 14.19.1, “Aggregate Function Descriptions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_advertise_recovery_endpoints
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-distributed-recovery-connections.html" title="20.5.4.1 Connections for Distributed Recovery">
Section 20.5.4.1, “Connections for Distributed Recovery”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-distributed-recovery-connections.html#group-replication-distributed-recovery-connections-endpoints" title="20.5.4.1.1 Selecting addresses for distributed recovery endpoints">
Section 20.5.4.1.1, “Selecting addresses for distributed recovery endpoints”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-ipv6.html" title="20.5.5 Support For IPv6 And For Mixed IPv6 And IPv4 Groups">
Section 20.5.5, “Support For IPv6 And For Mixed IPv6 And IPv4 Groups”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_allow_local_lower_version_join
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-compatibility-upgrade.html" title="20.8.1.1 Member Versions During Upgrades">
Section 20.8.1.1, “Member Versions During Upgrades”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_auto_increment_increment
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-frequently-asked-questions.html" title="20.10 Frequently Asked Questions">
Section 20.10, “Frequently Asked Questions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-source.html" title="19.1.6.2 Replication Source Options and Variables">
Section 19.1.6.2, “Replication Source Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_autorejoin_tries
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-responses-failure-rejoin.html" title="20.7.7.3 Auto-Rejoin">
Section 20.7.7.3, “Auto-Rejoin”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-responses-failure-exit.html" title="20.7.7.4 Exit Action">
Section 20.7.7.4, “Exit Action”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-responses-failure-expel.html" title="20.7.7.1 Expel Timeout">
Section 20.7.7.1, “Expel Timeout”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-frequently-asked-questions.html" title="20.10 Frequently Asked Questions">
Section 20.10, “Frequently Asked Questions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-responses-failure-partition.html" title="20.7.7.2 Unreachable Majority Timeout">
Section 20.7.7.2, “Unreachable Majority Timeout”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_bootstrap_group
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-adding-instances.html#group-replication-adding-a-second-instance" title="20.2.1.6.1 Adding a Second Instance">
Section 20.2.1.6.1, “Adding a Second Instance”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-bootstrap.html" title="20.2.1.5 Bootstrapping the Group">
Section 20.2.1.5, “Bootstrapping the Group”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-connection-security.html" title="20.6.1 Communication Stack for Connection Security Management">
Section 20.6.1, “Communication Stack for Connection Security Management”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-configuring-instances.html" title="20.2.1.2 Configuring an Instance for Group Replication">
Section 20.2.1.2, “Configuring an Instance for Group Replication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-deploying-in-multi-primary-or-single-primary-mode.html" title="20.1.3 Multi-Primary and Single-Primary Modes">
Section 20.1.3, “Multi-Primary and Single-Primary Modes”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-restarting-group.html" title="20.5.2 Restarting a Group">
Section 20.5.2, “Restarting a Group”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_clone_threshold
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-cloning.html" title="20.5.4.2 Cloning for Distributed Recovery">
Section 20.5.4.2, “Cloning for Distributed Recovery”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-view-changes.html" title="20.5.4.5 How Distributed Recovery Works">
Section 20.5.4.5, “How Distributed Recovery Works”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-cloning.html#group-replication-cloning-threshold" title="20.5.4.2.2 Threshold for Cloning">
Section 20.5.4.2.2, “Threshold for Cloning”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_communication_debug_options
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_communication_max_message_size
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-limitations.html" title="20.3.2 Group Replication Limitations">
Section 20.3.2, “Group Replication Limitations”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-performance-message-fragmentation.html" title="20.7.5 Message Fragmentation">
Section 20.7.5, “Message Fragmentation”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_communication_stack
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-connection-security.html" title="20.6.1 Communication Stack for Connection Security Management">
Section 20.6.1, “Communication Stack for Connection Security Management”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-ip-address-permissions.html" title="20.6.4 Group Replication IP Address Permissions">
Section 20.6.4, “Group Replication IP Address Permissions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="privileges-provided.html" title="8.2.2 Privileges Provided by MySQL">
Section 8.2.2, “Privileges Provided by MySQL”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-secure-user.html#group-replication-secure-user-ssl" title="20.6.3.1.2 Replication User With SSL">
Section 20.6.3.1.2, “Replication User With SSL”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-configuring-ssl-for-recovery.html" title="20.6.3.2 Secure Socket Layer (SSL) Connections for Distributed Recovery">
Section 20.6.3.2, “Secure Socket Layer (SSL) Connections for Distributed Recovery”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-secure-user.html" title="20.6.3.1 Secure User Credentials for Distributed Recovery">
Section 20.6.3.1, “Secure User Credentials for Distributed Recovery”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-distributed-recovery-securing.html" title="20.6.3 Securing Distributed Recovery Connections">
Section 20.6.3, “Securing Distributed Recovery Connections”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-secure-socket-layer-support-ssl.html" title="20.6.2 Securing Group Communication Connections with Secure Socket Layer (SSL)">
Section 20.6.2, “Securing Group Communication Connections with Secure Socket Layer (SSL)”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_components_stop_timeout
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="stop-group-replication.html" title="15.4.3.2 STOP GROUP_REPLICATION Statement">
Section 15.4.3.2, “STOP GROUP_REPLICATION Statement”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_compression_threshold
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-limitations.html" title="20.3.2 Group Replication Limitations">
Section 20.3.2, “Group Replication Limitations”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-message-compression.html" title="20.7.4 Message Compression">
Section 20.7.4, “Message Compression”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log-transaction-compression.html#binary-log-transaction-compression-monitoring" title="7.4.4.5.3 Monitoring Binary Log Transaction Compression">
Section 7.4.4.5.3, “Monitoring Binary Log Transaction Compression”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_consistency
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-configuring-consistency-guarantees.html" title="20.5.3.2 Configuring Transaction Consistency Guarantees">
Section 20.5.3.2, “Configuring Transaction Consistency Guarantees”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-status-variables.html" title="20.9.2 Group Replication Status Variables">
Section 20.9.2, “Group Replication Status Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-multi-primary-mode.html" title="20.1.3.2 Multi-Primary Mode">
Section 20.1.3.2, “Multi-Primary Mode”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="privileges-provided.html" title="8.2.2 Privileges Provided by MySQL">
Section 8.2.2, “Privileges Provided by MySQL”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-single-primary-mode.html" title="20.1.3.1 Single-Primary Mode">
Section 20.1.3.1, “Single-Primary Mode”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-understanding-consistency-guarantees.html" title="20.5.3.1 Understanding Transaction Consistency Guarantees">
Section 20.5.3.1, “Understanding Transaction Consistency Guarantees”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_enforce_update_everywhere_checks
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-changing-group-mode.html" title="20.5.1.2 Changing the Group Mode">
Section 20.5.1.2, “Changing the Group Mode”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-functions-for-mode.html" title="14.18.1.2 Functions which Configure the Group Replication Mode">
Section 14.18.1.2, “Functions which Configure the Group Replication Mode”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-limitations.html" title="20.3.2 Group Replication Limitations">
Section 20.3.2, “Group Replication Limitations”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-single-primary-mode.html" title="20.1.3.1 Single-Primary Mode">
Section 20.1.3.1, “Single-Primary Mode”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-multi-primary-mode.html#group-replication-multi-primary-checks" title="20.1.3.2.1 Transaction Checks">
Section 20.1.3.2.1, “Transaction Checks”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_exit_state_action
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-responses-failure-rejoin.html" title="20.7.7.3 Auto-Rejoin">
Section 20.7.7.3, “Auto-Rejoin”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-member-actions.html" title="20.5.1.5 Configuring Member Actions">
Section 20.5.1.5, “Configuring Member Actions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-responses-failure-exit.html" title="20.7.7.4 Exit Action">
Section 20.7.7.4, “Exit Action”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-responses-failure-expel.html" title="20.7.7.1 Expel Timeout">
Section 20.7.7.1, “Expel Timeout”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-distributed-recovery-fault.html" title="20.5.4.4 Fault Tolerance for Distributed Recovery">
Section 20.5.4.4, “Fault Tolerance for Distributed Recovery”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-server-states.html" title="20.4.2 Group Replication Server States">
Section 20.4.2, “Group Replication Server States”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-replication-group-member-actions-table.html" title="29.12.11.14 The replication_group_member_actions Table">
Section 29.12.11.14, “The replication_group_member_actions Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-responses-failure-partition.html" title="20.7.7.2 Unreachable Majority Timeout">
Section 20.7.7.2, “Unreachable Majority Timeout”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_flow_control_applier_threshold
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_flow_control_certifier_threshold
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_flow_control_hold_percent
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_flow_control_max_quota
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_flow_control_member_quota_percent
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_flow_control_min_quota
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_flow_control_min_recovery_quota
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_flow_control_mode
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_flow_control_period
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-replication-group-member-stats.html" title="20.4.4 The replication_group_member_stats Table">
Section 20.4.4, “The replication_group_member_stats Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_flow_control_release_percent
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_force_members
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-network-partitioning.html" title="20.7.8 Handling a Network Partition and Loss of Quorum">
Section 20.7.8, “Handling a Network Partition and Loss of Quorum”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_group_name
</h3>
<dl>
<dt>
<a class="xref" href="replication-asynchronous-connection-failover-source.html" title="19.4.9.1 Asynchronous Connection Failover for Sources">
Section 19.4.9.1, “Asynchronous Connection Failover for Sources”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-functions-async-failover.html" title="14.18.3 Asynchronous Replication Channel Failover Functions">
Section 14.18.3, “Asynchronous Replication Channel Failover Functions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-configuring-instances.html" title="20.2.1.2 Configuring an Instance for Group Replication">
Section 20.2.1.2, “Configuring an Instance for Group Replication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-gtids.html" title="20.4.1 GTIDs and Group Replication">
Section 20.4.1, “GTIDs and Group Replication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-replication-asynchronous-connection-failover-table.html" title="29.12.11.8 The replication_asynchronous_connection_failover Table">
Section 29.12.11.8, “The replication_asynchronous_connection_failover Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-replication-asynchronous-connection-failover-managed-table.html" title="29.12.11.9 The replication_asynchronous_connection_failover_managed Table">
Section 29.12.11.9, “The replication_asynchronous_connection_failover_managed Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_group_seeds
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-connection-security.html" title="20.6.1 Communication Stack for Connection Security Management">
Section 20.6.1, “Communication Stack for Connection Security Management”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-configuring-instances.html" title="20.2.1.2 Configuring an Instance for Group Replication">
Section 20.2.1.2, “Configuring an Instance for Group Replication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-distributed-recovery-connections.html" title="20.5.4.1 Connections for Distributed Recovery">
Section 20.5.4.1, “Connections for Distributed Recovery”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-deploying-locally.html" title="20.2.2 Deploying Group Replication Locally">
Section 20.2.2, “Deploying Group Replication Locally”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-ip-address-permissions.html" title="20.6.4 Group Replication IP Address Permissions">
Section 20.6.4, “Group Replication IP Address Permissions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-ipv6.html" title="20.5.5 Support For IPv6 And For Mixed IPv6 And IPv4 Groups">
Section 20.5.5, “Support For IPv6 And For Mixed IPv6 And IPv4 Groups”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_gtid_assignment_block_size
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-gtids.html" title="20.4.1 GTIDs and Group Replication">
Section 20.4.1, “GTIDs and Group Replication”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_ip_allowlist
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-connection-security.html" title="20.6.1 Communication Stack for Connection Security Management">
Section 20.6.1, “Communication Stack for Connection Security Management”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-ip-address-permissions.html" title="20.6.4 Group Replication IP Address Permissions">
Section 20.6.4, “Group Replication IP Address Permissions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-distributed-recovery-connections.html#group-replication-distributed-recovery-connections-endpoints" title="20.5.4.1.1 Selecting addresses for distributed recovery endpoints">
Section 20.5.4.1.1, “Selecting addresses for distributed recovery endpoints”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-ipv6.html" title="20.5.5 Support For IPv6 And For Mixed IPv6 And IPv4 Groups">
Section 20.5.5, “Support For IPv6 And For Mixed IPv6 And IPv4 Groups”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_local_address
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-connection-security.html" title="20.6.1 Communication Stack for Connection Security Management">
Section 20.6.1, “Communication Stack for Connection Security Management”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-configuring-instances.html" title="20.2.1.2 Configuring an Instance for Group Replication">
Section 20.2.1.2, “Configuring an Instance for Group Replication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-distributed-recovery-connections.html" title="20.5.4.1 Connections for Distributed Recovery">
Section 20.5.4.1, “Connections for Distributed Recovery”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-deploying-locally.html" title="20.2.2 Deploying Group Replication Locally">
Section 20.2.2, “Deploying Group Replication Locally”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-frequently-asked-questions.html" title="20.10 Frequently Asked Questions">
Section 20.10, “Frequently Asked Questions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-ip-address-permissions.html" title="20.6.4 Group Replication IP Address Permissions">
Section 20.6.4, “Group Replication IP Address Permissions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-distributed-recovery-connections.html#group-replication-distributed-recovery-connections-endpoints" title="20.5.4.1.1 Selecting addresses for distributed recovery endpoints">
Section 20.5.4.1.1, “Selecting addresses for distributed recovery endpoints”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="selinux-context-mysql-feature-ports.html" title="8.7.5.2 Setting the TCP Port Context for MySQL Features">
Section 8.7.5.2, “Setting the TCP Port Context for MySQL Features”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-ipv6.html" title="20.5.5 Support For IPv6 And For Mixed IPv6 And IPv4 Groups">
Section 20.5.5, “Support For IPv6 And For Mixed IPv6 And IPv4 Groups”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-replication-group-members-table.html" title="29.12.11.16 The replication_group_members Table">
Section 29.12.11.16, “The replication_group_members Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_member_expel_timeout
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-responses-failure-exit.html" title="20.7.7.4 Exit Action">
Section 20.7.7.4, “Exit Action”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-responses-failure-expel.html" title="20.7.7.1 Expel Timeout">
Section 20.7.7.1, “Expel Timeout”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-failure-detection.html" title="20.1.4.2 Failure Detection">
Section 20.1.4.2, “Failure Detection”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-frequently-asked-questions.html" title="20.10 Frequently Asked Questions">
Section 20.10, “Frequently Asked Questions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-group-membership.html" title="20.1.4.1 Group Membership">
Section 20.1.4.1, “Group Membership”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-limitations.html" title="20.3.2 Group Replication Limitations">
Section 20.3.2, “Group Replication Limitations”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-performance-xcom-cache-increase.html" title="20.7.6.1 Increasing the cache size">
Section 20.7.6.1, “Increasing the cache size”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-performance-message-fragmentation.html" title="20.7.5 Message Fragmentation">
Section 20.7.5, “Message Fragmentation”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-responses-failure.html" title="20.7.7 Responses to Failure Detection and Network Partitioning">
Section 20.7.7, “Responses to Failure Detection and Network Partitioning”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-performance-xcom-cache.html" title="20.7.6 XCom Cache Management">
Section 20.7.6, “XCom Cache Management”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_member_weight
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-single-primary-mode.html#group-replication-primary-election" title="20.1.3.1.1 Primary Election Algorithm">
Section 20.1.3.1.1, “Primary Election Algorithm”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_message_cache_size
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-responses-failure-expel.html" title="20.7.7.1 Expel Timeout">
Section 20.7.7.1, “Expel Timeout”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-performance-xcom-cache-increase.html" title="20.7.6.1 Increasing the cache size">
Section 20.7.6.1, “Increasing the cache size”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-performance-xcom-cache-reduce.html" title="20.7.6.2 Reducing the cache size">
Section 20.7.6.2, “Reducing the cache size”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-performance-xcom-cache.html" title="20.7.6 XCom Cache Management">
Section 20.7.6, “XCom Cache Management”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_paxos_single_leader
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-communication-protocol.html" title="20.5.1.4 Setting a Group's Communication Protocol Version">
Section 20.5.1.4, “Setting a Group's Communication Protocol Version”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-single-consensus-leader.html" title="20.7.3 Single Consensus Leader">
Section 20.7.3, “Single Consensus Leader”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-replication-group-communication-information-table.html" title="29.12.11.10 The replication_group_communication_information Table">
Section 29.12.11.10, “The replication_group_communication_information Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_poll_spin_loops
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-fine-tuning-the-group-communication-thread.html" title="20.7.1 Fine Tuning the Group Communication Thread">
Section 20.7.1, “Fine Tuning the Group Communication Thread”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_preemptive_garbage_collection
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_preemptive_garbage_collection_rows_threshold
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_recovery_compression_algorithms
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-distributed-recovery-connections.html#group-replication-recovery-compression" title="20.5.4.1.2 Compression for Distributed Recovery">
Section 20.5.4.1.2, “Compression for Distributed Recovery”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="connection-compression-control.html" title="6.2.8 Connection Compression Control">
Section 6.2.8, “Connection Compression Control”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-message-compression.html" title="20.7.4 Message Compression">
Section 20.7.4, “Message Compression”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log-transaction-compression.html#binary-log-transaction-compression-monitoring" title="7.4.4.5.3 Monitoring Binary Log Transaction Compression">
Section 7.4.4.5.3, “Monitoring Binary Log Transaction Compression”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_recovery_get_public_key
</h3>
<dl>
<dt>
<a class="xref" href="caching-sha2-pluggable-authentication.html" title="8.4.1.2 Caching SHA-2 Pluggable Authentication">
Section 8.4.1.2, “Caching SHA-2 Pluggable Authentication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-secure-user.html#group-replication-caching-sha2-user-credentials" title="20.6.3.1.1 Replication User With The Caching SHA-2 Authentication Plugin">
Section 20.6.3.1.1, “Replication User With The Caching SHA-2 Authentication Plugin”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="sha256-pluggable-authentication.html" title="8.4.1.3 SHA-256 Pluggable Authentication">
Section 8.4.1.3, “SHA-256 Pluggable Authentication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-distributed-recovery-connections.html#group-replication-distributed-recovery-connections-ssl" title="20.5.4.1.4 SSL and Authentication for Distributed Recovery">
Section 20.5.4.1.4, “SSL and Authentication for Distributed Recovery”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_recovery_public_key_path
</h3>
<dl>
<dt>
<a class="xref" href="caching-sha2-pluggable-authentication.html" title="8.4.1.2 Caching SHA-2 Pluggable Authentication">
Section 8.4.1.2, “Caching SHA-2 Pluggable Authentication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-secure-user.html#group-replication-caching-sha2-user-credentials" title="20.6.3.1.1 Replication User With The Caching SHA-2 Authentication Plugin">
Section 20.6.3.1.1, “Replication User With The Caching SHA-2 Authentication Plugin”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-distributed-recovery-connections.html#group-replication-distributed-recovery-connections-ssl" title="20.5.4.1.4 SSL and Authentication for Distributed Recovery">
Section 20.5.4.1.4, “SSL and Authentication for Distributed Recovery”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_recovery_reconnect_interval
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-tuning-recovery.html" title="20.5.4.3 Configuring Distributed Recovery">
Section 20.5.4.3, “Configuring Distributed Recovery”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_recovery_retry_count
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-tuning-recovery.html" title="20.5.4.3 Configuring Distributed Recovery">
Section 20.5.4.3, “Configuring Distributed Recovery”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-distributed-recovery-fault.html" title="20.5.4.4 Fault Tolerance for Distributed Recovery">
Section 20.5.4.4, “Fault Tolerance for Distributed Recovery”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_recovery_ssl_ca
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-cloning.html#group-replication-cloning-prerequisites" title="20.5.4.2.1 Prerequisites for Cloning">
Section 20.5.4.2.1, “Prerequisites for Cloning”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-configuring-ssl-for-recovery.html" title="20.6.3.2 Secure Socket Layer (SSL) Connections for Distributed Recovery">
Section 20.6.3.2, “Secure Socket Layer (SSL) Connections for Distributed Recovery”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-distributed-recovery-connections.html#group-replication-distributed-recovery-connections-ssl" title="20.5.4.1.4 SSL and Authentication for Distributed Recovery">
Section 20.5.4.1.4, “SSL and Authentication for Distributed Recovery”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_recovery_ssl_capath
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-configuring-ssl-for-recovery.html" title="20.6.3.2 Secure Socket Layer (SSL) Connections for Distributed Recovery">
Section 20.6.3.2, “Secure Socket Layer (SSL) Connections for Distributed Recovery”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_recovery_ssl_cert
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-cloning.html#group-replication-cloning-prerequisites" title="20.5.4.2.1 Prerequisites for Cloning">
Section 20.5.4.2.1, “Prerequisites for Cloning”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-configuring-ssl-for-recovery.html" title="20.6.3.2 Secure Socket Layer (SSL) Connections for Distributed Recovery">
Section 20.6.3.2, “Secure Socket Layer (SSL) Connections for Distributed Recovery”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-distributed-recovery-connections.html#group-replication-distributed-recovery-connections-ssl" title="20.5.4.1.4 SSL and Authentication for Distributed Recovery">
Section 20.5.4.1.4, “SSL and Authentication for Distributed Recovery”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_recovery_ssl_cipher
</h3>
<dl>
<dt>
<a class="xref" href="encrypted-connection-protocols-ciphers.html" title="8.3.2 Encrypted Connection TLS Protocols and Ciphers">
Section 8.3.2, “Encrypted Connection TLS Protocols and Ciphers”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-configuring-ssl-for-recovery.html" title="20.6.3.2 Secure Socket Layer (SSL) Connections for Distributed Recovery">
Section 20.6.3.2, “Secure Socket Layer (SSL) Connections for Distributed Recovery”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_recovery_ssl_crl
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-configuring-ssl-for-recovery.html" title="20.6.3.2 Secure Socket Layer (SSL) Connections for Distributed Recovery">
Section 20.6.3.2, “Secure Socket Layer (SSL) Connections for Distributed Recovery”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_recovery_ssl_crlpath
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-configuring-ssl-for-recovery.html" title="20.6.3.2 Secure Socket Layer (SSL) Connections for Distributed Recovery">
Section 20.6.3.2, “Secure Socket Layer (SSL) Connections for Distributed Recovery”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_recovery_ssl_key
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-cloning.html#group-replication-cloning-prerequisites" title="20.5.4.2.1 Prerequisites for Cloning">
Section 20.5.4.2.1, “Prerequisites for Cloning”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-configuring-ssl-for-recovery.html" title="20.6.3.2 Secure Socket Layer (SSL) Connections for Distributed Recovery">
Section 20.6.3.2, “Secure Socket Layer (SSL) Connections for Distributed Recovery”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-distributed-recovery-connections.html#group-replication-distributed-recovery-connections-ssl" title="20.5.4.1.4 SSL and Authentication for Distributed Recovery">
Section 20.5.4.1.4, “SSL and Authentication for Distributed Recovery”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_recovery_ssl_verify_server_cert
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-configuring-ssl-for-recovery.html" title="20.6.3.2 Secure Socket Layer (SSL) Connections for Distributed Recovery">
Section 20.6.3.2, “Secure Socket Layer (SSL) Connections for Distributed Recovery”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_recovery_tls_ciphersuites
</h3>
<dl>
<dt>
<a class="xref" href="encrypted-connection-protocols-ciphers.html" title="8.3.2 Encrypted Connection TLS Protocols and Ciphers">
Section 8.3.2, “Encrypted Connection TLS Protocols and Ciphers”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-limitations.html" title="20.3.2 Group Replication Limitations">
Section 20.3.2, “Group Replication Limitations”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-configuring-ssl-for-recovery.html" title="20.6.3.2 Secure Socket Layer (SSL) Connections for Distributed Recovery">
Section 20.6.3.2, “Secure Socket Layer (SSL) Connections for Distributed Recovery”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-secure-socket-layer-support-ssl.html" title="20.6.2 Securing Group Communication Connections with Secure Socket Layer (SSL)">
Section 20.6.2, “Securing Group Communication Connections with Secure Socket Layer (SSL)”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_recovery_tls_version
</h3>
<dl>
<dt>
<a class="xref" href="encrypted-connection-protocols-ciphers.html" title="8.3.2 Encrypted Connection TLS Protocols and Ciphers">
Section 8.3.2, “Encrypted Connection TLS Protocols and Ciphers”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-limitations.html" title="20.3.2 Group Replication Limitations">
Section 20.3.2, “Group Replication Limitations”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-configuring-ssl-for-recovery.html" title="20.6.3.2 Secure Socket Layer (SSL) Connections for Distributed Recovery">
Section 20.6.3.2, “Secure Socket Layer (SSL) Connections for Distributed Recovery”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-secure-socket-layer-support-ssl.html" title="20.6.2 Securing Group Communication Connections with Secure Socket Layer (SSL)">
Section 20.6.2, “Securing Group Communication Connections with Secure Socket Layer (SSL)”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_recovery_use_ssl
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-connection-security.html" title="20.6.1 Communication Stack for Connection Security Management">
Section 20.6.1, “Communication Stack for Connection Security Management”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-cloning.html#group-replication-cloning-prerequisites" title="20.5.4.2.1 Prerequisites for Cloning">
Section 20.5.4.2.1, “Prerequisites for Cloning”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-configuring-ssl-for-recovery.html" title="20.6.3.2 Secure Socket Layer (SSL) Connections for Distributed Recovery">
Section 20.6.3.2, “Secure Socket Layer (SSL) Connections for Distributed Recovery”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-distributed-recovery-connections.html#group-replication-distributed-recovery-connections-ssl" title="20.5.4.1.4 SSL and Authentication for Distributed Recovery">
Section 20.5.4.1.4, “SSL and Authentication for Distributed Recovery”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_recovery_zstd_compression_level
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-distributed-recovery-connections.html#group-replication-recovery-compression" title="20.5.4.1.2 Compression for Distributed Recovery">
Section 20.5.4.1.2, “Compression for Distributed Recovery”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="connection-compression-control.html" title="6.2.8 Connection Compression Control">
Section 6.2.8, “Connection Compression Control”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-message-compression.html" title="20.7.4 Message Compression">
Section 20.7.4, “Message Compression”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log-transaction-compression.html#binary-log-transaction-compression-monitoring" title="7.4.4.5.3 Monitoring Binary Log Transaction Compression">
Section 7.4.4.5.3, “Monitoring Binary Log Transaction Compression”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_single_primary_mode
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-limitations.html" title="20.3.2 Group Replication Limitations">
Section 20.3.2, “Group Replication Limitations”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-deploying-in-multi-primary-or-single-primary-mode.html" title="20.1.3 Multi-Primary and Single-Primary Modes">
Section 20.1.3, “Multi-Primary and Single-Primary Modes”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-multi-primary-mode.html" title="20.1.3.2 Multi-Primary Mode">
Section 20.1.3.2, “Multi-Primary Mode”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-single-primary-mode.html" title="20.1.3.1 Single-Primary Mode">
Section 20.1.3.1, “Single-Primary Mode”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_ssl_mode
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-connection-security.html" title="20.6.1 Communication Stack for Connection Security Management">
Section 20.6.1, “Communication Stack for Connection Security Management”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-secure-user.html#group-replication-secure-user-ssl" title="20.6.3.1.2 Replication User With SSL">
Section 20.6.3.1.2, “Replication User With SSL”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-configuring-ssl-for-recovery.html" title="20.6.3.2 Secure Socket Layer (SSL) Connections for Distributed Recovery">
Section 20.6.3.2, “Secure Socket Layer (SSL) Connections for Distributed Recovery”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-secure-user.html" title="20.6.3.1 Secure User Credentials for Distributed Recovery">
Section 20.6.3.1, “Secure User Credentials for Distributed Recovery”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-distributed-recovery-securing.html" title="20.6.3 Securing Distributed Recovery Connections">
Section 20.6.3, “Securing Distributed Recovery Connections”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-secure-socket-layer-support-ssl.html" title="20.6.2 Securing Group Communication Connections with Secure Socket Layer (SSL)">
Section 20.6.2, “Securing Group Communication Connections with Secure Socket Layer (SSL)”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-distributed-recovery-connections.html#group-replication-distributed-recovery-connections-ssl" title="20.5.4.1.4 SSL and Authentication for Distributed Recovery">
Section 20.5.4.1.4, “SSL and Authentication for Distributed Recovery”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_start_on_boot
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-cloning.html#group-replication-cloning-operations" title="20.5.4.2.3 Cloning Operations">
Section 20.5.4.2.3, “Cloning Operations”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-configuring-instances.html" title="20.2.1.2 Configuring an Instance for Group Replication">
Section 20.2.1.2, “Configuring an Instance for Group Replication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-responses-failure-exit.html" title="20.7.7.4 Exit Action">
Section 20.7.7.4, “Exit Action”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-responses-failure-expel.html" title="20.7.7.1 Expel Timeout">
Section 20.7.7.1, “Expel Timeout”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-frequently-asked-questions.html" title="20.10 Frequently Asked Questions">
Section 20.10, “Frequently Asked Questions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-cloning.html#group-replication-cloning-prerequisites" title="20.5.4.2.1 Prerequisites for Cloning">
Section 20.5.4.2.1, “Prerequisites for Cloning”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-secure-user.html#group-replication-secure-user-provide" title="20.6.3.1.3 Providing Replication User Credentials Securely">
Section 20.6.3.1.3, “Providing Replication User Credentials Securely”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-restarting-group.html" title="20.5.2 Restarting a Group">
Section 20.5.2, “Restarting a Group”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="start-group-replication.html" title="15.4.3.1 START GROUP_REPLICATION Statement">
Section 15.4.3.1, “START GROUP_REPLICATION Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-upgrading-member.html" title="20.8.3.2 Upgrading a Group Replication Member">
Section 20.8.3.2, “Upgrading a Group Replication Member”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-user-credentials.html" title="20.2.1.3 User Credentials For Distributed Recovery">
Section 20.2.1.3, “User Credentials For Distributed Recovery”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_tls_source
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_transaction_size_limit
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-limitations.html" title="20.3.2 Group Replication Limitations">
Section 20.3.2, “Group Replication Limitations”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-performance-message-fragmentation.html" title="20.7.5 Message Fragmentation">
Section 20.7.5, “Message Fragmentation”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_unreachable_majority_timeout
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-responses-failure-exit.html" title="20.7.7.4 Exit Action">
Section 20.7.7.4, “Exit Action”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-network-partitioning.html" title="20.7.8 Handling a Network Partition and Loss of Quorum">
Section 20.7.8, “Handling a Network Partition and Loss of Quorum”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-responses-failure-partition.html" title="20.7.7.2 Unreachable Majority Timeout">
Section 20.7.7.2, “Unreachable Majority Timeout”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
group_replication_view_change_uuid
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-gtids.html" title="20.4.1 GTIDs and Group Replication">
Section 20.4.1, “GTIDs and Group Replication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
gtid_executed
</h3>
<dl>
<dt>
<a class="xref" href="clone-plugin-replication.html" title="7.6.7.7 Cloning for Replication">
Section 7.6.7.7, “Cloning for Replication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="copying-databases.html" title="3.15 Copying MySQL Databases to Another Machine">
Section 3.15, “Copying MySQL Databases to Another Machine”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-snapshot-method.html#replication-howto-mysqldump" title="19.1.2.5.1 Creating a Data Snapshot Using mysqldump">
Section 19.1.2.5.1, “Creating a Data Snapshot Using mysqldump”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysqldump-sql-format.html" title="9.4.1 Dumping Data in SQL Format with mysqldump">
Section 9.4.1, “Dumping Data in SQL Format with mysqldump”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-gtids.html" title="19.1.6.5 Global Transaction ID System Variables">
Section 19.1.6.5, “Global Transaction ID System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-gtids-auto-positioning.html" title="19.1.3.3 GTID Auto-Positioning">
Section 19.1.3.3, “GTID Auto-Positioning”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-gtids-concepts.html" title="19.1.3.1 GTID Format and Storage">
Section 19.1.3.1, “GTID Format and Storage”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-gtids-lifecycle.html" title="19.1.3.2 GTID Life Cycle">
Section 19.1.3.2, “GTID Life Cycle”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysqldump.html" title="6.5.4 mysqldump — A Database Backup Program">
Section 6.5.4, “mysqldump — A Database Backup Program”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-replication-tables.html" title="29.12.11 Performance Schema Replication Tables">
Section 29.12.11, “Performance Schema Replication Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-multi-source-provision-replica.html" title="19.1.5.2 Provisioning a Multi-Source Replica for GTID-Based Replication">
Section 19.1.5.2, “Provisioning a Multi-Source Replica for GTID-Based Replication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-rules-channel-based-filters.html" title="19.2.5.4 Replication Channel Based Filters">
Section 19.2.5.4, “Replication Channel Based Filters”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-gtids-assign-anon.html" title="19.1.3.6 Replication From a Source Without GTIDs to a Replica With GTIDs">
Section 19.1.3.6, “Replication From a Source Without GTIDs to a Replica With GTIDs”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="reset-binary-logs-and-gtids.html" title="15.4.1.2 RESET BINARY LOGS AND GTIDS Statement">
Section 15.4.1.2, “RESET BINARY LOGS AND GTIDS Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-restarting-group.html" title="20.5.2 Restarting a Group">
Section 20.5.2, “Restarting a Group”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-gtids-restrictions.html" title="19.1.3.7 Restrictions on Replication with GTIDs">
Section 19.1.3.7, “Restrictions on Replication with GTIDs”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="show-binary-log-status.html" title="15.7.7.1 SHOW BINARY LOG STATUS Statement">
Section 15.7.7.1, “SHOW BINARY LOG STATUS Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="show-replica-status.html" title="15.7.7.35 SHOW REPLICA STATUS Statement">
Section 15.7.7.35, “SHOW REPLICA STATUS Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-gtids-functions.html" title="19.1.3.8 Stored Function Examples to Manipulate GTIDs">
Section 19.1.3.8, “Stored Function Examples to Manipulate GTIDs”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-log-status-table.html" title="29.12.22.5 The log_status Table">
Section 29.12.22.5, “The log_status Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-cloning.html#group-replication-cloning-threshold" title="20.5.4.2.2 Threshold for Cloning">
Section 20.5.4.2.2, “Threshold for Cloning”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-gtids-failover.html" title="19.1.3.5 Using GTIDs for Failover and Scaleout">
Section 19.1.3.5, “Using GTIDs for Failover and Scaleout”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-enterprise-backup.html" title="20.5.6 Using MySQL Enterprise Backup with Group Replication">
Section 20.5.6, “Using MySQL Enterprise Backup with Group Replication”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
gtid_executed_compression_period
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-gtids.html" title="19.1.6.5 Global Transaction ID System Variables">
Section 19.1.6.5, “Global Transaction ID System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-gtids-concepts.html" title="19.1.3.1 GTID Format and Storage">
Section 19.1.3.1, “GTID Format and Storage”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
GTID_MODE
</h3>
<dl>
<dt>
<a class="xref" href="change-replication-source-to.html" title="15.4.2.2 CHANGE REPLICATION SOURCE TO Statement">
Section 15.4.2.2, “CHANGE REPLICATION SOURCE TO Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-gtids-auto-positioning.html" title="19.1.3.3 GTID Auto-Positioning">
Section 19.1.3.3, “GTID Auto-Positioning”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-transaction-inconsistencies.html" title="19.5.1.34 Replication and Transaction Inconsistencies">
Section 19.5.1.34, “Replication and Transaction Inconsistencies”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
gtid_mode
</h3>
<dl>
<dt>
<a class="xref" href="replication-multi-source-adding-gtid-master.html" title="19.1.5.3 Adding GTID-Based Sources to a Multi-Source Replica">
Section 19.1.5.3, “Adding GTID-Based Sources to a Multi-Source Replica”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-binary-log.html" title="19.1.6.4 Binary Logging Options and Variables">
Section 19.1.6.4, “Binary Logging Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="change-replication-source-to.html" title="15.4.2.2 CHANGE REPLICATION SOURCE TO Statement">
Section 15.4.2.2, “CHANGE REPLICATION SOURCE TO Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="clone-plugin-replication.html" title="7.6.7.7 Cloning for Replication">
Section 7.6.7.7, “Cloning for Replication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="copying-databases.html" title="3.15 Copying MySQL Databases to Another Machine">
Section 3.15, “Copying MySQL Databases to Another Machine”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-snapshot-method.html#replication-howto-mysqldump" title="19.1.2.5.1 Creating a Data Snapshot Using mysqldump">
Section 19.1.2.5.1, “Creating a Data Snapshot Using mysqldump”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-mode-change-online-disable-gtids.html" title="19.1.4.3 Disabling GTID Transactions Online">
Section 19.1.4.3, “Disabling GTID Transactions Online”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysqldump-sql-format.html" title="9.4.1 Dumping Data in SQL Format with mysqldump">
Section 9.4.1, “Dumping Data in SQL Format with mysqldump”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-mode-change-online-enable-gtids.html" title="19.1.4.2 Enabling GTID Transactions Online">
Section 19.1.4.2, “Enabling GTID Transactions Online”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="gtid-functions.html" title="14.18.2 Functions Used with Global Transaction Identifiers (GTIDs)">
Section 14.18.2, “Functions Used with Global Transaction Identifiers (GTIDs)”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-gtids.html" title="19.1.6.5 Global Transaction ID System Variables">
Section 19.1.6.5, “Global Transaction ID System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-requirements.html" title="20.3.1 Group Replication Requirements">
Section 20.3.1, “Group Replication Requirements”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-gtids-concepts.html" title="19.1.3.1 GTID Format and Storage">
Section 19.1.3.1, “GTID Format and Storage”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-gtids.html" title="20.4.1 GTIDs and Group Replication">
Section 20.4.1, “GTIDs and Group Replication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-solutions-unexpected-replica-halt.html" title="19.4.2 Handling an Unexpected Halt of a Replica">
Section 19.4.2, “Handling an Unexpected Halt of a Replica”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysqldump.html" title="6.5.4 mysqldump — A Database Backup Program">
Section 6.5.4, “mysqldump — A Database Backup Program”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-gtids-assign-anon.html" title="19.1.3.6 Replication From a Source Without GTIDs to a Replica With GTIDs">
Section 19.1.3.6, “Replication From a Source Without GTIDs to a Replica With GTIDs”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-mode-change-online-concepts.html" title="19.1.4.1 Replication Mode Concepts">
Section 19.1.4.1, “Replication Mode Concepts”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="reset-binary-logs-and-gtids.html" title="15.4.1.2 RESET BINARY LOGS AND GTIDS Statement">
Section 15.4.1.2, “RESET BINARY LOGS AND GTIDS Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="reset-replica.html" title="15.4.2.3 RESET REPLICA Statement">
Section 15.4.2.3, “RESET REPLICA Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-gtids-howto.html" title="19.1.3.4 Setting Up Replication Using GTIDs">
Section 19.1.3.4, “Setting Up Replication Using GTIDs”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-administration-skip.html" title="19.1.7.3 Skipping Transactions">
Section 19.1.7.3, “Skipping Transactions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-administration-skip.html#replication-administration-skip-gtid" title="19.1.7.3.1 Skipping Transactions With GTIDs">
Section 19.1.7.3.1, “Skipping Transactions With GTIDs”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-administration-skip.html#set-global-replica-sql-skip-counter" title="19.1.7.3.2.1 Skipping Transactions With SET GLOBAL sql_replica_skip_counter">
Section 19.1.7.3.2.1, “Skipping Transactions With
<code class="literal">
SET GLOBAL
sql_replica_skip_counter
</code>
”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-administration-skip.html#replication-administration-skip-nogtid" title="19.1.7.3.2 Skipping Transactions Without GTIDs">
Section 19.1.7.3.2, “Skipping Transactions Without GTIDs”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-asynchronous-connection-failover.html" title="19.4.9 Switching Sources and Replicas with Asynchronous Connection Failover">
Section 19.4.9, “Switching Sources and Replicas with Asynchronous Connection Failover”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-events-transactions-current-table.html" title="29.12.7.1 The events_transactions_current Table">
Section 29.12.7.1, “The events_transactions_current Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="upgrade-binary-package.html" title="3.7 Upgrading MySQL Binary or Package-based Installations on Unix/Linux">
Section 3.7, “Upgrading MySQL Binary or Package-based Installations on Unix/Linux”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-rbr-usage.html" title="19.2.1.2 Usage of Row-Based Logging and Replication">
Section 19.2.1.2, “Usage of Row-Based Logging and Replication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-gtids-failover.html" title="19.1.3.5 Using GTIDs for Failover and Scaleout">
Section 19.1.3.5, “Using GTIDs for Failover and Scaleout”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
gtid_next
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-gtids.html" title="19.1.6.5 Global Transaction ID System Variables">
Section 19.1.6.5, “Global Transaction ID System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-gtids-concepts.html" title="19.1.3.1 GTID Format and Storage">
Section 19.1.3.1, “GTID Format and Storage”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-gtids-lifecycle.html" title="19.1.3.2 GTID Life Cycle">
Section 19.1.3.2, “GTID Life Cycle”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-privilege-checks-account.html" title="19.3.3.1 Privileges For The Replication PRIVILEGE_CHECKS_USER Account">
Section 19.3.3.1, “Privileges For The Replication PRIVILEGE_CHECKS_USER Account”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="privileges-provided.html" title="8.2.2 Privileges Provided by MySQL">
Section 8.2.2, “Privileges Provided by MySQL”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-mode-change-online-concepts.html" title="19.1.4.1 Replication Mode Concepts">
Section 19.1.4.1, “Replication Mode Concepts”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-status-variables.html" title="7.1.10 Server Status Variables">
Section 7.1.10, “Server Status Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="stop-replica.html" title="15.4.2.5 STOP REPLICA Statement">
Section 15.4.2.5, “STOP REPLICA Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-events-transactions-current-table.html" title="29.12.7.1 The events_transactions_current Table">
Section 29.12.7.1, “The events_transactions_current Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
gtid_owned
</h3>
<dl>
<dt>
<a class="xref" href="replication-mode-change-online-disable-gtids.html" title="19.1.4.3 Disabling GTID Transactions Online">
Section 19.1.4.3, “Disabling GTID Transactions Online”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-gtids.html" title="19.1.6.5 Global Transaction ID System Variables">
Section 19.1.6.5, “Global Transaction ID System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-gtids-lifecycle.html" title="19.1.3.2 GTID Life Cycle">
Section 19.1.3.2, “GTID Life Cycle”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
gtid_purged
</h3>
<dl>
<dt>
<a class="xref" href="change-replication-source-to.html" title="15.4.2.2 CHANGE REPLICATION SOURCE TO Statement">
Section 15.4.2.2, “CHANGE REPLICATION SOURCE TO Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-snapshot-method.html#replication-howto-mysqldump" title="19.1.2.5.1 Creating a Data Snapshot Using mysqldump">
Section 19.1.2.5.1, “Creating a Data Snapshot Using mysqldump”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysqldump-sql-format.html" title="9.4.1 Dumping Data in SQL Format with mysqldump">
Section 9.4.1, “Dumping Data in SQL Format with mysqldump”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-gtids.html" title="19.1.6.5 Global Transaction ID System Variables">
Section 19.1.6.5, “Global Transaction ID System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-gtids-auto-positioning.html" title="19.1.3.3 GTID Auto-Positioning">
Section 19.1.3.3, “GTID Auto-Positioning”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-gtids-concepts.html" title="19.1.3.1 GTID Format and Storage">
Section 19.1.3.1, “GTID Format and Storage”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-gtids-lifecycle.html" title="19.1.3.2 GTID Life Cycle">
Section 19.1.3.2, “GTID Life Cycle”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysqldump.html" title="6.5.4 mysqldump — A Database Backup Program">
Section 6.5.4, “mysqldump — A Database Backup Program”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="privileges-provided.html" title="8.2.2 Privileges Provided by MySQL">
Section 8.2.2, “Privileges Provided by MySQL”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-multi-source-provision-replica.html" title="19.1.5.2 Provisioning a Multi-Source Replica for GTID-Based Replication">
Section 19.1.5.2, “Provisioning a Multi-Source Replica for GTID-Based Replication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="reset-binary-logs-and-gtids.html" title="15.4.1.2 RESET BINARY LOGS AND GTIDS Statement">
Section 15.4.1.2, “RESET BINARY LOGS AND GTIDS Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-gtids-functions.html" title="19.1.3.8 Stored Function Examples to Manipulate GTIDs">
Section 19.1.3.8, “Stored Function Examples to Manipulate GTIDs”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-cloning.html#group-replication-cloning-threshold" title="20.5.4.2.2 Threshold for Cloning">
Section 20.5.4.2.2, “Threshold for Cloning”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-gtids-failover.html" title="19.1.3.5 Using GTIDs for Failover and Scaleout">
Section 19.1.3.5, “Using GTIDs for Failover and Scaleout”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<a name="sysvar-index-H">
</a>
<h3 class="title">
H
</h3>
<p>
[
<a class="link" href="dynindex-sysvar.html#sysvar-index-top">
index top
</a>
]
</p>
<dl>
<dt>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
have_compress
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
have_dynamic_loading
</h3>
<dl>
<dt>
<a class="xref" href="replication-semisync-installation.html" title="19.4.10.1 Installing Semisynchronous Replication">
Section 19.4.10.1, “Installing Semisynchronous Replication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
have_geometry
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
have_profiling
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
have_query_cache
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
have_rtree_keys
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
have_statement_timeout
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
have_symlink
</h3>
<dl>
<dt>
<a class="xref" href="server-options.html" title="7.1.7 Server Command Options">
Section 7.1.7, “Server Command Options”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="windows-symbolic-links.html" title="10.12.2.3 Using Symbolic Links for Databases on Windows">
Section 10.12.2.3, “Using Symbolic Links for Databases on Windows”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="symbolic-links-to-tables.html" title="10.12.2.2 Using Symbolic Links for MyISAM Tables on Unix">
Section 10.12.2.2, “Using Symbolic Links for MyISAM Tables on Unix”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
histogram_generation_max_mem_size
</h3>
<dl>
<dt>
<a class="xref" href="analyze-table.html" title="15.7.3.1 ANALYZE TABLE Statement">
Section 15.7.3.1, “ANALYZE TABLE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
host_cache_size
</h3>
<dl>
<dt>
<a class="xref" href="host-cache.html" title="7.1.12.3 DNS Lookups and the Host Cache">
Section 7.1.12.3, “DNS Lookups and the Host Cache”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-host-cache-table.html" title="29.12.22.3 The host_cache Table">
Section 29.12.22.3, “The host_cache Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
hostname
</h3>
<dl>
<dt>
<a class="xref" href="clone.html" title="15.7.5 CLONE Statement">
Section 15.7.5, “CLONE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="clone-plugin-remote.html" title="7.6.7.3 Cloning Remote Data">
Section 7.6.7.3, “Cloning Remote Data”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-configuring-instances.html" title="20.2.1.2 Configuring an Instance for Group Replication">
Section 20.2.1.2, “Configuring an Instance for Group Replication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-distributed-recovery-connections.html" title="20.5.4.1 Connections for Distributed Recovery">
Section 20.5.4.1, “Connections for Distributed Recovery”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-frequently-asked-questions.html" title="20.10 Frequently Asked Questions">
Section 20.10, “Frequently Asked Questions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-distributed-recovery-securing.html" title="20.6.3 Securing Distributed Recovery Connections">
Section 20.6.3, “Securing Distributed Recovery Connections”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-replication-group-members-table.html" title="29.12.11.16 The replication_group_members Table">
Section 29.12.11.16, “The replication_group_members Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<a name="sysvar-index-I">
</a>
<h3 class="title">
I
</h3>
<p>
[
<a class="link" href="dynindex-sysvar.html#sysvar-index-top">
index top
</a>
]
</p>
<dl>
<dt>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
identity
</h3>
<dl>
<dt>
<a class="xref" href="binary-log-mixed.html" title="7.4.4.3 Mixed Binary Logging Format">
Section 7.4.4.3, “Mixed Binary Logging Format”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-variables.html" title="19.5.1.39 Replication and Variables">
Section 19.5.1.39, “Replication and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
immediate_server_version
</h3>
<dl>
<dt>
<a class="xref" href="replication-privilege-checks-account.html" title="19.3.3.1 Privileges For The Replication PRIVILEGE_CHECKS_USER Account">
Section 19.3.3.1, “Privileges For The Replication PRIVILEGE_CHECKS_USER Account”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-compatibility.html" title="19.5.2 Replication Compatibility Between MySQL Versions">
Section 19.5.2, “Replication Compatibility Between MySQL Versions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-source.html" title="19.1.6.2 Replication Source Options and Variables">
Section 19.1.6.2, “Replication Source Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
information_schema_stats_expiry
</h3>
<dl>
<dt>
<a class="xref" href="analyze-table.html" title="15.7.3.1 ANALYZE TABLE Statement">
Section 15.7.3.1, “ANALYZE TABLE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="data-dictionary-usage-differences.html" title="16.7 Data Dictionary Usage Differences">
Section 16.7, “Data Dictionary Usage Differences”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="data-dictionary-information-schema.html" title="16.5 INFORMATION_SCHEMA and Data Dictionary Integration">
Section 16.5, “INFORMATION_SCHEMA and Data Dictionary Integration”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-optimization.html" title="10.2.3 Optimizing INFORMATION_SCHEMA Queries">
Section 10.2.3, “Optimizing INFORMATION_SCHEMA Queries”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-statistics-table.html" title="28.3.34 The INFORMATION_SCHEMA STATISTICS Table">
Section 28.3.34, “The INFORMATION_SCHEMA STATISTICS Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-tables-table.html" title="28.3.38 The INFORMATION_SCHEMA TABLES Table">
Section 28.3.38, “The INFORMATION_SCHEMA TABLES Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
init_connect
</h3>
<dl>
<dt>
<a class="xref" href="charset-applications.html" title="12.5 Configuring Application Character Set and Collation">
Section 12.5, “Configuring Application Character Set and Collation”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="privileges-provided.html" title="8.2.2 Privileges Provided by MySQL">
Section 8.2.2, “Privileges Provided by MySQL”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-host-cache-table.html" title="29.12.22.3 The host_cache Table">
Section 29.12.22.3, “The host_cache Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
init_file
</h3>
<dl>
<dt>
<a class="xref" href="alter-database.html" title="15.1.2 ALTER DATABASE Statement">
Section 15.1.2, “ALTER DATABASE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="data-directory-initialization.html" title="2.9.1 Initializing the Data Directory">
Section 2.9.1, “Initializing the Data Directory”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="multiple-key-caches.html" title="10.10.2.2 Multiple Key Caches">
Section 10.10.2.2, “Multiple Key Caches”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-runtime-configuration.html" title="29.4 Performance Schema Runtime Configuration">
Section 29.4, “Performance Schema Runtime Configuration”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-variables-info-table.html" title="29.12.14.2 Performance Schema variables_info Table">
Section 29.12.14.2, “Performance Schema variables_info Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-memory.html" title="19.5.1.21 Replication and MEMORY Tables">
Section 19.5.1.21, “Replication and MEMORY Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="resetting-permissions.html#resetting-permissions-unix" title="B.3.3.2.2 Resetting the Root Password: Unix and Unix-Like Systems">
Section B.3.3.2.2, “Resetting the Root Password: Unix and Unix-Like Systems”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="resetting-permissions.html#resetting-permissions-windows" title="B.3.3.2.1 Resetting the Root Password: Windows Systems">
Section B.3.3.2.1, “Resetting the Root Password: Windows Systems”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-options.html" title="7.1.7 Server Command Options">
Section 7.1.7, “Server Command Options”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="memory-storage-engine.html" title="18.3 The MEMORY Storage Engine">
Section 18.3, “The MEMORY Storage Engine”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
init_replica
</h3>
<dl>
<dt>
<a class="xref" href="replication-privilege-checks-account.html" title="19.3.3.1 Privileges For The Replication PRIVILEGE_CHECKS_USER Account">
Section 19.3.3.1, “Privileges For The Replication PRIVILEGE_CHECKS_USER Account”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
init_slave
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb
</h3>
<dl>
<dt>
<a class="xref" href="innodb-read-only-instance.html" title="17.8.2 Configuring InnoDB for Read-Only Operation">
Section 17.8.2, “Configuring InnoDB for Read-Only Operation”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-buffer-pool-in-core-file.html" title="17.8.3.7 Excluding or Including Buffer Pool Pages from Core Files">
Section 17.8.3.7, “Excluding or Including Buffer Pool Pages from Core Files”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="faqs-innodb-change-buffer.html" title="A.16 MySQL 8.4 FAQ: InnoDB Change Buffer">
Section A.16, “MySQL 8.4 FAQ: InnoDB Change Buffer”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_adaptive_flushing
</h3>
<dl>
<dt>
<a class="xref" href="innodb-buffer-pool-flushing.html" title="17.8.3.5 Configuring Buffer Pool Flushing">
Section 17.8.3.5, “Configuring Buffer Pool Flushing”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_adaptive_flushing_lwm
</h3>
<dl>
<dt>
<a class="xref" href="innodb-buffer-pool-flushing.html" title="17.8.3.5 Configuring Buffer Pool Flushing">
Section 17.8.3.5, “Configuring Buffer Pool Flushing”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_adaptive_hash_index
</h3>
<dl>
<dt>
<a class="xref" href="innodb-adaptive-hash.html" title="17.5.3 Adaptive Hash Index">
Section 17.5.3, “Adaptive Hash Index”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-performance-thread_concurrency.html" title="17.8.4 Configuring Thread Concurrency for InnoDB">
Section 17.8.4, “Configuring Thread Concurrency for InnoDB”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="glossary.html" title="MySQL Glossary">
MySQL Glossary
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="optimizing-innodb-configuration-variables.html" title="10.5.9 Optimizing InnoDB Configuration Variables">
Section 10.5.9, “Optimizing InnoDB Configuration Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_adaptive_hash_index_parts
</h3>
<dl>
<dt>
<a class="xref" href="innodb-adaptive-hash.html" title="17.5.3 Adaptive Hash Index">
Section 17.5.3, “Adaptive Hash Index”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-innodb-trx-table.html" title="28.4.28 The INFORMATION_SCHEMA INNODB_TRX Table">
Section 28.4.28, “The INFORMATION_SCHEMA INNODB_TRX Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_adaptive_max_sleep_delay
</h3>
<dl>
<dt>
<a class="xref" href="innodb-performance-thread_concurrency.html" title="17.8.4 Configuring Thread Concurrency for InnoDB">
Section 17.8.4, “Configuring Thread Concurrency for InnoDB”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_autoextend_increment
</h3>
<dl>
<dt>
<a class="xref" href="innodb-file-per-table-tablespaces.html" title="17.6.3.2 File-Per-Table Tablespaces">
Section 17.6.3.2, “File-Per-Table Tablespaces”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-init-startup-configuration.html" title="17.8.1 InnoDB Startup Configuration">
Section 17.8.1, “InnoDB Startup Configuration”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="glossary.html" title="MySQL Glossary">
MySQL Glossary
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-system-tablespace.html" title="17.6.3.1 The System Tablespace">
Section 17.6.3.1, “The System Tablespace”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_autoinc_lock_mode
</h3>
<dl>
<dt>
<a class="xref" href="innodb-auto-increment-handling.html" title="17.6.1.6 AUTO_INCREMENT Handling in InnoDB">
Section 17.6.1.6, “AUTO_INCREMENT Handling in InnoDB”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="optimizing-innodb-bulk-data-loading.html" title="10.5.5 Bulk Data Loading for InnoDB Tables">
Section 10.5.5, “Bulk Data Loading for InnoDB Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-functions.html" title="14.15 Information Functions">
Section 14.15, “Information Functions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-locking.html" title="17.7.1 InnoDB Locking">
Section 17.7.1, “InnoDB Locking”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-locks-set.html" title="17.7.3 Locks Set by Different SQL Statements in InnoDB">
Section 17.7.3, “Locks Set by Different SQL Statements in InnoDB”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="glossary.html" title="MySQL Glossary">
MySQL Glossary
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_background_drop_list_empty
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_buffer_pool_chunk_size
</h3>
<dl>
<dt>
<a class="xref" href="innodb-buffer-pool-resize.html" title="17.8.3.1 Configuring InnoDB Buffer Pool Size">
Section 17.8.3.1, “Configuring InnoDB Buffer Pool Size”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="large-page-support.html" title="10.12.3.3 Enabling Large Page Support">
Section 10.12.3.3, “Enabling Large Page Support”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_buffer_pool_debug
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_buffer_pool_dump_at_shutdown
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="glossary.html" title="MySQL Glossary">
MySQL Glossary
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-preload-buffer-pool.html" title="17.8.3.6 Saving and Restoring the Buffer Pool State">
Section 17.8.3.6, “Saving and Restoring the Buffer Pool State”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_buffer_pool_dump_now
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-preload-buffer-pool.html" title="17.8.3.6 Saving and Restoring the Buffer Pool State">
Section 17.8.3.6, “Saving and Restoring the Buffer Pool State”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_buffer_pool_dump_pct
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-preload-buffer-pool.html" title="17.8.3.6 Saving and Restoring the Buffer Pool State">
Section 17.8.3.6, “Saving and Restoring the Buffer Pool State”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_buffer_pool_filename
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-preload-buffer-pool.html" title="17.8.3.6 Saving and Restoring the Buffer Pool State">
Section 17.8.3.6, “Saving and Restoring the Buffer Pool State”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_buffer_pool_in_core_file
</h3>
<dl>
<dt>
<a class="xref" href="innodb-buffer-pool-in-core-file.html" title="17.8.3.7 Excluding or Including Buffer Pool Pages from Core Files">
Section 17.8.3.7, “Excluding or Including Buffer Pool Pages from Core Files”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysqld-safe.html" title="6.3.2 mysqld_safe — MySQL Server Startup Script">
Section 6.3.2, “mysqld_safe — MySQL Server Startup Script”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-options.html" title="7.1.7 Server Command Options">
Section 7.1.7, “Server Command Options”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_buffer_pool_instances
</h3>
<dl>
<dt>
<a class="xref" href="innodb-buffer-pool-flushing.html" title="17.8.3.5 Configuring Buffer Pool Flushing">
Section 17.8.3.5, “Configuring Buffer Pool Flushing”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-buffer-pool-resize.html" title="17.8.3.1 Configuring InnoDB Buffer Pool Size">
Section 17.8.3.1, “Configuring InnoDB Buffer Pool Size”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-multiple-buffer-pools.html" title="17.8.3.2 Configuring Multiple Buffer Pool Instances">
Section 17.8.3.2, “Configuring Multiple Buffer Pool Instances”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-doublewrite-buffer.html" title="17.6.4 Doublewrite Buffer">
Section 17.6.4, “Doublewrite Buffer”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="memory-use.html" title="10.12.3.1 How MySQL Uses Memory">
Section 10.12.3.1, “How MySQL Uses Memory”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-init-startup-configuration.html" title="17.8.1 InnoDB Startup Configuration">
Section 17.8.1, “InnoDB Startup Configuration”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="glossary.html" title="MySQL Glossary">
MySQL Glossary
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_buffer_pool_load_abort
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-status-variables.html" title="7.1.10 Server Status Variables">
Section 7.1.10, “Server Status Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_buffer_pool_load_at_startup
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="glossary.html" title="MySQL Glossary">
MySQL Glossary
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-preload-buffer-pool.html" title="17.8.3.6 Saving and Restoring the Buffer Pool State">
Section 17.8.3.6, “Saving and Restoring the Buffer Pool State”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-status-variables.html" title="7.1.10 Server Status Variables">
Section 7.1.10, “Server Status Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_buffer_pool_load_now
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-preload-buffer-pool.html" title="17.8.3.6 Saving and Restoring the Buffer Pool State">
Section 17.8.3.6, “Saving and Restoring the Buffer Pool State”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-status-variables.html" title="7.1.10 Server Status Variables">
Section 7.1.10, “Server Status Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_buffer_pool_size
</h3>
<dl>
<dt>
<a class="xref" href="innodb-performance-compression-oltp.html" title="17.9.1.6 Compression for OLTP Workloads">
Section 17.9.1.6, “Compression for OLTP Workloads”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-buffer-pool-resize.html" title="17.8.3.1 Configuring InnoDB Buffer Pool Size">
Section 17.8.3.1, “Configuring InnoDB Buffer Pool Size”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-multiple-buffer-pools.html" title="17.8.3.2 Configuring Multiple Buffer Pool Instances">
Section 17.8.3.2, “Configuring Multiple Buffer Pool Instances”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="converting-tables-to-innodb.html" title="17.6.1.5 Converting Tables from MyISAM to InnoDB">
Section 17.6.1.5, “Converting Tables from MyISAM to InnoDB”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-dedicated-server.html" title="17.8.12 Enabling Automatic InnoDB Configuration for a Dedicated MySQL Server">
Section 17.8.12, “Enabling Automatic InnoDB Configuration for a Dedicated MySQL Server”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="large-page-support.html" title="10.12.3.3 Enabling Large Page Support">
Section 10.12.3.3, “Enabling Large Page Support”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="memory-use.html" title="10.12.3.1 How MySQL Uses Memory">
Section 10.12.3.1, “How MySQL Uses Memory”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-init-startup-configuration.html" title="17.8.1 InnoDB Startup Configuration">
Section 17.8.1, “InnoDB Startup Configuration”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="glossary.html" title="MySQL Glossary">
MySQL Glossary
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="optimizing-innodb-diskio.html" title="10.5.8 Optimizing InnoDB Disk I/O">
Section 10.5.8, “Optimizing InnoDB Disk I/O”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-status-variables.html" title="7.1.10 Server Status Variables">
Section 7.1.10, “Server Status Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_change_buffer_max_size
</h3>
<dl>
<dt>
<a class="xref" href="innodb-change-buffer.html" title="17.5.2 Change Buffer">
Section 17.5.2, “Change Buffer”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="faqs-innodb-change-buffer.html" title="A.16 MySQL 8.4 FAQ: InnoDB Change Buffer">
Section A.16, “MySQL 8.4 FAQ: InnoDB Change Buffer”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="glossary.html" title="MySQL Glossary">
MySQL Glossary
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_change_buffering
</h3>
<dl>
<dt>
<a class="xref" href="innodb-change-buffer.html" title="17.5.2 Change Buffer">
Section 17.5.2, “Change Buffer”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-read-only-instance.html" title="17.8.2 Configuring InnoDB for Read-Only Operation">
Section 17.8.2, “Configuring InnoDB for Read-Only Operation”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="glossary.html" title="MySQL Glossary">
MySQL Glossary
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="optimizing-innodb-transaction-management.html" title="10.5.2 Optimizing InnoDB Transaction Management">
Section 10.5.2, “Optimizing InnoDB Transaction Management”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_change_buffering_debug
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_checkpoint_disabled
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_checksum_algorithm
</h3>
<dl>
<dt>
<a class="xref" href="innodb-benefits.html" title="17.1.1 Benefits of Using InnoDB Tables">
Section 17.1.1, “Benefits of Using InnoDB Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="glossary.html" title="MySQL Glossary">
MySQL Glossary
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="optimizing-innodb-diskio.html" title="10.5.8 Optimizing InnoDB Disk I/O">
Section 10.5.8, “Optimizing InnoDB Disk I/O”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_cmp_per_index_enabled
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-compression-tuning-monitoring.html" title="17.9.1.4 Monitoring InnoDB Table Compression at Runtime">
Section 17.9.1.4, “Monitoring InnoDB Table Compression at Runtime”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-innodb-cmp-per-index-table.html" title="28.4.8 The INFORMATION_SCHEMA INNODB_CMP_PER_INDEX and INNODB_CMP_PER_INDEX_RESET Tables">
Section 28.4.8, “The INFORMATION_SCHEMA INNODB_CMP_PER_INDEX and
INNODB_CMP_PER_INDEX_RESET Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-compression-tuning.html" title="17.9.1.3 Tuning Compression for InnoDB Tables">
Section 17.9.1.3, “Tuning Compression for InnoDB Tables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_commit_concurrency
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_compress_debug
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_compression_failure_threshold_pct
</h3>
<dl>
<dt>
<a class="xref" href="innodb-performance-compression-oltp.html" title="17.9.1.6 Compression for OLTP Workloads">
Section 17.9.1.6, “Compression for OLTP Workloads”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-compression-internals.html" title="17.9.1.5 How Compression Works for InnoDB Tables">
Section 17.9.1.5, “How Compression Works for InnoDB Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="glossary.html" title="MySQL Glossary">
MySQL Glossary
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-compression-tuning.html" title="17.9.1.3 Tuning Compression for InnoDB Tables">
Section 17.9.1.3, “Tuning Compression for InnoDB Tables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_compression_level
</h3>
<dl>
<dt>
<a class="xref" href="innodb-performance-compression-oltp.html" title="17.9.1.6 Compression for OLTP Workloads">
Section 17.9.1.6, “Compression for OLTP Workloads”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-compression-internals.html" title="17.9.1.5 How Compression Works for InnoDB Tables">
Section 17.9.1.5, “How Compression Works for InnoDB Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="glossary.html" title="MySQL Glossary">
MySQL Glossary
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-compression-tuning.html" title="17.9.1.3 Tuning Compression for InnoDB Tables">
Section 17.9.1.3, “Tuning Compression for InnoDB Tables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_compression_pad_pct_max
</h3>
<dl>
<dt>
<a class="xref" href="innodb-performance-compression-oltp.html" title="17.9.1.6 Compression for OLTP Workloads">
Section 17.9.1.6, “Compression for OLTP Workloads”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-compression-internals.html" title="17.9.1.5 How Compression Works for InnoDB Tables">
Section 17.9.1.5, “How Compression Works for InnoDB Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="glossary.html" title="MySQL Glossary">
MySQL Glossary
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-compression-tuning.html" title="17.9.1.3 Tuning Compression for InnoDB Tables">
Section 17.9.1.3, “Tuning Compression for InnoDB Tables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_concurrency_tickets
</h3>
<dl>
<dt>
<a class="xref" href="innodb-performance-thread_concurrency.html" title="17.8.4 Configuring Thread Concurrency for InnoDB">
Section 17.8.4, “Configuring Thread Concurrency for InnoDB”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="optimizing-innodb-configuration-variables.html" title="10.5.9 Optimizing InnoDB Configuration Variables">
Section 10.5.9, “Optimizing InnoDB Configuration Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-innodb-trx-table.html" title="28.4.28 The INFORMATION_SCHEMA INNODB_TRX Table">
Section 28.4.28, “The INFORMATION_SCHEMA INNODB_TRX Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_data_file_path
</h3>
<dl>
<dt>
<a class="xref" href="clone-plugin-remote.html" title="7.6.7.3 Cloning Remote Data">
Section 7.6.7.3, “Cloning Remote Data”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-file-space.html" title="17.11.2 File Space Management">
Section 17.11.2, “File Space Management”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="data-directory-initialization.html" title="2.9.1 Initializing the Data Directory">
Section 2.9.1, “Initializing the Data Directory”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innochecksum.html" title="6.6.2 innochecksum — Offline InnoDB File Checksum Utility">
Section 6.6.2, “innochecksum — Offline InnoDB File Checksum Utility”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-init-startup-configuration.html" title="17.8.1 InnoDB Startup Configuration">
Section 17.8.1, “InnoDB Startup Configuration”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-files-table.html" title="28.3.15 The INFORMATION_SCHEMA FILES Table">
Section 28.3.15, “The INFORMATION_SCHEMA FILES Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-system-tablespace.html" title="17.6.3.1 The System Tablespace">
Section 17.6.3.1, “The System Tablespace”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="error-creating-innodb.html" title="17.20.1 Troubleshooting InnoDB I/O Problems">
Section 17.20.1, “Troubleshooting InnoDB I/O Problems”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_data_home_dir
</h3>
<dl>
<dt>
<a class="xref" href="clone-plugin-remote.html" title="7.6.7.3 Cloning Remote Data">
Section 7.6.7.3, “Cloning Remote Data”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-create-table-external.html" title="17.6.1.2 Creating Tables Externally">
Section 17.6.1.2, “Creating Tables Externally”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-doublewrite-buffer.html" title="17.6.4 Doublewrite Buffer">
Section 17.6.4, “Doublewrite Buffer”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="general-tablespaces.html" title="17.6.3.3 General Tablespaces">
Section 17.6.3.3, “General Tablespaces”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="data-directory-initialization.html" title="2.9.1 Initializing the Data Directory">
Section 2.9.1, “Initializing the Data Directory”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-recovery.html" title="17.18.2 InnoDB Recovery">
Section 17.18.2, “InnoDB Recovery”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-init-startup-configuration.html" title="17.8.1 InnoDB Startup Configuration">
Section 17.8.1, “InnoDB Startup Configuration”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-moving-data-files-offline.html" title="17.6.3.6 Moving Tablespace Files While the Server is Offline">
Section 17.6.3.6, “Moving Tablespace Files While the Server is Offline”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-redo-log.html" title="17.6.5 Redo Log">
Section 17.6.5, “Redo Log”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-temporary-tablespace.html" title="17.6.3.5 Temporary Tablespaces">
Section 17.6.3.5, “Temporary Tablespaces”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="error-creating-innodb.html" title="17.20.1 Troubleshooting InnoDB I/O Problems">
Section 17.20.1, “Troubleshooting InnoDB I/O Problems”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="truncate-table.html" title="15.1.37 TRUNCATE TABLE Statement">
Section 15.1.37, “TRUNCATE TABLE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-undo-tablespaces.html" title="17.6.3.4 Undo Tablespaces">
Section 17.6.3.4, “Undo Tablespaces”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-enterprise-backup.html" title="20.5.6 Using MySQL Enterprise Backup with Group Replication">
Section 20.5.6, “Using MySQL Enterprise Backup with Group Replication”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_ddl_buffer_size
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="online-ddl-memory-management.html" title="17.12.4 Online DDL Memory Management">
Section 17.12.4, “Online DDL Memory Management”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_ddl_log_crash_reset_debug
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_ddl_threads
</h3>
<dl>
<dt>
<a class="xref" href="online-ddl-parallel-thread-configuration.html" title="17.12.5 Configuring Parallel Threads for Online DDL Operations">
Section 17.12.5, “Configuring Parallel Threads for Online DDL Operations”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="online-ddl-memory-management.html" title="17.12.4 Online DDL Memory Management">
Section 17.12.4, “Online DDL Memory Management”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_deadlock_detect
</h3>
<dl>
<dt>
<a class="xref" href="converting-tables-to-innodb.html" title="17.6.1.5 Converting Tables from MyISAM to InnoDB">
Section 17.6.1.5, “Converting Tables from MyISAM to InnoDB”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-deadlock-detection.html" title="17.7.5.2 Deadlock Detection">
Section 17.7.5.2, “Deadlock Detection”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-deadlocks.html" title="17.7.5 Deadlocks in InnoDB">
Section 17.7.5, “Deadlocks in InnoDB”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="internal-locking.html" title="10.11.1 Internal Locking Methods">
Section 10.11.1, “Internal Locking Methods”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="glossary.html" title="MySQL Glossary">
MySQL Glossary
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_default_row_format
</h3>
<dl>
<dt>
<a class="xref" href="create-table.html" title="15.1.20 CREATE TABLE Statement">
Section 15.1.20, “CREATE TABLE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="using-innodb-tables.html" title="17.6.1.1 Creating InnoDB Tables">
Section 17.6.1.1, “Creating InnoDB Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-table-import.html" title="17.6.1.3 Importing InnoDB Tables">
Section 17.6.1.3, “Importing InnoDB Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-row-format.html" title="17.10 InnoDB Row Formats">
Section 17.10, “InnoDB Row Formats”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="glossary.html" title="MySQL Glossary">
MySQL Glossary
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="data-size.html" title="10.4.1 Optimizing Data Size">
Section 10.4.1, “Optimizing Data Size”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_directories
</h3>
<dl>
<dt>
<a class="xref" href="create-tablespace.html" title="15.1.21 CREATE TABLESPACE Statement">
Section 15.1.21, “CREATE TABLESPACE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-create-table-external.html" title="17.6.1.2 Creating Tables Externally">
Section 17.6.1.2, “Creating Tables Externally”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-disabling-tablespace-path-validation.html" title="17.6.3.7 Disabling Tablespace Path Validation">
Section 17.6.3.7, “Disabling Tablespace Path Validation”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="general-tablespaces.html" title="17.6.3.3 General Tablespaces">
Section 17.6.3.3, “General Tablespaces”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-recovery.html" title="17.18.2 InnoDB Recovery">
Section 17.18.2, “InnoDB Recovery”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-moving-data-files-offline.html" title="17.6.3.6 Moving Tablespace Files While the Server is Offline">
Section 17.6.3.6, “Moving Tablespace Files While the Server is Offline”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-redo-log.html" title="17.6.5 Redo Log">
Section 17.6.5, “Redo Log”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="truncate-table.html" title="15.1.37 TRUNCATE TABLE Statement">
Section 15.1.37, “TRUNCATE TABLE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-undo-tablespaces.html" title="17.6.3.4 Undo Tablespaces">
Section 17.6.3.4, “Undo Tablespaces”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_disable_sort_file_cache
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_doublewrite
</h3>
<dl>
<dt>
<a class="xref" href="innodb-doublewrite-buffer.html" title="17.6.4 Doublewrite Buffer">
Section 17.6.4, “Doublewrite Buffer”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-disk-io.html" title="17.11.1 InnoDB Disk I/O">
Section 17.11.1, “InnoDB Disk I/O”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-init-startup-configuration.html" title="17.8.1 InnoDB Startup Configuration">
Section 17.8.1, “InnoDB Startup Configuration”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_doublewrite_batch_size
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_doublewrite_dir
</h3>
<dl>
<dt>
<a class="xref" href="innodb-doublewrite-buffer.html" title="17.6.4 Doublewrite Buffer">
Section 17.6.4, “Doublewrite Buffer”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-init-startup-configuration.html" title="17.8.1 InnoDB Startup Configuration">
Section 17.8.1, “InnoDB Startup Configuration”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_doublewrite_files
</h3>
<dl>
<dt>
<a class="xref" href="innodb-doublewrite-buffer.html" title="17.6.4 Doublewrite Buffer">
Section 17.6.4, “Doublewrite Buffer”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_doublewrite_pages
</h3>
<dl>
<dt>
<a class="xref" href="innodb-doublewrite-buffer.html" title="17.6.4 Doublewrite Buffer">
Section 17.6.4, “Doublewrite Buffer”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_extend_and_initialize
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-optimize-tablespace-page-allocation.html" title="17.6.3.8 Optimizing Tablespace Space Allocation on Linux">
Section 17.6.3.8, “Optimizing Tablespace Space Allocation on Linux”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_fast_shutdown
</h3>
<dl>
<dt>
<a class="xref" href="innodb-recovery.html" title="17.18.2 InnoDB Recovery">
Section 17.18.2, “InnoDB Recovery”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="glossary.html" title="MySQL Glossary">
MySQL Glossary
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="upgrade-prerequisites.html" title="3.6 Preparing Your Installation for Upgrade">
Section 3.6, “Preparing Your Installation for Upgrade”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-shutdown.html" title="7.1.19 The Server Shutdown Process">
Section 7.1.19, “The Server Shutdown Process”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="upgrade-troubleshooting.html" title="3.13 Upgrade Troubleshooting">
Section 3.13, “Upgrade Troubleshooting”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="upgrade-binary-package.html" title="3.7 Upgrading MySQL Binary or Package-based Installations on Unix/Linux">
Section 3.7, “Upgrading MySQL Binary or Package-based Installations on Unix/Linux”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_fil_make_page_dirty_debug
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_file_per
</h3>
<dl>
<dt>
<a class="xref" href="create-temporary-table.html" title="15.1.20.2 CREATE TEMPORARY TABLE Statement">
Section 15.1.20.2, “CREATE TEMPORARY TABLE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_file_per_table
</h3>
<dl>
<dt>
<a class="xref" href="innodb-best-practices.html" title="17.1.2 Best Practices for InnoDB Tables">
Section 17.1.2, “Best Practices for InnoDB Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="converting-tables-to-innodb.html" title="17.6.1.5 Converting Tables from MyISAM to InnoDB">
Section 17.6.1.5, “Converting Tables from MyISAM to InnoDB”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="create-table.html" title="15.1.20 CREATE TABLE Statement">
Section 15.1.20, “CREATE TABLE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="create-tablespace.html" title="15.1.21 CREATE TABLESPACE Statement">
Section 15.1.21, “CREATE TABLESPACE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-compression-usage.html" title="17.9.1.2 Creating Compressed Tables">
Section 17.9.1.2, “Creating Compressed Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="using-innodb-tables.html" title="17.6.1.1 Creating InnoDB Tables">
Section 17.6.1.1, “Creating InnoDB Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-create-table-external.html" title="17.6.1.2 Creating Tables Externally">
Section 17.6.1.2, “Creating Tables Externally”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-file-space.html" title="17.11.2 File Space Management">
Section 17.11.2, “File Space Management”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-file-per-table-tablespaces.html" title="17.6.3.2 File-Per-Table Tablespaces">
Section 17.6.3.2, “File-Per-Table Tablespaces”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="create-table-files.html" title="15.1.20.1 Files Created by CREATE TABLE">
Section 15.1.20.1, “Files Created by CREATE TABLE”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="flush.html" title="15.7.8.3 FLUSH Statement">
Section 15.7.8.3, “FLUSH Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-compression-internals.html" title="17.9.1.5 How Compression Works for InnoDB Tables">
Section 17.9.1.5, “How Compression Works for InnoDB Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-table-import.html" title="17.6.1.3 Importing InnoDB Tables">
Section 17.6.1.3, “Importing InnoDB Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-acid.html" title="17.2 InnoDB and the ACID Model">
Section 17.2, “InnoDB and the ACID Model”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-row-format.html" title="17.10 InnoDB Row Formats">
Section 17.10, “InnoDB Row Formats”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="glossary.html" title="MySQL Glossary">
MySQL Glossary
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="optimize-table.html" title="15.7.3.4 OPTIMIZE TABLE Statement">
Section 15.7.3.4, “OPTIMIZE TABLE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-truncate-table-reclaim-space.html" title="17.11.5 Reclaiming Disk Space with TRUNCATE TABLE">
Section 17.11.5, “Reclaiming Disk Space with TRUNCATE TABLE”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-solutions-partitioning.html" title="19.4.6 Replicating Different Databases to Different Replicas">
Section 19.4.6, “Replicating Different Databases to Different Replicas”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="partitioning-limitations.html" title="26.6 Restrictions and Limitations on Partitioning">
Section 26.6, “Restrictions and Limitations on Partitioning”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-compression-syntax-warnings.html" title="17.9.1.7 SQL Compression Syntax Warnings and Errors">
Section 17.9.1.7, “SQL Compression Syntax Warnings and Errors”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-troubleshooting-datadict.html" title="17.20.4 Troubleshooting InnoDB Data Dictionary Operations">
Section 17.20.4, “Troubleshooting InnoDB Data Dictionary Operations”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_fill_factor
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="sorted-index-builds.html" title="17.6.2.3 Sorted Index Builds">
Section 17.6.2.3, “Sorted Index Builds”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-physical-structure.html" title="17.6.2.2 The Physical Structure of an InnoDB Index">
Section 17.6.2.2, “The Physical Structure of an InnoDB Index”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_flush_log_at_timeout
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-redo-log-buffer.html" title="17.5.4 Log Buffer">
Section 17.5.4, “Log Buffer”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_flush_log_at_trx_commit
</h3>
<dl>
<dt>
<a class="xref" href="atomic-ddl.html" title="15.1.1 Atomic Data Definition Statement Support">
Section 15.1.1, “Atomic Data Definition Statement Support”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-binary-log.html" title="19.1.6.4 Binary Logging Options and Variables">
Section 19.1.6.4, “Binary Logging Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-solutions-unexpected-replica-halt.html" title="19.4.2 Handling an Unexpected Halt of a Replica">
Section 19.4.2, “Handling an Unexpected Halt of a Replica”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-acid.html" title="17.2 InnoDB and the ACID Model">
Section 17.2, “InnoDB and the ACID Model”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-redo-log-buffer.html" title="17.5.4 Log Buffer">
Section 17.5.4, “Log Buffer”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="optimizing-innodb-transaction-management.html" title="10.5.2 Optimizing InnoDB Transaction Management">
Section 10.5.2, “Optimizing InnoDB Transaction Management”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-shutdowns.html" title="19.5.1.28 Replication and Source or Replica Shutdowns">
Section 19.5.1.28, “Replication and Source or Replica Shutdowns”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_flush_method
</h3>
<dl>
<dt>
<a class="xref" href="innodb-doublewrite-buffer.html" title="17.6.4 Doublewrite Buffer">
Section 17.6.4, “Doublewrite Buffer”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-dedicated-server.html" title="17.8.12 Enabling Automatic InnoDB Configuration for a Dedicated MySQL Server">
Section 17.8.12, “Enabling Automatic InnoDB Configuration for a Dedicated MySQL Server”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-file-per-table-tablespaces.html" title="17.6.3.2 File-Per-Table Tablespaces">
Section 17.6.3.2, “File-Per-Table Tablespaces”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="optimizing-innodb-diskio.html" title="10.5.8 Optimizing InnoDB Disk I/O">
Section 10.5.8, “Optimizing InnoDB Disk I/O”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-status-variables.html" title="7.1.10 Server Status Variables">
Section 7.1.10, “Server Status Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_flush_neighbors
</h3>
<dl>
<dt>
<a class="xref" href="innodb-buffer-pool-flushing.html" title="17.8.3.5 Configuring Buffer Pool Flushing">
Section 17.8.3.5, “Configuring Buffer Pool Flushing”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="glossary.html" title="MySQL Glossary">
MySQL Glossary
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="optimizing-innodb-diskio.html" title="10.5.8 Optimizing InnoDB Disk I/O">
Section 10.5.8, “Optimizing InnoDB Disk I/O”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_flush_sync
</h3>
<dl>
<dt>
<a class="xref" href="innodb-configuring-io-capacity.html" title="17.8.7 Configuring InnoDB I/O Capacity">
Section 17.8.7, “Configuring InnoDB I/O Capacity”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_flushing_avg_loops
</h3>
<dl>
<dt>
<a class="xref" href="innodb-buffer-pool-flushing.html" title="17.8.3.5 Configuring Buffer Pool Flushing">
Section 17.8.3.5, “Configuring Buffer Pool Flushing”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_force_load_corrupted
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_force_recovery
</h3>
<dl>
<dt>
<a class="xref" href="drop-table.html" title="15.1.32 DROP TABLE Statement">
Section 15.1.32, “DROP TABLE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="forcing-innodb-recovery.html" title="17.20.3 Forcing InnoDB Recovery">
Section 17.20.3, “Forcing InnoDB Recovery”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="bug-reports.html" title="1.6 How to Report Bugs or Problems">
Section 1.6, “How to Report Bugs or Problems”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-recovery.html" title="17.18.2 InnoDB Recovery">
Section 17.18.2, “InnoDB Recovery”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="optimizing-innodb-transaction-management.html" title="10.5.2 Optimizing InnoDB Transaction Management">
Section 10.5.2, “Optimizing InnoDB Transaction Management”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="rebuilding-tables.html" title="3.14 Rebuilding or Repairing Tables or Indexes">
Section 3.14, “Rebuilding or Repairing Tables or Indexes”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-troubleshooting-recovery.html" title="17.20.2 Troubleshooting Recovery Failures">
Section 17.20.2, “Troubleshooting Recovery Failures”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_fsync_threshold
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="optimizing-innodb-diskio.html" title="10.5.8 Optimizing InnoDB Disk I/O">
Section 10.5.8, “Optimizing InnoDB Disk I/O”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_ft_aux_table
</h3>
<dl>
<dt>
<a class="xref" href="innodb-information-schema-fulltext_index-tables.html" title="17.15.4 InnoDB INFORMATION_SCHEMA FULLTEXT Index Tables">
Section 17.15.4, “InnoDB INFORMATION_SCHEMA FULLTEXT Index Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-innodb-ft-being-deleted-table.html" title="28.4.14 The INFORMATION_SCHEMA INNODB_FT_BEING_DELETED Table">
Section 28.4.14, “The INFORMATION_SCHEMA INNODB_FT_BEING_DELETED Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-innodb-ft-config-table.html" title="28.4.15 The INFORMATION_SCHEMA INNODB_FT_CONFIG Table">
Section 28.4.15, “The INFORMATION_SCHEMA INNODB_FT_CONFIG Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-innodb-ft-deleted-table.html" title="28.4.17 The INFORMATION_SCHEMA INNODB_FT_DELETED Table">
Section 28.4.17, “The INFORMATION_SCHEMA INNODB_FT_DELETED Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-innodb-ft-index-cache-table.html" title="28.4.18 The INFORMATION_SCHEMA INNODB_FT_INDEX_CACHE Table">
Section 28.4.18, “The INFORMATION_SCHEMA INNODB_FT_INDEX_CACHE Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-innodb-ft-index-table-table.html" title="28.4.19 The INFORMATION_SCHEMA INNODB_FT_INDEX_TABLE Table">
Section 28.4.19, “The INFORMATION_SCHEMA INNODB_FT_INDEX_TABLE Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_ft_cache_size
</h3>
<dl>
<dt>
<a class="xref" href="innodb-fulltext-index.html" title="17.6.2.4 InnoDB Full-Text Indexes">
Section 17.6.2.4, “InnoDB Full-Text Indexes”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-information-schema-fulltext_index-tables.html" title="17.15.4 InnoDB INFORMATION_SCHEMA FULLTEXT Index Tables">
Section 17.15.4, “InnoDB INFORMATION_SCHEMA FULLTEXT Index Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="glossary.html" title="MySQL Glossary">
MySQL Glossary
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-innodb-ft-index-cache-table.html" title="28.4.18 The INFORMATION_SCHEMA INNODB_FT_INDEX_CACHE Table">
Section 28.4.18, “The INFORMATION_SCHEMA INNODB_FT_INDEX_CACHE Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_ft_enable_diag_print
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_ft_enable_stopword
</h3>
<dl>
<dt>
<a class="xref" href="fulltext-boolean.html" title="14.9.2 Boolean Full-Text Searches">
Section 14.9.2, “Boolean Full-Text Searches”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="fulltext-fine-tuning.html" title="14.9.6 Fine-Tuning MySQL Full-Text Search">
Section 14.9.6, “Fine-Tuning MySQL Full-Text Search”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="fulltext-natural-language.html" title="14.9.1 Natural Language Full-Text Searches">
Section 14.9.1, “Natural Language Full-Text Searches”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_ft_max_token_size
</h3>
<dl>
<dt>
<a class="xref" href="fulltext-boolean.html" title="14.9.2 Boolean Full-Text Searches">
Section 14.9.2, “Boolean Full-Text Searches”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="fulltext-fine-tuning.html" title="14.9.6 Fine-Tuning MySQL Full-Text Search">
Section 14.9.6, “Fine-Tuning MySQL Full-Text Search”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="fulltext-stopwords.html" title="14.9.4 Full-Text Stopwords">
Section 14.9.4, “Full-Text Stopwords”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="fulltext-search-ngram.html" title="14.9.8 ngram Full-Text Parser">
Section 14.9.8, “ngram Full-Text Parser”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_ft_min_token_size
</h3>
<dl>
<dt>
<a class="xref" href="fulltext-boolean.html" title="14.9.2 Boolean Full-Text Searches">
Section 14.9.2, “Boolean Full-Text Searches”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="fulltext-fine-tuning.html" title="14.9.6 Fine-Tuning MySQL Full-Text Search">
Section 14.9.6, “Fine-Tuning MySQL Full-Text Search”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="fulltext-stopwords.html" title="14.9.4 Full-Text Stopwords">
Section 14.9.4, “Full-Text Stopwords”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="fulltext-search-mecab.html" title="14.9.9 MeCab Full-Text Parser Plugin">
Section 14.9.9, “MeCab Full-Text Parser Plugin”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="fulltext-natural-language.html" title="14.9.1 Natural Language Full-Text Searches">
Section 14.9.1, “Natural Language Full-Text Searches”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="fulltext-search-ngram.html" title="14.9.8 ngram Full-Text Parser">
Section 14.9.8, “ngram Full-Text Parser”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_ft_num_word_optimize
</h3>
<dl>
<dt>
<a class="xref" href="fulltext-fine-tuning.html" title="14.9.6 Fine-Tuning MySQL Full-Text Search">
Section 14.9.6, “Fine-Tuning MySQL Full-Text Search”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="optimize-table.html" title="15.7.3.4 OPTIMIZE TABLE Statement">
Section 15.7.3.4, “OPTIMIZE TABLE Statement”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_ft_result_cache_limit
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_ft_server_stopword_table
</h3>
<dl>
<dt>
<a class="xref" href="fulltext-boolean.html" title="14.9.2 Boolean Full-Text Searches">
Section 14.9.2, “Boolean Full-Text Searches”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="fulltext-fine-tuning.html" title="14.9.6 Fine-Tuning MySQL Full-Text Search">
Section 14.9.6, “Fine-Tuning MySQL Full-Text Search”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="fulltext-stopwords.html" title="14.9.4 Full-Text Stopwords">
Section 14.9.4, “Full-Text Stopwords”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="fulltext-natural-language.html" title="14.9.1 Natural Language Full-Text Searches">
Section 14.9.1, “Natural Language Full-Text Searches”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-innodb-ft-default-stopword-table.html" title="28.4.16 The INFORMATION_SCHEMA INNODB_FT_DEFAULT_STOPWORD Table">
Section 28.4.16, “The INFORMATION_SCHEMA INNODB_FT_DEFAULT_STOPWORD Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_ft_sort_pll_degree
</h3>
<dl>
<dt>
<a class="xref" href="innodb-fulltext-index.html" title="17.6.2.4 InnoDB Full-Text Indexes">
Section 17.6.2.4, “InnoDB Full-Text Indexes”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_ft_total_cache_size
</h3>
<dl>
<dt>
<a class="xref" href="innodb-fulltext-index.html" title="17.6.2.4 InnoDB Full-Text Indexes">
Section 17.6.2.4, “InnoDB Full-Text Indexes”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-information-schema-fulltext_index-tables.html" title="17.15.4 InnoDB INFORMATION_SCHEMA FULLTEXT Index Tables">
Section 17.15.4, “InnoDB INFORMATION_SCHEMA FULLTEXT Index Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-innodb-ft-index-cache-table.html" title="28.4.18 The INFORMATION_SCHEMA INNODB_FT_INDEX_CACHE Table">
Section 28.4.18, “The INFORMATION_SCHEMA INNODB_FT_INDEX_CACHE Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_ft_user_stopword_table
</h3>
<dl>
<dt>
<a class="xref" href="fulltext-boolean.html" title="14.9.2 Boolean Full-Text Searches">
Section 14.9.2, “Boolean Full-Text Searches”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="fulltext-fine-tuning.html" title="14.9.6 Fine-Tuning MySQL Full-Text Search">
Section 14.9.6, “Fine-Tuning MySQL Full-Text Search”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="fulltext-stopwords.html" title="14.9.4 Full-Text Stopwords">
Section 14.9.4, “Full-Text Stopwords”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="fulltext-natural-language.html" title="14.9.1 Natural Language Full-Text Searches">
Section 14.9.1, “Natural Language Full-Text Searches”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-innodb-ft-default-stopword-table.html" title="28.4.16 The INFORMATION_SCHEMA INNODB_FT_DEFAULT_STOPWORD Table">
Section 28.4.16, “The INFORMATION_SCHEMA INNODB_FT_DEFAULT_STOPWORD Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_idle_flush_pct
</h3>
<dl>
<dt>
<a class="xref" href="innodb-buffer-pool-flushing.html" title="17.8.3.5 Configuring Buffer Pool Flushing">
Section 17.8.3.5, “Configuring Buffer Pool Flushing”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="optimizing-innodb-diskio.html" title="10.5.8 Optimizing InnoDB Disk I/O">
Section 10.5.8, “Optimizing InnoDB Disk I/O”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_io_capacity
</h3>
<dl>
<dt>
<a class="xref" href="innodb-buffer-pool-flushing.html" title="17.8.3.5 Configuring Buffer Pool Flushing">
Section 17.8.3.5, “Configuring Buffer Pool Flushing”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-configuring-io-capacity.html" title="17.8.7 Configuring InnoDB I/O Capacity">
Section 17.8.7, “Configuring InnoDB I/O Capacity”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="faqs-innodb-change-buffer.html" title="A.16 MySQL 8.4 FAQ: InnoDB Change Buffer">
Section A.16, “MySQL 8.4 FAQ: InnoDB Change Buffer”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="optimizing-innodb-diskio.html" title="10.5.8 Optimizing InnoDB Disk I/O">
Section 10.5.8, “Optimizing InnoDB Disk I/O”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_io_capacity_max
</h3>
<dl>
<dt>
<a class="xref" href="innodb-buffer-pool-flushing.html" title="17.8.3.5 Configuring Buffer Pool Flushing">
Section 17.8.3.5, “Configuring Buffer Pool Flushing”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-configuring-io-capacity.html" title="17.8.7 Configuring InnoDB I/O Capacity">
Section 17.8.7, “Configuring InnoDB I/O Capacity”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="optimizing-innodb-diskio.html" title="10.5.8 Optimizing InnoDB Disk I/O">
Section 10.5.8, “Optimizing InnoDB Disk I/O”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_limit_optimistic_insert_debug
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_lock_wait_timeout
</h3>
<dl>
<dt>
<a class="xref" href="converting-tables-to-innodb.html" title="17.6.1.5 Converting Tables from MyISAM to InnoDB">
Section 17.6.1.5, “Converting Tables from MyISAM to InnoDB”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-deadlock-detection.html" title="17.7.5.2 Deadlock Detection">
Section 17.7.5.2, “Deadlock Detection”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-deadlocks.html" title="17.7.5 Deadlocks in InnoDB">
Section 17.7.5, “Deadlocks in InnoDB”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="internal-locking.html" title="10.11.1 Internal Locking Methods">
Section 10.11.1, “Internal Locking Methods”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="glossary.html" title="MySQL Glossary">
MySQL Glossary
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-timeout.html" title="19.5.1.32 Replication Retries and Timeouts">
Section 19.5.1.32, “Replication Retries and Timeouts”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_log_buffer_size
</h3>
<dl>
<dt>
<a class="xref" href="innodb-init-startup-configuration.html" title="17.8.1 InnoDB Startup Configuration">
Section 17.8.1, “InnoDB Startup Configuration”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-redo-log-buffer.html" title="17.5.4 Log Buffer">
Section 17.5.4, “Log Buffer”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="glossary.html" title="MySQL Glossary">
MySQL Glossary
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="optimizing-innodb-logging.html" title="10.5.4 Optimizing InnoDB Redo Logging">
Section 10.5.4, “Optimizing InnoDB Redo Logging”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_log_checkpoint_fuzzy_now
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_log_checkpoint_now
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_log_checksums
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_log_compressed_pages
</h3>
<dl>
<dt>
<a class="xref" href="innodb-performance-compression-oltp.html" title="17.9.1.6 Compression for OLTP Workloads">
Section 17.9.1.6, “Compression for OLTP Workloads”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="optimizing-innodb-diskio.html" title="10.5.8 Optimizing InnoDB Disk I/O">
Section 10.5.8, “Optimizing InnoDB Disk I/O”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_log_file_size
</h3>
<dl>
<dt>
<a class="xref" href="innodb-buffer-pool-flushing.html" title="17.8.3.5 Configuring Buffer Pool Flushing">
Section 17.8.3.5, “Configuring Buffer Pool Flushing”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-read-only-instance.html" title="17.8.2 Configuring InnoDB for Read-Only Operation">
Section 17.8.2, “Configuring InnoDB for Read-Only Operation”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-dedicated-server.html" title="17.8.12 Enabling Automatic InnoDB Configuration for a Dedicated MySQL Server">
Section 17.8.12, “Enabling Automatic InnoDB Configuration for a Dedicated MySQL Server”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="data-directory-initialization.html" title="2.9.1 Initializing the Data Directory">
Section 2.9.1, “Initializing the Data Directory”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-init-startup-configuration.html" title="17.8.1 InnoDB Startup Configuration">
Section 17.8.1, “InnoDB Startup Configuration”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="optimizing-innodb-diskio.html" title="10.5.8 Optimizing InnoDB Disk I/O">
Section 10.5.8, “Optimizing InnoDB Disk I/O”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_log_files_in_group
</h3>
<dl>
<dt>
<a class="xref" href="innodb-dedicated-server.html" title="17.8.12 Enabling Automatic InnoDB Configuration for a Dedicated MySQL Server">
Section 17.8.12, “Enabling Automatic InnoDB Configuration for a Dedicated MySQL Server”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-init-startup-configuration.html" title="17.8.1 InnoDB Startup Configuration">
Section 17.8.1, “InnoDB Startup Configuration”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_log_group_home_dir
</h3>
<dl>
<dt>
<a class="xref" href="clone-plugin-remote.html" title="7.6.7.3 Cloning Remote Data">
Section 7.6.7.3, “Cloning Remote Data”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="data-directory-initialization.html" title="2.9.1 Initializing the Data Directory">
Section 2.9.1, “Initializing the Data Directory”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-init-startup-configuration.html" title="17.8.1 InnoDB Startup Configuration">
Section 17.8.1, “InnoDB Startup Configuration”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-redo-log.html" title="17.6.5 Redo Log">
Section 17.6.5, “Redo Log”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-undo-tablespaces.html" title="17.6.3.4 Undo Tablespaces">
Section 17.6.3.4, “Undo Tablespaces”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-enterprise-backup.html" title="20.5.6 Using MySQL Enterprise Backup with Group Replication">
Section 20.5.6, “Using MySQL Enterprise Backup with Group Replication”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_log_spin_cpu_abs_lwm
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="optimizing-innodb-logging.html" title="10.5.4 Optimizing InnoDB Redo Logging">
Section 10.5.4, “Optimizing InnoDB Redo Logging”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_log_spin_cpu_pct_hwm
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="optimizing-innodb-logging.html" title="10.5.4 Optimizing InnoDB Redo Logging">
Section 10.5.4, “Optimizing InnoDB Redo Logging”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_log_wait_for_flush_spin_hwm
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="optimizing-innodb-logging.html" title="10.5.4 Optimizing InnoDB Redo Logging">
Section 10.5.4, “Optimizing InnoDB Redo Logging”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_log_write_ahead_size
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="optimizing-innodb-logging.html" title="10.5.4 Optimizing InnoDB Redo Logging">
Section 10.5.4, “Optimizing InnoDB Redo Logging”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_log_writer_threads
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="optimizing-innodb-logging.html" title="10.5.4 Optimizing InnoDB Redo Logging">
Section 10.5.4, “Optimizing InnoDB Redo Logging”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_lru_scan_depth
</h3>
<dl>
<dt>
<a class="xref" href="innodb-buffer-pool-flushing.html" title="17.8.3.5 Configuring Buffer Pool Flushing">
Section 17.8.3.5, “Configuring Buffer Pool Flushing”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_max_dirty_pages_pct
</h3>
<dl>
<dt>
<a class="xref" href="innodb-buffer-pool-flushing.html" title="17.8.3.5 Configuring Buffer Pool Flushing">
Section 17.8.3.5, “Configuring Buffer Pool Flushing”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="optimizing-innodb-diskio.html" title="10.5.8 Optimizing InnoDB Disk I/O">
Section 10.5.8, “Optimizing InnoDB Disk I/O”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_max_dirty_pages_pct_lwm
</h3>
<dl>
<dt>
<a class="xref" href="innodb-buffer-pool-flushing.html" title="17.8.3.5 Configuring Buffer Pool Flushing">
Section 17.8.3.5, “Configuring Buffer Pool Flushing”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_max_purge_lag
</h3>
<dl>
<dt>
<a class="xref" href="innodb-multi-versioning.html" title="17.3 InnoDB Multi-Versioning">
Section 17.3, “InnoDB Multi-Versioning”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="glossary.html" title="MySQL Glossary">
MySQL Glossary
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-purge-configuration.html" title="17.8.9 Purge Configuration">
Section 17.8.9, “Purge Configuration”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_max_purge_lag_delay
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-purge-configuration.html" title="17.8.9 Purge Configuration">
Section 17.8.9, “Purge Configuration”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_max_undo_log_size
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-undo-tablespaces.html" title="17.6.3.4 Undo Tablespaces">
Section 17.6.3.4, “Undo Tablespaces”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_merge_threshold_set_all_debug
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_monitor_disable
</h3>
<dl>
<dt>
<a class="xref" href="innodb-information-schema-metrics-table.html" title="17.15.6 InnoDB INFORMATION_SCHEMA Metrics Table">
Section 17.15.6, “InnoDB INFORMATION_SCHEMA Metrics Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="show-engine.html" title="15.7.7.16 SHOW ENGINE Statement">
Section 15.7.7.16, “SHOW ENGINE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-innodb-metrics-table.html" title="28.4.21 The INFORMATION_SCHEMA INNODB_METRICS Table">
Section 28.4.21, “The INFORMATION_SCHEMA INNODB_METRICS Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_monitor_enable
</h3>
<dl>
<dt>
<a class="xref" href="innodb-information-schema-metrics-table.html" title="17.15.6 InnoDB INFORMATION_SCHEMA Metrics Table">
Section 17.15.6, “InnoDB INFORMATION_SCHEMA Metrics Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="show-engine.html" title="15.7.7.16 SHOW ENGINE Statement">
Section 15.7.7.16, “SHOW ENGINE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-innodb-metrics-table.html" title="28.4.21 The INFORMATION_SCHEMA INNODB_METRICS Table">
Section 28.4.21, “The INFORMATION_SCHEMA INNODB_METRICS Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_monitor_reset
</h3>
<dl>
<dt>
<a class="xref" href="innodb-information-schema-metrics-table.html" title="17.15.6 InnoDB INFORMATION_SCHEMA Metrics Table">
Section 17.15.6, “InnoDB INFORMATION_SCHEMA Metrics Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-innodb-metrics-table.html" title="28.4.21 The INFORMATION_SCHEMA INNODB_METRICS Table">
Section 28.4.21, “The INFORMATION_SCHEMA INNODB_METRICS Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_monitor_reset_all
</h3>
<dl>
<dt>
<a class="xref" href="innodb-information-schema-metrics-table.html" title="17.15.6 InnoDB INFORMATION_SCHEMA Metrics Table">
Section 17.15.6, “InnoDB INFORMATION_SCHEMA Metrics Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-innodb-metrics-table.html" title="28.4.21 The INFORMATION_SCHEMA INNODB_METRICS Table">
Section 28.4.21, “The INFORMATION_SCHEMA INNODB_METRICS Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_numa_interleave
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_old_blocks_pct
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-performance-midpoint_insertion.html" title="17.8.3.3 Making the Buffer Pool Scan Resistant">
Section 17.8.3.3, “Making the Buffer Pool Scan Resistant”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="glossary.html" title="MySQL Glossary">
MySQL Glossary
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_old_blocks_time
</h3>
<dl>
<dt>
<a class="xref" href="innodb-buffer-pool.html" title="17.5.1 Buffer Pool">
Section 17.5.1, “Buffer Pool”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-performance-midpoint_insertion.html" title="17.8.3.3 Making the Buffer Pool Scan Resistant">
Section 17.8.3.3, “Making the Buffer Pool Scan Resistant”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_online_alter_log_max_size
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="glossary.html" title="MySQL Glossary">
MySQL Glossary
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-online-ddl-failure-conditions.html" title="17.12.7 Online DDL Failure Conditions">
Section 17.12.7, “Online DDL Failure Conditions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-online-ddl-space-requirements.html" title="17.12.3 Online DDL Space Requirements">
Section 17.12.3, “Online DDL Space Requirements”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_open_files
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_optimize_fulltext_only
</h3>
<dl>
<dt>
<a class="xref" href="fulltext-fine-tuning.html" title="14.9.6 Fine-Tuning MySQL Full-Text Search">
Section 14.9.6, “Fine-Tuning MySQL Full-Text Search”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-fulltext-index.html" title="17.6.2.4 InnoDB Full-Text Indexes">
Section 17.6.2.4, “InnoDB Full-Text Indexes”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-information-schema-fulltext_index-tables.html" title="17.15.4 InnoDB INFORMATION_SCHEMA FULLTEXT Index Tables">
Section 17.15.4, “InnoDB INFORMATION_SCHEMA FULLTEXT Index Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="optimize-table.html" title="15.7.3.4 OPTIMIZE TABLE Statement">
Section 15.7.3.4, “OPTIMIZE TABLE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-innodb-ft-index-table-table.html" title="28.4.19 The INFORMATION_SCHEMA INNODB_FT_INDEX_TABLE Table">
Section 28.4.19, “The INFORMATION_SCHEMA INNODB_FT_INDEX_TABLE Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_page_cleaners
</h3>
<dl>
<dt>
<a class="xref" href="innodb-buffer-pool-flushing.html" title="17.8.3.5 Configuring Buffer Pool Flushing">
Section 17.8.3.5, “Configuring Buffer Pool Flushing”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="glossary.html" title="MySQL Glossary">
MySQL Glossary
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_page_size
</h3>
<dl>
<dt>
<a class="xref" href="clone-plugin-remote.html" title="7.6.7.3 Cloning Remote Data">
Section 7.6.7.3, “Cloning Remote Data”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="converting-tables-to-innodb.html" title="17.6.1.5 Converting Tables from MyISAM to InnoDB">
Section 17.6.1.5, “Converting Tables from MyISAM to InnoDB”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="create-table.html" title="15.1.20 CREATE TABLE Statement">
Section 15.1.20, “CREATE TABLE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="create-tablespace.html" title="15.1.21 CREATE TABLESPACE Statement">
Section 15.1.21, “CREATE TABLESPACE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-compression-usage.html" title="17.9.1.2 Creating Compressed Tables">
Section 17.9.1.2, “Creating Compressed Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-analyze-table-complexity.html" title="17.8.10.3 Estimating ANALYZE TABLE Complexity for InnoDB Tables">
Section 17.8.10.3, “Estimating ANALYZE TABLE Complexity for InnoDB Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-buffer-pool-in-core-file.html" title="17.8.3.7 Excluding or Including Buffer Pool Pages from Core Files">
Section 17.8.3.7, “Excluding or Including Buffer Pool Pages from Core Files”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-file-space.html" title="17.11.2 File Space Management">
Section 17.11.2, “File Space Management”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="general-tablespaces.html" title="17.6.3.3 General Tablespaces">
Section 17.6.3.3, “General Tablespaces”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-compression-internals.html" title="17.9.1.5 How Compression Works for InnoDB Tables">
Section 17.9.1.5, “How Compression Works for InnoDB Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-table-import.html" title="17.6.1.3 Importing InnoDB Tables">
Section 17.6.1.3, “Importing InnoDB Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-limits.html" title="17.21 InnoDB Limits">
Section 17.21, “InnoDB Limits”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-page-compression.html" title="17.9.2 InnoDB Page Compression">
Section 17.9.2, “InnoDB Page Compression”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-restrictions-limitations.html" title="17.22 InnoDB Restrictions and Limitations">
Section 17.22, “InnoDB Restrictions and Limitations”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-init-startup-configuration.html" title="17.8.1 InnoDB Startup Configuration">
Section 17.8.1, “InnoDB Startup Configuration”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="column-count-limit.html" title="10.4.7 Limits on Table Column Count and Row Size">
Section 10.4.7, “Limits on Table Column Count and Row Size”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="glossary.html" title="MySQL Glossary">
MySQL Glossary
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="optimizing-innodb-diskio.html" title="10.5.8 Optimizing InnoDB Disk I/O">
Section 10.5.8, “Optimizing InnoDB Disk I/O”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="optimizing-innodb-logging.html" title="10.5.4 Optimizing InnoDB Redo Logging">
Section 10.5.4, “Optimizing InnoDB Redo Logging”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-compression-background.html" title="17.9.1.1 Overview of Table Compression">
Section 17.9.1.1, “Overview of Table Compression”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-tablespace-autoextend-size.html" title="17.6.3.9 Tablespace AUTOEXTEND_SIZE Configuration">
Section 17.6.3.9, “Tablespace AUTOEXTEND_SIZE Configuration”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-files-table.html" title="28.3.15 The INFORMATION_SCHEMA FILES Table">
Section 28.3.15, “The INFORMATION_SCHEMA FILES Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-physical-structure.html" title="17.6.2.2 The Physical Structure of an InnoDB Index">
Section 17.6.2.2, “The Physical Structure of an InnoDB Index”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_parallel_read_threads
</h3>
<dl>
<dt>
<a class="xref" href="check-table.html" title="15.7.3.2 CHECK TABLE Statement">
Section 15.7.3.2, “CHECK TABLE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="online-ddl-parallel-thread-configuration.html" title="17.12.5 Configuring Parallel Threads for Online DDL Operations">
Section 17.12.5, “Configuring Parallel Threads for Online DDL Operations”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_print_all_deadlocks
</h3>
<dl>
<dt>
<a class="xref" href="innodb-deadlock-example.html" title="17.7.5.1 An InnoDB Deadlock Example">
Section 17.7.5.1, “An InnoDB Deadlock Example”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="converting-tables-to-innodb.html" title="17.6.1.5 Converting Tables from MyISAM to InnoDB">
Section 17.6.1.5, “Converting Tables from MyISAM to InnoDB”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-deadlocks.html" title="17.7.5 Deadlocks in InnoDB">
Section 17.7.5, “Deadlocks in InnoDB”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-deadlocks-handling.html" title="17.7.5.3 How to Minimize and Handle Deadlocks">
Section 17.7.5.3, “How to Minimize and Handle Deadlocks”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-troubleshooting.html" title="17.20 InnoDB Troubleshooting">
Section 17.20, “InnoDB Troubleshooting”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_print_ddl_logs
</h3>
<dl>
<dt>
<a class="xref" href="atomic-ddl.html" title="15.1.1 Atomic Data Definition Statement Support">
Section 15.1.1, “Atomic Data Definition Statement Support”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_purge_batch_size
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-purge-configuration.html" title="17.8.9 Purge Configuration">
Section 17.8.9, “Purge Configuration”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_purge_rseg_truncate_frequency
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-purge-configuration.html" title="17.8.9 Purge Configuration">
Section 17.8.9, “Purge Configuration”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-undo-tablespaces.html" title="17.6.3.4 Undo Tablespaces">
Section 17.6.3.4, “Undo Tablespaces”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_purge_threads
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="glossary.html" title="MySQL Glossary">
MySQL Glossary
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-purge-configuration.html" title="17.8.9 Purge Configuration">
Section 17.8.9, “Purge Configuration”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_random_read_ahead
</h3>
<dl>
<dt>
<a class="xref" href="innodb-performance-read_ahead.html" title="17.8.3.4 Configuring InnoDB Buffer Pool Prefetching (Read-Ahead)">
Section 17.8.3.4, “Configuring InnoDB Buffer Pool Prefetching (Read-Ahead)”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="glossary.html" title="MySQL Glossary">
MySQL Glossary
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_read_ahead_threshold
</h3>
<dl>
<dt>
<a class="xref" href="innodb-performance-read_ahead.html" title="17.8.3.4 Configuring InnoDB Buffer Pool Prefetching (Read-Ahead)">
Section 17.8.3.4, “Configuring InnoDB Buffer Pool Prefetching (Read-Ahead)”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_read_io_threads
</h3>
<dl>
<dt>
<a class="xref" href="innodb-performance-multiple_io_threads.html" title="17.8.5 Configuring the Number of Background InnoDB I/O Threads">
Section 17.8.5, “Configuring the Number of Background InnoDB I/O Threads”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-standard-monitor.html" title="17.17.3 InnoDB Standard Monitor and Lock Monitor Output">
Section 17.17.3, “InnoDB Standard Monitor and Lock Monitor Output”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-linux-native-aio.html" title="17.8.6 Using Asynchronous I/O on Linux">
Section 17.8.6, “Using Asynchronous I/O on Linux”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_read_only
</h3>
<dl>
<dt>
<a class="xref" href="analyze-table.html" title="15.7.3.1 ANALYZE TABLE Statement">
Section 15.7.3.1, “ANALYZE TABLE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-read-only-instance.html" title="17.8.2 Configuring InnoDB for Read-Only Operation">
Section 17.8.2, “Configuring InnoDB for Read-Only Operation”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="data-dictionary-usage-differences.html" title="16.7 Data Dictionary Usage Differences">
Section 16.7, “Data Dictionary Usage Differences”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-optimization.html" title="10.2.3 Optimizing INFORMATION_SCHEMA Queries">
Section 10.2.3, “Optimizing INFORMATION_SCHEMA Queries”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-statistics-table.html" title="28.3.34 The INFORMATION_SCHEMA STATISTICS Table">
Section 28.3.34, “The INFORMATION_SCHEMA STATISTICS Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-tables-table.html" title="28.3.38 The INFORMATION_SCHEMA TABLES Table">
Section 28.3.38, “The INFORMATION_SCHEMA TABLES Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_redo_log_archive_dirs
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-redo-log.html" title="17.6.5 Redo Log">
Section 17.6.5, “Redo Log”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_redo_log_capacity
</h3>
<dl>
<dt>
<a class="xref" href="innodb-dedicated-server.html" title="17.8.12 Enabling Automatic InnoDB Configuration for a Dedicated MySQL Server">
Section 17.8.12, “Enabling Automatic InnoDB Configuration for a Dedicated MySQL Server”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-init-startup-configuration.html" title="17.8.1 InnoDB Startup Configuration">
Section 17.8.1, “InnoDB Startup Configuration”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="optimizing-innodb-diskio.html" title="10.5.8 Optimizing InnoDB Disk I/O">
Section 10.5.8, “Optimizing InnoDB Disk I/O”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="optimizing-innodb-logging.html" title="10.5.4 Optimizing InnoDB Redo Logging">
Section 10.5.4, “Optimizing InnoDB Redo Logging”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-redo-log.html" title="17.6.5 Redo Log">
Section 17.6.5, “Redo Log”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-status-variables.html" title="7.1.10 Server Status Variables">
Section 7.1.10, “Server Status Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_redo_log_encrypt
</h3>
<dl>
<dt>
<a class="xref" href="clone-plugin-encrypted-data.html" title="7.6.7.5 Cloning Encrypted Data">
Section 7.6.7.5, “Cloning Encrypted Data”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-data-encryption.html" title="17.13 InnoDB Data-at-Rest Encryption">
Section 17.13, “InnoDB Data-at-Rest Encryption”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_replication_delay
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_rollback_on_timeout
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_rollback_segments
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-undo-logs.html" title="17.6.6 Undo Logs">
Section 17.6.6, “Undo Logs”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-undo-tablespaces.html" title="17.6.3.4 Undo Tablespaces">
Section 17.6.3.4, “Undo Tablespaces”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_saved_page_number_debug
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_segment_reserve_factor
</h3>
<dl>
<dt>
<a class="xref" href="innodb-file-space.html" title="17.11.2 File Space Management">
Section 17.11.2, “File Space Management”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_sort_buffer_size
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="glossary.html" title="MySQL Glossary">
MySQL Glossary
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-online-ddl-space-requirements.html" title="17.12.3 Online DDL Space Requirements">
Section 17.12.3, “Online DDL Space Requirements”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_spin_wait_delay
</h3>
<dl>
<dt>
<a class="xref" href="innodb-performance-spin_lock_polling.html" title="17.8.8 Configuring Spin Lock Polling">
Section 17.8.8, “Configuring Spin Lock Polling”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_spin_wait_pause_multiplier
</h3>
<dl>
<dt>
<a class="xref" href="innodb-performance-spin_lock_polling.html" title="17.8.8 Configuring Spin Lock Polling">
Section 17.8.8, “Configuring Spin Lock Polling”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_stats_auto_recalc
</h3>
<dl>
<dt>
<a class="xref" href="innodb-persistent-stats.html#innodb-persistent-stats-auto-recalc" title="17.8.10.1.1 Configuring Automatic Statistics Calculation for Persistent Optimizer Statistics">
Section 17.8.10.1.1, “Configuring Automatic Statistics Calculation for Persistent Optimizer
Statistics”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-performance-optimizer-statistics.html" title="17.8.10 Configuring Optimizer Statistics for InnoDB">
Section 17.8.10, “Configuring Optimizer Statistics for InnoDB”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-persistent-stats.html#innodb-persistent-stats-table-configuration" title="17.8.10.1.2 Configuring Optimizer Statistics Parameters for Individual Tables">
Section 17.8.10.1.2, “Configuring Optimizer Statistics Parameters for Individual Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="create-table.html" title="15.1.20 CREATE TABLE Statement">
Section 15.1.20, “CREATE TABLE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-persistent-stats.html#innodb-persistent-stats-tables-example" title="17.8.10.1.6 InnoDB Persistent Statistics Tables Example">
Section 17.8.10.1.6, “InnoDB Persistent Statistics Tables Example”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_stats_include_delete_marked
</h3>
<dl>
<dt>
<a class="xref" href="innodb-persistent-stats.html#innodb-persistent-stats-delete-marked" title="17.8.10.1.4 Including Delete-marked Records in Persistent Statistics Calculations">
Section 17.8.10.1.4, “Including Delete-marked Records in Persistent Statistics Calculations”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_stats_method
</h3>
<dl>
<dt>
<a class="xref" href="index-statistics.html" title="10.3.8 InnoDB and MyISAM Index Statistics Collection">
Section 10.3.8, “InnoDB and MyISAM Index Statistics Collection”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="glossary.html" title="MySQL Glossary">
MySQL Glossary
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_stats_on_metadata
</h3>
<dl>
<dt>
<a class="xref" href="innodb-statistics-estimation.html" title="17.8.10.2 Configuring Non-Persistent Optimizer Statistics Parameters">
Section 17.8.10.2, “Configuring Non-Persistent Optimizer Statistics Parameters”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_stats_persistent
</h3>
<dl>
<dt>
<a class="xref" href="analyze-table.html" title="15.7.3.1 ANALYZE TABLE Statement">
Section 15.7.3.1, “ANALYZE TABLE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-statistics-estimation.html" title="17.8.10.2 Configuring Non-Persistent Optimizer Statistics Parameters">
Section 17.8.10.2, “Configuring Non-Persistent Optimizer Statistics Parameters”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-performance-optimizer-statistics.html" title="17.8.10 Configuring Optimizer Statistics for InnoDB">
Section 17.8.10, “Configuring Optimizer Statistics for InnoDB”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-persistent-stats.html#innodb-persistent-stats-table-configuration" title="17.8.10.1.2 Configuring Optimizer Statistics Parameters for Individual Tables">
Section 17.8.10.1.2, “Configuring Optimizer Statistics Parameters for Individual Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-persistent-stats.html" title="17.8.10.1 Configuring Persistent Optimizer Statistics Parameters">
Section 17.8.10.1, “Configuring Persistent Optimizer Statistics Parameters”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="create-index.html" title="15.1.15 CREATE INDEX Statement">
Section 15.1.15, “CREATE INDEX Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="create-table.html" title="15.1.20 CREATE TABLE Statement">
Section 15.1.20, “CREATE TABLE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-analyze-table-complexity.html" title="17.8.10.3 Estimating ANALYZE TABLE Complexity for InnoDB Tables">
Section 17.8.10.3, “Estimating ANALYZE TABLE Complexity for InnoDB Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="optimizing-innodb-many-tables.html" title="10.5.10 Optimizing InnoDB for Systems with Many Tables">
Section 10.5.10, “Optimizing InnoDB for Systems with Many Tables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_stats_persistent_sample_pages
</h3>
<dl>
<dt>
<a class="xref" href="analyze-table.html" title="15.7.3.1 ANALYZE TABLE Statement">
Section 15.7.3.1, “ANALYZE TABLE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-persistent-stats.html#innodb-persistent-stats-table-configuration" title="17.8.10.1.2 Configuring Optimizer Statistics Parameters for Individual Tables">
Section 17.8.10.1.2, “Configuring Optimizer Statistics Parameters for Individual Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-persistent-stats.html#innodb-persistent-stats-pages-sampled" title="17.8.10.1.3 Configuring the Number of Sampled Pages for InnoDB Optimizer Statistics">
Section 17.8.10.1.3, “Configuring the Number of Sampled Pages for InnoDB Optimizer Statistics”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-analyze-table-complexity.html" title="17.8.10.3 Estimating ANALYZE TABLE Complexity for InnoDB Tables">
Section 17.8.10.3, “Estimating ANALYZE TABLE Complexity for InnoDB Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_stats_transient_sample_pages
</h3>
<dl>
<dt>
<a class="xref" href="analyze-table.html" title="15.7.3.1 ANALYZE TABLE Statement">
Section 15.7.3.1, “ANALYZE TABLE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-statistics-estimation.html" title="17.8.10.2 Configuring Non-Persistent Optimizer Statistics Parameters">
Section 17.8.10.2, “Configuring Non-Persistent Optimizer Statistics Parameters”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-analyze-table-complexity.html" title="17.8.10.3 Estimating ANALYZE TABLE Complexity for InnoDB Tables">
Section 17.8.10.3, “Estimating ANALYZE TABLE Complexity for InnoDB Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_status_output
</h3>
<dl>
<dt>
<a class="xref" href="innodb-enabling-monitors.html" title="17.17.2 Enabling InnoDB Monitors">
Section 17.17.2, “Enabling InnoDB Monitors”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_status_output_locks
</h3>
<dl>
<dt>
<a class="xref" href="innodb-enabling-monitors.html" title="17.17.2 Enabling InnoDB Monitors">
Section 17.17.2, “Enabling InnoDB Monitors”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_strict_mode
</h3>
<dl>
<dt>
<a class="xref" href="create-table.html" title="15.1.20 CREATE TABLE Statement">
Section 15.1.20, “CREATE TABLE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="create-tablespace.html" title="15.1.21 CREATE TABLESPACE Statement">
Section 15.1.21, “CREATE TABLESPACE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="create-temporary-table.html" title="15.1.20.2 CREATE TEMPORARY TABLE Statement">
Section 15.1.20.2, “CREATE TEMPORARY TABLE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-compression-usage.html" title="17.9.1.2 Creating Compressed Tables">
Section 17.9.1.2, “Creating Compressed Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-compression-internals.html" title="17.9.1.5 How Compression Works for InnoDB Tables">
Section 17.9.1.5, “How Compression Works for InnoDB Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="glossary.html" title="MySQL Glossary">
MySQL Glossary
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="sql-mode.html" title="7.1.11 Server SQL Modes">
Section 7.1.11, “Server SQL Modes”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-compression-syntax-warnings.html" title="17.9.1.7 SQL Compression Syntax Warnings and Errors">
Section 17.9.1.7, “SQL Compression Syntax Warnings and Errors”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_sync_array_size
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_sync_debug
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="source-configuration-options.html" title="2.8.7 MySQL Source-Configuration Options">
Section 2.8.7, “MySQL Source-Configuration Options”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_sync_spin_loops
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_table_locks
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-locks-set.html" title="17.7.3 Locks Set by Different SQL Statements in InnoDB">
Section 17.7.3, “Locks Set by Different SQL Statements in InnoDB”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_temp_data_file_path
</h3>
<dl>
<dt>
<a class="xref" href="innodb-read-only-instance.html" title="17.8.2 Configuring InnoDB for Read-Only Operation">
Section 17.8.2, “Configuring InnoDB for Read-Only Operation”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-init-startup-configuration.html" title="17.8.1 InnoDB Startup Configuration">
Section 17.8.1, “InnoDB Startup Configuration”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="glossary.html" title="MySQL Glossary">
MySQL Glossary
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-temporary-tablespace.html" title="17.6.3.5 Temporary Tablespaces">
Section 17.6.3.5, “Temporary Tablespaces”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-files-table.html" title="28.3.15 The INFORMATION_SCHEMA FILES Table">
Section 28.3.15, “The INFORMATION_SCHEMA FILES Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_temp_tablespaces_dir
</h3>
<dl>
<dt>
<a class="xref" href="innodb-init-startup-configuration.html" title="17.8.1 InnoDB Startup Configuration">
Section 17.8.1, “InnoDB Startup Configuration”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-redo-log.html" title="17.6.5 Redo Log">
Section 17.6.5, “Redo Log”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-temporary-tablespace.html" title="17.6.3.5 Temporary Tablespaces">
Section 17.6.3.5, “Temporary Tablespaces”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_thread_concurrency
</h3>
<dl>
<dt>
<a class="xref" href="innodb-performance-thread_concurrency.html" title="17.8.4 Configuring Thread Concurrency for InnoDB">
Section 17.8.4, “Configuring Thread Concurrency for InnoDB”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-standard-monitor.html" title="17.17.3 InnoDB Standard Monitor and Lock Monitor Output">
Section 17.17.3, “InnoDB Standard Monitor and Lock Monitor Output”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="faqs-thread-pool.html" title="A.15 MySQL 8.4 FAQ: MySQL Enterprise Thread Pool">
Section A.15, “MySQL 8.4 FAQ: MySQL Enterprise Thread Pool”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="optimizing-innodb-configuration-variables.html" title="10.5.9 Optimizing InnoDB Configuration Variables">
Section 10.5.9, “Optimizing InnoDB Configuration Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_thread_sleep_delay
</h3>
<dl>
<dt>
<a class="xref" href="innodb-performance-thread_concurrency.html" title="17.8.4 Configuring Thread Concurrency for InnoDB">
Section 17.8.4, “Configuring Thread Concurrency for InnoDB”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_tmpdir
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-online-ddl-failure-conditions.html" title="17.12.7 Online DDL Failure Conditions">
Section 17.12.7, “Online DDL Failure Conditions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-online-ddl-space-requirements.html" title="17.12.3 Online DDL Space Requirements">
Section 17.12.3, “Online DDL Space Requirements”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-redo-log.html" title="17.6.5 Redo Log">
Section 17.6.5, “Redo Log”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_trx_purge_view_update_only_debug
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_trx_rseg_n_slots_debug
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_undo_directory
</h3>
<dl>
<dt>
<a class="xref" href="clone-plugin-remote.html" title="7.6.7.3 Cloning Remote Data">
Section 7.6.7.3, “Cloning Remote Data”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-read-only-instance.html" title="17.8.2 Configuring InnoDB for Read-Only Operation">
Section 17.8.2, “Configuring InnoDB for Read-Only Operation”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="create-tablespace.html" title="15.1.21 CREATE TABLESPACE Statement">
Section 15.1.21, “CREATE TABLESPACE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-create-table-external.html" title="17.6.1.2 Creating Tables Externally">
Section 17.6.1.2, “Creating Tables Externally”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="general-tablespaces.html" title="17.6.3.3 General Tablespaces">
Section 17.6.3.3, “General Tablespaces”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-recovery.html" title="17.18.2 InnoDB Recovery">
Section 17.18.2, “InnoDB Recovery”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-init-startup-configuration.html" title="17.8.1 InnoDB Startup Configuration">
Section 17.8.1, “InnoDB Startup Configuration”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-moving-data-files-offline.html" title="17.6.3.6 Moving Tablespace Files While the Server is Offline">
Section 17.6.3.6, “Moving Tablespace Files While the Server is Offline”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-redo-log.html" title="17.6.5 Redo Log">
Section 17.6.5, “Redo Log”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-undo-tablespaces.html" title="17.6.3.4 Undo Tablespaces">
Section 17.6.3.4, “Undo Tablespaces”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-enterprise-backup.html" title="20.5.6 Using MySQL Enterprise Backup with Group Replication">
Section 20.5.6, “Using MySQL Enterprise Backup with Group Replication”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_undo_log_encrypt
</h3>
<dl>
<dt>
<a class="xref" href="clone-plugin-encrypted-data.html" title="7.6.7.5 Cloning Encrypted Data">
Section 7.6.7.5, “Cloning Encrypted Data”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-data-encryption.html" title="17.13 InnoDB Data-at-Rest Encryption">
Section 17.13, “InnoDB Data-at-Rest Encryption”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_undo_log_truncate
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-undo-tablespaces.html" title="17.6.3.4 Undo Tablespaces">
Section 17.6.3.4, “Undo Tablespaces”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_undo_tablespaces
</h3>
<dl>
<dt>
<a class="xref" href="innodb-read-only-instance.html" title="17.8.2 Configuring InnoDB for Read-Only Operation">
Section 17.8.2, “Configuring InnoDB for Read-Only Operation”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="glossary.html" title="MySQL Glossary">
MySQL Glossary
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_use_fdatasync
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="optimizing-innodb-diskio.html" title="10.5.8 Optimizing InnoDB Disk I/O">
Section 10.5.8, “Optimizing InnoDB Disk I/O”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-status-variables.html" title="7.1.10 Server Status Variables">
Section 7.1.10, “Server Status Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_use_native_aio
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="glossary.html" title="MySQL Glossary">
MySQL Glossary
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="optimizing-innodb-diskio.html" title="10.5.8 Optimizing InnoDB Disk I/O">
Section 10.5.8, “Optimizing InnoDB Disk I/O”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-linux-native-aio.html" title="17.8.6 Using Asynchronous I/O on Linux">
Section 17.8.6, “Using Asynchronous I/O on Linux”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_validate_tablespace_paths
</h3>
<dl>
<dt>
<a class="xref" href="innodb-disabling-tablespace-path-validation.html" title="17.6.3.7 Disabling Tablespace Path Validation">
Section 17.6.3.7, “Disabling Tablespace Path Validation”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_version
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
innodb_write_io_threads
</h3>
<dl>
<dt>
<a class="xref" href="innodb-performance-multiple_io_threads.html" title="17.8.5 Configuring the Number of Background InnoDB I/O Threads">
Section 17.8.5, “Configuring the Number of Background InnoDB I/O Threads”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-standard-monitor.html" title="17.17.3 InnoDB Standard Monitor and Lock Monitor Output">
Section 17.17.3, “InnoDB Standard Monitor and Lock Monitor Output”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-linux-native-aio.html" title="17.8.6 Using Asynchronous I/O on Linux">
Section 17.8.6, “Using Asynchronous I/O on Linux”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
insert_id
</h3>
<dl>
<dt>
<a class="xref" href="federated-usagenotes.html" title="18.8.3 FEDERATED Storage Engine Notes and Tips">
Section 18.8.3, “FEDERATED Storage Engine Notes and Tips”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
interactive_timeout
</h3>
<dl>
<dt>
<a class="xref" href="communication-errors.html" title="B.3.2.9 Communication Errors and Aborted Connections">
Section B.3.2.9, “Communication Errors and Aborted Connections”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
internal_tmp_disk_storage_engine
</h3>
<dl>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
internal_tmp_mem_storage_engine
</h3>
<dl>
<dt>
<a class="xref" href="internal-temporary-tables.html" title="10.4.4 Internal Temporary Table Use in MySQL">
Section 10.4.4, “Internal Temporary Table Use in MySQL”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<a name="sysvar-index-J">
</a>
<h3 class="title">
J
</h3>
<p>
[
<a class="link" href="dynindex-sysvar.html#sysvar-index-top">
index top
</a>
]
</p>
<dl>
<dt>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
join_buffer_size
</h3>
<dl>
<dt>
<a class="xref" href="bnl-bka-optimization.html" title="10.2.1.12 Block Nested-Loop and Batched Key Access Joins">
Section 10.2.1.12, “Block Nested-Loop and Batched Key Access Joins”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="hash-joins.html" title="10.2.1.4 Hash Join Optimization">
Section 10.2.1.4, “Hash Join Optimization”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<a name="sysvar-index-K">
</a>
<h3 class="title">
K
</h3>
<p>
[
<a class="link" href="dynindex-sysvar.html#sysvar-index-top">
index top
</a>
]
</p>
<dl>
<dt>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
keep_files_on_create
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
key_buffer_size
</h3>
<dl>
<dt>
<a class="xref" href="optimizing-myisam-bulk-data-loading.html" title="10.6.2 Bulk Data Loading for MyISAM Tables">
Section 10.6.2, “Bulk Data Loading for MyISAM Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="converting-tables-to-innodb.html" title="17.6.1.5 Converting Tables from MyISAM to InnoDB">
Section 17.6.1.5, “Converting Tables from MyISAM to InnoDB”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="estimating-performance.html" title="10.8.5 Estimating Query Performance">
Section 10.8.5, “Estimating Query Performance”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="memory-use.html" title="10.12.3.1 How MySQL Uses Memory">
Section 10.12.3.1, “How MySQL Uses Memory”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="myisam-repair.html" title="9.6.3 How to Repair MyISAM Tables">
Section 9.6.3, “How to Repair MyISAM Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-init-startup-configuration.html" title="17.8.1 InnoDB Startup Configuration">
Section 17.8.1, “InnoDB Startup Configuration”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="known-issues.html" title="B.3.7 Known Issues in MySQL">
Section B.3.7, “Known Issues in MySQL”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="multiple-key-caches.html" title="10.10.2.2 Multiple Key Caches">
Section 10.10.2.2, “Multiple Key Caches”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="delete-optimization.html" title="10.2.5.3 Optimizing DELETE Statements">
Section 10.2.5.3, “Optimizing DELETE Statements”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="repair-table-optimization.html" title="10.6.3 Optimizing REPAIR TABLE Statements">
Section 10.6.3, “Optimizing REPAIR TABLE Statements”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="key-cache-restructuring.html" title="10.10.2.6 Restructuring a Key Cache">
Section 10.10.2.6, “Restructuring a Key Cache”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-status-variables.html" title="7.1.10 Server Status Variables">
Section 7.1.10, “Server Status Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="structured-system-variables.html" title="7.1.9.5 Structured System Variables">
Section 7.1.9.5, “Structured System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="myisam-key-cache.html" title="10.10.2 The MyISAM Key Cache">
Section 10.10.2, “The MyISAM Key Cache”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
key_cache_age_threshold
</h3>
<dl>
<dt>
<a class="xref" href="midpoint-insertion.html" title="10.10.2.3 Midpoint Insertion Strategy">
Section 10.10.2.3, “Midpoint Insertion Strategy”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="structured-system-variables.html" title="7.1.9.5 Structured System Variables">
Section 7.1.9.5, “Structured System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
key_cache_block_size
</h3>
<dl>
<dt>
<a class="xref" href="key-cache-block-size.html" title="10.10.2.5 Key Cache Block Size">
Section 10.10.2.5, “Key Cache Block Size”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="key-cache-restructuring.html" title="10.10.2.6 Restructuring a Key Cache">
Section 10.10.2.6, “Restructuring a Key Cache”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="structured-system-variables.html" title="7.1.9.5 Structured System Variables">
Section 7.1.9.5, “Structured System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
key_cache_division_limit
</h3>
<dl>
<dt>
<a class="xref" href="midpoint-insertion.html" title="10.10.2.3 Midpoint Insertion Strategy">
Section 10.10.2.3, “Midpoint Insertion Strategy”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="structured-system-variables.html" title="7.1.9.5 Structured System Variables">
Section 7.1.9.5, “Structured System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
keyring_aws_cmk_id
</h3>
<dl>
<dt>
<a class="xref" href="keyring-system-variables.html" title="8.4.4.16 Keyring System Variables">
Section 8.4.4.16, “Keyring System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="keyring-functions-plugin-specific.html" title="8.4.4.13 Plugin-Specific Keyring Key-Management Functions">
Section 8.4.4.13, “Plugin-Specific Keyring Key-Management Functions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="keyring-aws-plugin.html" title="8.4.4.7 Using the keyring_aws Amazon Web Services Keyring Plugin">
Section 8.4.4.7, “Using the keyring_aws Amazon Web Services Keyring Plugin”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
keyring_aws_conf_file
</h3>
<dl>
<dt>
<a class="xref" href="keyring-system-variables.html" title="8.4.4.16 Keyring System Variables">
Section 8.4.4.16, “Keyring System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="keyring-aws-plugin.html" title="8.4.4.7 Using the keyring_aws Amazon Web Services Keyring Plugin">
Section 8.4.4.7, “Using the keyring_aws Amazon Web Services Keyring Plugin”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
keyring_aws_data_file
</h3>
<dl>
<dt>
<a class="xref" href="keyring-system-variables.html" title="8.4.4.16 Keyring System Variables">
Section 8.4.4.16, “Keyring System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="keyring-functions-plugin-specific.html" title="8.4.4.13 Plugin-Specific Keyring Key-Management Functions">
Section 8.4.4.13, “Plugin-Specific Keyring Key-Management Functions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="keyring-aws-plugin.html" title="8.4.4.7 Using the keyring_aws Amazon Web Services Keyring Plugin">
Section 8.4.4.7, “Using the keyring_aws Amazon Web Services Keyring Plugin”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
keyring_aws_region
</h3>
<dl>
<dt>
<a class="xref" href="keyring-system-variables.html" title="8.4.4.16 Keyring System Variables">
Section 8.4.4.16, “Keyring System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
keyring_hashicorp_auth_path
</h3>
<dl>
<dt>
<a class="xref" href="keyring-system-variables.html" title="8.4.4.16 Keyring System Variables">
Section 8.4.4.16, “Keyring System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="keyring-hashicorp-plugin.html" title="8.4.4.8 Using the HashiCorp Vault Keyring Plugin">
Section 8.4.4.8, “Using the HashiCorp Vault Keyring Plugin”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
keyring_hashicorp_ca_path
</h3>
<dl>
<dt>
<a class="xref" href="keyring-system-variables.html" title="8.4.4.16 Keyring System Variables">
Section 8.4.4.16, “Keyring System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="keyring-hashicorp-plugin.html" title="8.4.4.8 Using the HashiCorp Vault Keyring Plugin">
Section 8.4.4.8, “Using the HashiCorp Vault Keyring Plugin”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
keyring_hashicorp_caching
</h3>
<dl>
<dt>
<a class="xref" href="keyring-system-variables.html" title="8.4.4.16 Keyring System Variables">
Section 8.4.4.16, “Keyring System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="keyring-hashicorp-plugin.html" title="8.4.4.8 Using the HashiCorp Vault Keyring Plugin">
Section 8.4.4.8, “Using the HashiCorp Vault Keyring Plugin”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
keyring_hashicorp_commit_auth_path
</h3>
<dl>
<dt>
<a class="xref" href="keyring-system-variables.html" title="8.4.4.16 Keyring System Variables">
Section 8.4.4.16, “Keyring System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
keyring_hashicorp_commit_ca_path
</h3>
<dl>
<dt>
<a class="xref" href="keyring-system-variables.html" title="8.4.4.16 Keyring System Variables">
Section 8.4.4.16, “Keyring System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
keyring_hashicorp_commit_caching
</h3>
<dl>
<dt>
<a class="xref" href="keyring-system-variables.html" title="8.4.4.16 Keyring System Variables">
Section 8.4.4.16, “Keyring System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
keyring_hashicorp_commit_role_id
</h3>
<dl>
<dt>
<a class="xref" href="keyring-system-variables.html" title="8.4.4.16 Keyring System Variables">
Section 8.4.4.16, “Keyring System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="keyring-hashicorp-plugin.html" title="8.4.4.8 Using the HashiCorp Vault Keyring Plugin">
Section 8.4.4.8, “Using the HashiCorp Vault Keyring Plugin”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
keyring_hashicorp_commit_server_url
</h3>
<dl>
<dt>
<a class="xref" href="keyring-system-variables.html" title="8.4.4.16 Keyring System Variables">
Section 8.4.4.16, “Keyring System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
keyring_hashicorp_commit_store_path
</h3>
<dl>
<dt>
<a class="xref" href="keyring-system-variables.html" title="8.4.4.16 Keyring System Variables">
Section 8.4.4.16, “Keyring System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="keyring-hashicorp-plugin.html" title="8.4.4.8 Using the HashiCorp Vault Keyring Plugin">
Section 8.4.4.8, “Using the HashiCorp Vault Keyring Plugin”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
keyring_hashicorp_role_id
</h3>
<dl>
<dt>
<a class="xref" href="keyring-system-variables.html" title="8.4.4.16 Keyring System Variables">
Section 8.4.4.16, “Keyring System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="keyring-hashicorp-plugin.html" title="8.4.4.8 Using the HashiCorp Vault Keyring Plugin">
Section 8.4.4.8, “Using the HashiCorp Vault Keyring Plugin”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
keyring_hashicorp_secret_id
</h3>
<dl>
<dt>
<a class="xref" href="keyring-system-variables.html" title="8.4.4.16 Keyring System Variables">
Section 8.4.4.16, “Keyring System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="keyring-hashicorp-plugin.html" title="8.4.4.8 Using the HashiCorp Vault Keyring Plugin">
Section 8.4.4.8, “Using the HashiCorp Vault Keyring Plugin”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
keyring_hashicorp_server_url
</h3>
<dl>
<dt>
<a class="xref" href="keyring-system-variables.html" title="8.4.4.16 Keyring System Variables">
Section 8.4.4.16, “Keyring System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="keyring-hashicorp-plugin.html" title="8.4.4.8 Using the HashiCorp Vault Keyring Plugin">
Section 8.4.4.8, “Using the HashiCorp Vault Keyring Plugin”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
keyring_hashicorp_store_path
</h3>
<dl>
<dt>
<a class="xref" href="keyring-system-variables.html" title="8.4.4.16 Keyring System Variables">
Section 8.4.4.16, “Keyring System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="keyring-hashicorp-plugin.html" title="8.4.4.8 Using the HashiCorp Vault Keyring Plugin">
Section 8.4.4.8, “Using the HashiCorp Vault Keyring Plugin”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
keyring_okv_conf_dir
</h3>
<dl>
<dt>
<a class="xref" href="keyring-system-variables.html" title="8.4.4.16 Keyring System Variables">
Section 8.4.4.16, “Keyring System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="keyring-okv-plugin.html" title="8.4.4.6 Using the keyring_okv KMIP Plugin">
Section 8.4.4.6, “Using the keyring_okv KMIP Plugin”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
keyring_operations
</h3>
<dl>
<dt>
<a class="xref" href="keyring-system-variables.html" title="8.4.4.16 Keyring System Variables">
Section 8.4.4.16, “Keyring System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="keyring-key-migration.html" title="8.4.4.11 Migrating Keys Between Keyring Keystores">
Section 8.4.4.11, “Migrating Keys Between Keyring Keystores”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<a name="sysvar-index-L">
</a>
<h3 class="title">
L
</h3>
<p>
[
<a class="link" href="dynindex-sysvar.html#sysvar-index-top">
index top
</a>
]
</p>
<dl>
<dt>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
large_files_support
</h3>
<dl>
<dt>
<a class="xref" href="partitioning-limitations.html" title="26.6 Restrictions and Limitations on Partitioning">
Section 26.6, “Restrictions and Limitations on Partitioning”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
large_page_size
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
large_pages
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
last_insert_id
</h3>
<dl>
<dt>
<a class="xref" href="binary-log-mixed.html" title="7.4.4.3 Mixed Binary Logging Format">
Section 7.4.4.3, “Mixed Binary Logging Format”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-variables.html" title="19.5.1.39 Replication and Variables">
Section 19.5.1.39, “Replication and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
lc_messages
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="error-message-language.html" title="12.12 Setting the Error Message Language">
Section 12.12, “Setting the Error Message Language”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
lc_messages_dir
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="error-message-language.html" title="12.12 Setting the Error Message Language">
Section 12.12, “Setting the Error Message Language”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
lc_time_names
</h3>
<dl>
<dt>
<a class="xref" href="date-and-time-functions.html" title="14.7 Date and Time Functions">
Section 14.7, “Date and Time Functions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log-mixed.html" title="7.4.4.3 Mixed Binary Logging Format">
Section 7.4.4.3, “Mixed Binary Logging Format”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="locale-support.html" title="12.16 MySQL Server Locale Support">
Section 12.16, “MySQL Server Locale Support”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-variables.html" title="19.5.1.39 Replication and Variables">
Section 19.5.1.39, “Replication and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="string-functions.html" title="14.8 String Functions and Operators">
Section 14.8, “String Functions and Operators”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
license
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
local
</h3>
<dl>
<dt>
<a class="xref" href="load-xml.html" title="15.2.10 LOAD XML Statement">
Section 15.2.10, “LOAD XML Statement”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
local_infile
</h3>
<dl>
<dt>
<a class="xref" href="load-data.html" title="15.2.9 LOAD DATA Statement">
Section 15.2.9, “LOAD DATA Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="source-configuration-options.html" title="2.8.7 MySQL Source-Configuration Options">
Section 2.8.7, “MySQL Source-Configuration Options”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="load-data-local-security.html" title="8.1.6 Security Considerations for LOAD DATA LOCAL">
Section 8.1.6, “Security Considerations for LOAD DATA LOCAL”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
lock_order
</h3>
<dl>
<dt>
<a class="xref" href="lock-order-tool.html" title="7.9.3 The LOCK_ORDER Tool">
Section 7.9.3, “The LOCK_ORDER Tool”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
lock_order_debug_loop
</h3>
<dl>
<dt>
<a class="xref" href="lock-order-tool.html" title="7.9.3 The LOCK_ORDER Tool">
Section 7.9.3, “The LOCK_ORDER Tool”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
lock_order_debug_missing_arc
</h3>
<dl>
<dt>
<a class="xref" href="lock-order-tool.html" title="7.9.3 The LOCK_ORDER Tool">
Section 7.9.3, “The LOCK_ORDER Tool”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
lock_order_debug_missing_key
</h3>
<dl>
<dt>
<a class="xref" href="lock-order-tool.html" title="7.9.3 The LOCK_ORDER Tool">
Section 7.9.3, “The LOCK_ORDER Tool”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
lock_order_debug_missing_unlock
</h3>
<dl>
<dt>
<a class="xref" href="lock-order-tool.html" title="7.9.3 The LOCK_ORDER Tool">
Section 7.9.3, “The LOCK_ORDER Tool”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
lock_order_dependencies
</h3>
<dl>
<dt>
<a class="xref" href="lock-order-tool.html" title="7.9.3 The LOCK_ORDER Tool">
Section 7.9.3, “The LOCK_ORDER Tool”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
lock_order_extra_dependencies
</h3>
<dl>
<dt>
<a class="xref" href="lock-order-tool.html" title="7.9.3 The LOCK_ORDER Tool">
Section 7.9.3, “The LOCK_ORDER Tool”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
lock_order_output_directory
</h3>
<dl>
<dt>
<a class="xref" href="lock-order-tool.html" title="7.9.3 The LOCK_ORDER Tool">
Section 7.9.3, “The LOCK_ORDER Tool”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
lock_order_print_txt
</h3>
<dl>
<dt>
<a class="xref" href="lock-order-tool.html" title="7.9.3 The LOCK_ORDER Tool">
Section 7.9.3, “The LOCK_ORDER Tool”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
lock_order_trace_loop
</h3>
<dl>
<dt>
<a class="xref" href="lock-order-tool.html" title="7.9.3 The LOCK_ORDER Tool">
Section 7.9.3, “The LOCK_ORDER Tool”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
lock_order_trace_missing_arc
</h3>
<dl>
<dt>
<a class="xref" href="lock-order-tool.html" title="7.9.3 The LOCK_ORDER Tool">
Section 7.9.3, “The LOCK_ORDER Tool”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
lock_order_trace_missing_key
</h3>
<dl>
<dt>
<a class="xref" href="lock-order-tool.html" title="7.9.3 The LOCK_ORDER Tool">
Section 7.9.3, “The LOCK_ORDER Tool”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
lock_order_trace_missing_unlock
</h3>
<dl>
<dt>
<a class="xref" href="lock-order-tool.html" title="7.9.3 The LOCK_ORDER Tool">
Section 7.9.3, “The LOCK_ORDER Tool”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
lock_wait_timeout
</h3>
<dl>
<dt>
<a class="xref" href="lock-instance-for-backup.html" title="15.3.5 LOCK INSTANCE FOR BACKUP and UNLOCK INSTANCE Statements">
Section 15.3.5, “LOCK INSTANCE FOR BACKUP and UNLOCK INSTANCE Statements”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
locked_in_memory
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
log
</h3>
<dl>
<dt>
<a class="xref" href="innodb-buffer-pool-resize.html" title="17.8.3.1 Configuring InnoDB Buffer Pool Size">
Section 17.8.3.1, “Configuring InnoDB Buffer Pool Size”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-requirements.html" title="20.3.1 Group Replication Requirements">
Section 20.3.1, “Group Replication Requirements”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="channels-startup-options.html" title="19.2.2.3 Startup Options and Replication Channels">
Section 19.2.2.3, “Startup Options and Replication Channels”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
log_bin
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-binary-log.html" title="19.1.6.4 Binary Logging Options and Variables">
Section 19.1.6.4, “Binary Logging Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-bugs.html" title="19.5.5 How to Report Replication Bugs or Problems">
Section 19.5.5, “How to Report Replication Bugs or Problems”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="reset-binary-logs-and-gtids.html" title="15.4.1.2 RESET BINARY LOGS AND GTIDS Statement">
Section 15.4.1.2, “RESET BINARY LOGS AND GTIDS Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log-setting.html" title="7.4.4.2 Setting The Binary Log Format">
Section 7.4.4.2, “Setting The Binary Log Format”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-howto-masterbaseconfig.html" title="19.1.2.1 Setting the Replication Source Configuration">
Section 19.1.2.1, “Setting the Replication Source Configuration”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log.html" title="7.4.4 The Binary Log">
Section 7.4.4, “The Binary Log”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
log_bin_basename
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-binary-log.html" title="19.1.6.4 Binary Logging Options and Variables">
Section 19.1.6.4, “Binary Logging Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log.html" title="7.4.4 The Binary Log">
Section 7.4.4, “The Binary Log”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
log_bin_index
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-binary-log.html" title="19.1.6.4 Binary Logging Options and Variables">
Section 19.1.6.4, “Binary Logging Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
log_bin_trust_function_creators
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-binary-log.html" title="19.1.6.4 Binary Logging Options and Variables">
Section 19.1.6.4, “Binary Logging Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="faqs-stored-procs.html" title="A.4 MySQL 8.4 FAQ: Stored Procedures and Functions">
Section A.4, “MySQL 8.4 FAQ: Stored Procedures and Functions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="stored-programs-logging.html" title="27.7 Stored Program Binary Logging">
Section 27.7, “Stored Program Binary Logging”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
log_error
</h3>
<dl>
<dt>
<a class="xref" href="error-log-destination-configuration.html" title="7.4.2.2 Default Error Log Destination Configuration">
Section 7.4.2.2, “Default Error Log Destination Configuration”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="error-log-components.html" title="7.5.3 Error Log Components">
Section 7.5.3, “Error Log Components”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="error-log-json.html" title="7.4.2.7 Error Logging in JSON Format">
Section 7.4.2.7, “Error Logging in JSON Format”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="macos-installation-launchd.html" title="2.4.3 Installing and Using the MySQL Launch Daemon">
Section 2.4.3, “Installing and Using the MySQL Launch Daemon”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="docker-mysql-more-topics.html" title="2.5.6.2 More Topics on Deploying MySQL Server with Docker">
Section 2.5.6.2, “More Topics on Deploying MySQL Server with Docker”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
log_error_services
</h3>
<dl>
<dt>
<a class="xref" href="error-log-destination-configuration.html" title="7.4.2.2 Default Error Log Destination Configuration">
Section 7.4.2.2, “Default Error Log Destination Configuration”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="error-log-components.html" title="7.5.3 Error Log Components">
Section 7.5.3, “Error Log Components”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="error-log-configuration.html" title="7.4.2.1 Error Log Configuration">
Section 7.4.2.1, “Error Log Configuration”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="error-log-json.html" title="7.4.2.7 Error Logging in JSON Format">
Section 7.4.2.7, “Error Logging in JSON Format”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="error-log-syslog.html" title="7.4.2.8 Error Logging to the System Log">
Section 7.4.2.8, “Error Logging to the System Log”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="error-log-rule-based-filtering.html" title="7.4.2.6 Rule-Based Error Log Filtering (log_filter_dragnet)">
Section 7.4.2.6, “Rule-Based Error Log Filtering (log_filter_dragnet)”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-error-log-table.html" title="29.12.22.2 The error_log Table">
Section 29.12.22.2, “The error_log Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
log_error_suppression_list
</h3>
<dl>
<dt>
<a class="xref" href="error-log-components.html" title="7.5.3 Error Log Components">
Section 7.5.3, “Error Log Components”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="error-log-configuration.html" title="7.4.2.1 Error Log Configuration">
Section 7.4.2.1, “Error Log Configuration”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="error-log-priority-based-filtering.html" title="7.4.2.5 Priority-Based Error Log Filtering (log_filter_internal)">
Section 7.4.2.5, “Priority-Based Error Log Filtering (log_filter_internal)”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="error-log-rule-based-filtering.html" title="7.4.2.6 Rule-Based Error Log Filtering (log_filter_dragnet)">
Section 7.4.2.6, “Rule-Based Error Log Filtering (log_filter_dragnet)”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="error-log-filtering.html" title="7.4.2.4 Types of Error Log Filtering">
Section 7.4.2.4, “Types of Error Log Filtering”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
log_error_verbosity
</h3>
<dl>
<dt>
<a class="xref" href="communication-errors.html" title="B.3.2.9 Communication Errors and Aborted Connections">
Section B.3.2.9, “Communication Errors and Aborted Connections”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="audit-log-logging-configuration.html" title="8.4.5.5 Configuring Audit Logging Characteristics">
Section 8.4.5.5, “Configuring Audit Logging Characteristics”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-disabling-tablespace-path-validation.html" title="17.6.3.7 Disabling Tablespace Path Validation">
Section 17.6.3.7, “Disabling Tablespace Path Validation”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="error-log-components.html" title="7.5.3 Error Log Components">
Section 7.5.3, “Error Log Components”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="error-log-configuration.html" title="7.4.2.1 Error Log Configuration">
Section 7.4.2.1, “Error Log Configuration”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="error-log-format.html" title="7.4.2.9 Error Log Output Format">
Section 7.4.2.9, “Error Log Output Format”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="error-log-syslog.html" title="7.4.2.8 Error Logging to the System Log">
Section 7.4.2.8, “Error Logging to the System Log”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="kerberos-pluggable-authentication.html" title="8.4.1.8 Kerberos Pluggable Authentication">
Section 8.4.1.8, “Kerberos Pluggable Authentication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log-mixed.html" title="7.4.4.3 Mixed Binary Logging Format">
Section 7.4.4.3, “Mixed Binary Logging Format”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="gone-away.html" title="B.3.2.7 MySQL server has gone away">
Section B.3.2.7, “MySQL server has gone away”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-connection-attribute-tables.html" title="29.12.9 Performance Schema Connection Attribute Tables">
Section 29.12.9, “Performance Schema Connection Attribute Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="error-log-priority-based-filtering.html" title="7.4.2.5 Priority-Based Error Log Filtering (log_filter_internal)">
Section 7.4.2.5, “Priority-Based Error Log Filtering (log_filter_internal)”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="error-log-rule-based-filtering.html" title="7.4.2.6 Rule-Based Error Log Filtering (log_filter_dragnet)">
Section 7.4.2.6, “Rule-Based Error Log Filtering (log_filter_dragnet)”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-options.html" title="7.1.7 Server Command Options">
Section 7.1.7, “Server Command Options”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-configuration-validation.html" title="7.1.3 Server Configuration Validation">
Section 7.1.3, “Server Configuration Validation”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="error-log-filtering.html" title="7.4.2.4 Types of Error Log Filtering">
Section 7.4.2.4, “Types of Error Log Filtering”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="firewall-usage.html" title="8.4.7.3 Using MySQL Enterprise Firewall">
Section 8.4.7.3, “Using MySQL Enterprise Firewall”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-what-is-new.html" title="25.2.4 What is New in MySQL NDB Cluster 8.4">
Section 25.2.4, “What is New in MySQL NDB Cluster 8.4”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
log_output
</h3>
<dl>
<dt>
<a class="xref" href="log-destinations.html" title="7.4.1 Selecting General Query Log and Slow Query Log Output Destinations">
Section 7.4.1, “Selecting General Query Log and Slow Query Log Output Destinations”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="query-log.html" title="7.4.3 The General Query Log">
Section 7.4.3, “The General Query Log”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="slow-query-log.html" title="7.4.5 The Slow Query Log">
Section 7.4.5, “The Slow Query Log”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
log_queries_not_using_indexes
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="slow-query-log.html" title="7.4.5 The Slow Query Log">
Section 7.4.5, “The Slow Query Log”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
log_raw
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
log_replica_updates
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-binary-log.html" title="19.1.6.4 Binary Logging Options and Variables">
Section 19.1.6.4, “Binary Logging Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-requirements.html" title="20.3.1 Group Replication Requirements">
Section 20.3.1, “Group Replication Requirements”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-gtids-concepts.html" title="19.1.3.1 GTID Format and Storage">
Section 19.1.3.1, “GTID Format and Storage”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-solutions-performance.html" title="19.4.7 Improving Replication Performance">
Section 19.4.7, “Improving Replication Performance”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-replication-issues.html" title="25.7.3 Known Issues in NDB Cluster Replication">
Section 25.7.3, “Known Issues in NDB Cluster Replication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-program-options-mysqld" title="25.4.3.9.1 MySQL Server Options for NDB Cluster">
Section 25.4.3.9.1, “MySQL Server Options for NDB Cluster”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-replication-multi-source.html" title="25.7.10 NDB Cluster Replication: Bidirectional and Circular Replication">
Section 25.7.10, “NDB Cluster Replication: Bidirectional and Circular Replication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-howto-slavebaseconfig.html" title="19.1.2.2 Setting the Replica Configuration">
Section 19.1.2.2, “Setting the Replica Configuration”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-gtids-functions.html" title="19.1.3.8 Stored Function Examples to Manipulate GTIDs">
Section 19.1.3.8, “Stored Function Examples to Manipulate GTIDs”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log.html" title="7.4.4 The Binary Log">
Section 7.4.4, “The Binary Log”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-what-is-new.html" title="25.2.4 What is New in MySQL NDB Cluster 8.4">
Section 25.2.4, “What is New in MySQL NDB Cluster 8.4”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
log_slave_updates
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-binary-log.html" title="19.1.6.4 Binary Logging Options and Variables">
Section 19.1.6.4, “Binary Logging Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
log_slow_admin_statements
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="slow-query-log.html" title="7.4.5 The Slow Query Log">
Section 7.4.5, “The Slow Query Log”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
log_slow_extra
</h3>
<dl>
<dt>
<a class="xref" href="audit-log-file-formats.html" title="8.4.5.4 Audit Log File Formats">
Section 8.4.5.4, “Audit Log File Formats”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="audit-log-logging-configuration.html" title="8.4.5.5 Configuring Audit Logging Characteristics">
Section 8.4.5.5, “Configuring Audit Logging Characteristics”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="slow-query-log.html" title="7.4.5 The Slow Query Log">
Section 7.4.5, “The Slow Query Log”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
log_slow_replica_statements
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="slow-query-log.html" title="7.4.5 The Slow Query Log">
Section 7.4.5, “The Slow Query Log”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
log_slow_slave_statements
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
log_statements_unsafe_for_binlog
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-binary-log.html" title="19.1.6.4 Binary Logging Options and Variables">
Section 19.1.6.4, “Binary Logging Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
log_syslog_facility
</h3>
<dl>
<dt>
<a class="xref" href="mysqld-safe.html" title="6.3.2 mysqld_safe — MySQL Server Startup Script">
Section 6.3.2, “mysqld_safe — MySQL Server Startup Script”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
log_syslog_tag
</h3>
<dl>
<dt>
<a class="xref" href="mysqld-safe.html" title="6.3.2 mysqld_safe — MySQL Server Startup Script">
Section 6.3.2, “mysqld_safe — MySQL Server Startup Script”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
log_throttle_queries_not_using_indexes
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="slow-query-log.html" title="7.4.5 The Slow Query Log">
Section 7.4.5, “The Slow Query Log”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
log_timestamps
</h3>
<dl>
<dt>
<a class="xref" href="error-log-format.html" title="7.4.2.9 Error Log Output Format">
Section 7.4.2.9, “Error Log Output Format”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-error-log-table.html" title="29.12.22.2 The error_log Table">
Section 29.12.22.2, “The error_log Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="query-log.html" title="7.4.3 The General Query Log">
Section 7.4.3, “The General Query Log”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="slow-query-log.html" title="7.4.5 The Slow Query Log">
Section 7.4.5, “The Slow Query Log”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
long_query_time
</h3>
<dl>
<dt>
<a class="xref" href="server-logs.html" title="7.4 MySQL Server Logs">
Section 7.4, “MySQL Server Logs”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysqladmin.html" title="6.5.2 mysqladmin — A MySQL Server Administration Program">
Section 6.5.2, “mysqladmin — A MySQL Server Administration Program”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysqldump.html" title="6.5.4 mysqldump — A Database Backup Program">
Section 6.5.4, “mysqldump — A Database Backup Program”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-status-variables.html" title="7.1.10 Server Status Variables">
Section 7.1.10, “Server Status Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="slow-query-log.html" title="7.4.5 The Slow Query Log">
Section 7.4.5, “The Slow Query Log”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
low_priority_updates
</h3>
<dl>
<dt>
<a class="xref" href="faqs-replication.html" title="A.14 MySQL 8.4 FAQ: Replication">
Section A.14, “MySQL 8.4 FAQ: Replication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="table-locking.html" title="10.11.2 Table Locking Issues">
Section 10.11.2, “Table Locking Issues”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
lower_case_file_system
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
lower_case_table_names
</h3>
<dl>
<dt>
<a class="xref" href="mysql-configurator-workflow-server.html#server-advanced-options" title="2.3.2.1.7 Advanced Options">
Section 2.3.2.1.7, “Advanced Options”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="create-table-foreign-keys.html" title="15.1.20.5 FOREIGN KEY Constraints">
Section 15.1.20.5, “FOREIGN KEY Constraints”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="grant.html" title="15.7.1.6 GRANT Statement">
Section 15.7.1.6, “GRANT Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-requirements.html" title="20.3.1 Group Replication Requirements">
Section 20.3.1, “Group Replication Requirements”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-rules.html" title="19.2.5 How Servers Evaluate Replication Filtering Rules">
Section 19.2.5, “How Servers Evaluate Replication Filtering Rules”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="bug-reports.html" title="1.6 How to Report Bugs or Problems">
Section 1.6, “How to Report Bugs or Problems”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="identifier-case-sensitivity.html" title="11.2.3 Identifier Case Sensitivity">
Section 11.2.3, “Identifier Case Sensitivity”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="import-table.html" title="15.2.6 IMPORT TABLE Statement">
Section 15.2.6, “IMPORT TABLE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-table-import.html" title="17.6.1.3 Importing InnoDB Tables">
Section 17.6.1.3, “Importing InnoDB Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-migration.html" title="17.6.1.4 Moving or Copying InnoDB Tables">
Section 17.6.1.4, “Moving or Copying InnoDB Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="upgrade-prerequisites.html" title="3.6 Preparing Your Installation for Upgrade">
Section 3.6, “Preparing Your Installation for Upgrade”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-variables.html" title="19.5.1.39 Replication and Variables">
Section 19.5.1.39, “Replication and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="revoke.html" title="15.7.1.8 REVOKE Statement">
Section 15.7.1.8, “REVOKE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="show-tables.html" title="15.7.7.39 SHOW TABLES Statement">
Section 15.7.7.39, “SHOW TABLES Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-innodb-columns-table.html" title="28.4.9 The INFORMATION_SCHEMA INNODB_COLUMNS Table">
Section 28.4.9, “The INFORMATION_SCHEMA INNODB_COLUMNS Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-innodb-tables-table.html" title="28.4.23 The INFORMATION_SCHEMA INNODB_TABLES Table">
Section 28.4.23, “The INFORMATION_SCHEMA INNODB_TABLES Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="charset-collation-information-schema.html" title="12.8.7 Using Collation in INFORMATION_SCHEMA Searches">
Section 12.8.7, “Using Collation in INFORMATION_SCHEMA Searches”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<a name="sysvar-index-M">
</a>
<h3 class="title">
M
</h3>
<p>
[
<a class="link" href="dynindex-sysvar.html#sysvar-index-top">
index top
</a>
]
</p>
<dl>
<dt>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
mandatory_roles
</h3>
<dl>
<dt>
<a class="xref" href="account-categories.html" title="8.2.11 Account Categories">
Section 8.2.11, “Account Categories”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="drop-role.html" title="15.7.1.4 DROP ROLE Statement">
Section 15.7.1.4, “DROP ROLE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="drop-user.html" title="15.7.1.5 DROP USER Statement">
Section 15.7.1.5, “DROP USER Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="privileges-provided.html" title="8.2.2 Privileges Provided by MySQL">
Section 8.2.2, “Privileges Provided by MySQL”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="revoke.html" title="15.7.1.8 REVOKE Statement">
Section 15.7.1.8, “REVOKE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="set-role.html" title="15.7.1.11 SET ROLE Statement">
Section 15.7.1.11, “SET ROLE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="show-grants.html" title="15.7.7.22 SHOW GRANTS Statement">
Section 15.7.7.22, “SHOW GRANTS Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="system-variable-privileges.html" title="7.1.9.1 System Variable Privileges">
Section 7.1.9.1, “System Variable Privileges”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="roles.html" title="8.2.10 Using Roles">
Section 8.2.10, “Using Roles”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
master_verify_checksum
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-binary-log.html" title="19.1.6.4 Binary Logging Options and Variables">
Section 19.1.6.4, “Binary Logging Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="glossary.html" title="MySQL Glossary">
MySQL Glossary
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
max_allowed_packet
</h3>
<dl>
<dt>
<a class="xref" href="aggregate-functions.html" title="14.19.1 Aggregate Function Descriptions">
Section 14.19.1, “Aggregate Function Descriptions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log-transaction-compression.html#binary-log-transaction-compression-enabled" title="7.4.4.5.1 Behaviors When Binary Log Transaction Compression is Enabled">
Section 7.4.4.5.1, “Behaviors When Binary Log Transaction Compression is Enabled”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="clone-plugin-remote.html" title="7.6.7.3 Cloning Remote Data">
Section 7.6.7.3, “Cloning Remote Data”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="communication-errors.html" title="B.3.2.9 Communication Errors and Aborted Connections">
Section B.3.2.9, “Communication Errors and Aborted Connections”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="comparison-operators.html" title="14.4.2 Comparison Functions and Operators">
Section 14.4.2, “Comparison Functions and Operators”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="storage-requirements.html" title="13.7 Data Type Storage Requirements">
Section 13.7, “Data Type Storage Requirements”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="deleting-from-related-tables.html" title="B.3.4.6 Deleting Rows from Related Tables">
Section B.3.4.6, “Deleting Rows from Related Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="memory-use.html" title="10.12.3.1 How MySQL Uses Memory">
Section 10.12.3.1, “How MySQL Uses Memory”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="error-lost-connection.html" title="B.3.2.3 Lost connection to MySQL server">
Section B.3.2.3, “Lost connection to MySQL server”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="gone-away.html" title="B.3.2.7 MySQL server has gone away">
Section B.3.2.7, “MySQL server has gone away”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysqldump.html" title="6.5.4 mysqldump — A Database Backup Program">
Section 6.5.4, “mysqldump — A Database Backup Program”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-replication-conflict-resolution.html" title="25.7.12 NDB Cluster Replication Conflict Resolution">
Section 25.7.12, “NDB Cluster Replication Conflict Resolution”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="packet-too-large.html" title="B.3.2.8 Packet Too Large">
Section B.3.2.8, “Packet Too Large”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-max-allowed-packet.html" title="19.5.1.20 Replication and max_allowed_packet">
Section 19.5.1.20, “Replication and max_allowed_packet”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="string-functions.html" title="14.8 String Functions and Operators">
Section 14.8, “String Functions and Operators”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="blob.html" title="13.3.4 The BLOB and TEXT Types">
Section 13.3.4, “The BLOB and TEXT Types”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="json.html" title="13.5 The JSON Data Type">
Section 13.5, “The JSON Data Type”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="version-tokens-usage.html" title="7.6.6.3 Using Version Tokens">
Section 7.6.6.3, “Using Version Tokens”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="x-plugin-options-system-variables.html" title="22.5.6.2 X Plugin Options and System Variables">
Section 22.5.6.2, “X Plugin Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
max_binlog_cache_size
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-binary-log.html" title="19.1.6.4 Binary Logging Options and Variables">
Section 19.1.6.4, “Binary Logging Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="memory-use.html" title="10.12.3.1 How MySQL Uses Memory">
Section 10.12.3.1, “How MySQL Uses Memory”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log.html" title="7.4.4 The Binary Log">
Section 7.4.4, “The Binary Log”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
max_binlog_size
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-binary-log.html" title="19.1.6.4 Binary Logging Options and Variables">
Section 19.1.6.4, “Binary Logging Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-gtids-concepts.html" title="19.1.3.1 GTID Format and Storage">
Section 19.1.3.1, “GTID Format and Storage”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-logs.html" title="7.4 MySQL Server Logs">
Section 7.4, “MySQL Server Logs”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="log-file-maintenance.html" title="7.4.6 Server Log Maintenance">
Section 7.4.6, “Server Log Maintenance”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log.html" title="7.4.4 The Binary Log">
Section 7.4.4, “The Binary Log”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replica-logs-relaylog.html" title="19.2.4.1 The Relay Log">
Section 19.2.4.1, “The Relay Log”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
max_binlog_stmt_cache_size
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-binary-log.html" title="19.1.6.4 Binary Logging Options and Variables">
Section 19.1.6.4, “Binary Logging Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="memory-use.html" title="10.12.3.1 How MySQL Uses Memory">
Section 10.12.3.1, “How MySQL Uses Memory”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
max_connect_errors
</h3>
<dl>
<dt>
<a class="xref" href="host-cache.html" title="7.1.12.3 DNS Lookups and the Host Cache">
Section 7.1.12.3, “DNS Lookups and the Host Cache”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-host-cache-table.html" title="29.12.22.3 The host_cache Table">
Section 29.12.22.3, “The host_cache Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
max_connections
</h3>
<dl>
<dt>
<a class="xref" href="administrative-connection-interface.html" title="7.1.12.2 Administrative Connection Management">
Section 7.1.12.2, “Administrative Connection Management”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-binary-log.html" title="19.1.6.4 Binary Logging Options and Variables">
Section 19.1.6.4, “Binary Logging Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="connection-interfaces.html" title="7.1.12.1 Connection Interfaces">
Section 7.1.12.1, “Connection Interfaces”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="using-gdb-on-mysqld.html" title="7.9.1.4 Debugging mysqld under gdb">
Section 7.9.1.4, “Debugging mysqld under gdb”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="data-dictionary-object-cache.html" title="16.4 Dictionary Object Cache">
Section 16.4, “Dictionary Object Cache”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="not-enough-file-handles.html" title="B.3.2.16 File Not Found and Similar Errors">
Section B.3.2.16, “File Not Found and Similar Errors”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="table-cache.html" title="10.4.3.1 How MySQL Opens and Closes Tables">
Section 10.4.3.1, “How MySQL Opens and Closes Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="privileges-provided.html" title="8.2.2 Privileges Provided by MySQL">
Section 8.2.2, “Privileges Provided by MySQL”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-status-variables.html" title="7.1.10 Server Status Variables">
Section 7.1.10, “Server Status Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-processlist-table.html" title="29.12.22.7 The processlist Table">
Section 29.12.22.7, “The processlist Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="thread-pool-operation.html" title="7.6.3.3 Thread Pool Operation">
Section 7.6.3.3, “Thread Pool Operation”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="too-many-connections.html" title="B.3.2.5 Too many connections">
Section B.3.2.5, “Too many connections”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="x-plugin-options-system-variables.html" title="22.5.6.2 X Plugin Options and System Variables">
Section 22.5.6.2, “X Plugin Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
max_delayed_threads
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
max_digest_length
</h3>
<dl>
<dt>
<a class="xref" href="encryption-functions.html" title="14.13 Encryption and Compression Functions">
Section 14.13, “Encryption and Compression Functions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="memory-use.html" title="10.12.3.1 How MySQL Uses Memory">
Section 10.12.3.1, “How MySQL Uses Memory”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-statement-digests.html" title="29.10 Performance Schema Statement Digests and Sampling">
Section 29.10, “Performance Schema Statement Digests and Sampling”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="firewall-usage.html" title="8.4.7.3 Using MySQL Enterprise Firewall">
Section 8.4.7.3, “Using MySQL Enterprise Firewall”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
max_error_count
</h3>
<dl>
<dt>
<a class="xref" href="load-data.html" title="15.2.9 LOAD DATA Statement">
Section 15.2.9, “LOAD DATA Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="resignal.html" title="15.6.7.4 RESIGNAL Statement">
Section 15.6.7.4, “RESIGNAL Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="show-errors.html" title="15.7.7.18 SHOW ERRORS Statement">
Section 15.7.7.18, “SHOW ERRORS Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="show-warnings.html" title="15.7.7.42 SHOW WARNINGS Statement">
Section 15.7.7.42, “SHOW WARNINGS Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="diagnostics-area.html" title="15.6.7.7 The MySQL Diagnostics Area">
Section 15.6.7.7, “The MySQL Diagnostics Area”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
max_execution_time
</h3>
<dl>
<dt>
<a class="xref" href="optimizer-hints.html" title="10.9.3 Optimizer Hints">
Section 10.9.3, “Optimizer Hints”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-status-variables.html" title="7.1.10 Server Status Variables">
Section 7.1.10, “Server Status Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="with.html" title="15.2.20 WITH (Common Table Expressions)">
Section 15.2.20, “WITH (Common Table Expressions)”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
max_heap_table_size
</h3>
<dl>
<dt>
<a class="xref" href="memory-use.html" title="10.12.3.1 How MySQL Uses Memory">
Section 10.12.3.1, “How MySQL Uses Memory”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="internal-temporary-tables.html" title="10.4.4 Internal Temporary Table Use in MySQL">
Section 10.4.4, “Internal Temporary Table Use in MySQL”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="table-size-limit.html" title="10.4.6 Limits on Table Size">
Section 10.4.6, “Limits on Table Size”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-memory.html" title="19.5.1.21 Replication and MEMORY Tables">
Section 19.5.1.21, “Replication and MEMORY Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-variables.html" title="19.5.1.39 Replication and Variables">
Section 19.5.1.39, “Replication and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="cursor-restrictions.html" title="15.6.6.5 Restrictions on Server-Side Cursors">
Section 15.6.6.5, “Restrictions on Server-Side Cursors”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="memory-storage-engine.html" title="18.3 The MEMORY Storage Engine">
Section 18.3, “The MEMORY Storage Engine”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
max_insert_delayed_threads
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
max_join_size
</h3>
<dl>
<dt>
<a class="xref" href="explain-output.html" title="10.8.2 EXPLAIN Output Format">
Section 10.8.2, “EXPLAIN Output Format”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-tips.html" title="6.5.1.6 mysql Client Tips">
Section 6.5.1.6, “mysql Client Tips”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="set-variable.html" title="15.7.6.1 SET Syntax for Variable Assignment">
Section 15.7.6.1, “SET Syntax for Variable Assignment”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
max_length_for_sort_data
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
max_points_in_geometry
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="spatial-operator-functions.html" title="14.16.8 Spatial Operator Functions">
Section 14.16.8, “Spatial Operator Functions”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
max_prepared_stmt_count
</h3>
<dl>
<dt>
<a class="xref" href="statement-caching.html" title="10.10.3 Caching of Prepared Statements and Stored Programs">
Section 10.10.3, “Caching of Prepared Statements and Stored Programs”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="deallocate-prepare.html" title="15.5.3 DEALLOCATE PREPARE Statement">
Section 15.5.3, “DEALLOCATE PREPARE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="sql-prepared-statements.html" title="15.5 Prepared Statements">
Section 15.5, “Prepared Statements”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-status-variables.html" title="7.1.10 Server Status Variables">
Section 7.1.10, “Server Status Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
max_relay_log_size
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-binary-log.html" title="19.1.6.4 Binary Logging Options and Variables">
Section 19.1.6.4, “Binary Logging Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replica-logs-relaylog.html" title="19.2.4.1 The Relay Log">
Section 19.2.4.1, “The Relay Log”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
max_seeks_for_key
</h3>
<dl>
<dt>
<a class="xref" href="analyze-table.html" title="15.7.3.1 ANALYZE TABLE Statement">
Section 15.7.3.1, “ANALYZE TABLE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
max_sort_length
</h3>
<dl>
<dt>
<a class="xref" href="known-issues.html" title="B.3.7 Known Issues in MySQL">
Section B.3.7, “Known Issues in MySQL”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="order-by-optimization.html" title="10.2.1.16 ORDER BY Optimization">
Section 10.2.1.16, “ORDER BY Optimization”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="select.html" title="15.2.13 SELECT Statement">
Section 15.2.13, “SELECT Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="blob.html" title="13.3.4 The BLOB and TEXT Types">
Section 13.3.4, “The BLOB and TEXT Types”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="json.html" title="13.5 The JSON Data Type">
Section 13.5, “The JSON Data Type”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
max_sp_recursion_depth
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="stored-routines-syntax.html" title="27.2.1 Stored Routine Syntax">
Section 27.2.1, “Stored Routine Syntax”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
max_user_connections
</h3>
<dl>
<dt>
<a class="xref" href="alter-user.html" title="15.7.1.1 ALTER USER Statement">
Section 15.7.1.1, “ALTER USER Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="create-user.html" title="15.7.1.3 CREATE USER Statement">
Section 15.7.1.3, “CREATE USER Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="flush.html" title="15.7.8.3 FLUSH Statement">
Section 15.7.8.3, “FLUSH Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="security-against-attack.html" title="8.1.3 Making MySQL Secure Against Attackers">
Section 8.1.3, “Making MySQL Secure Against Attackers”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="user-resources.html" title="8.2.21 Setting Account Resource Limits">
Section 8.2.21, “Setting Account Resource Limits”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
max_write_lock_count
</h3>
<dl>
<dt>
<a class="xref" href="lock-tables.html" title="15.3.6 LOCK TABLES and UNLOCK TABLES Statements">
Section 15.3.6, “LOCK TABLES and UNLOCK TABLES Statements”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="metadata-locking.html" title="10.11.4 Metadata Locking">
Section 10.11.4, “Metadata Locking”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="table-locking.html" title="10.11.2 Table Locking Issues">
Section 10.11.2, “Table Locking Issues”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
mecab_rc_file
</h3>
<dl>
<dt>
<a class="xref" href="fulltext-search-mecab.html" title="14.9.9 MeCab Full-Text Parser Plugin">
Section 14.9.9, “MeCab Full-Text Parser Plugin”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
min_examined_row_limit
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="slow-query-log.html" title="7.4.5 The Slow Query Log">
Section 7.4.5, “The Slow Query Log”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
myisam_data_pointer_size
</h3>
<dl>
<dt>
<a class="xref" href="create-table.html" title="15.1.20 CREATE TABLE Statement">
Section 15.1.20, “CREATE TABLE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="table-size-limit.html" title="10.4.6 Limits on Table Size">
Section 10.4.6, “Limits on Table Size”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
myisam_max_sort_file_size
</h3>
<dl>
<dt>
<a class="xref" href="myisam-start.html" title="18.2.1 MyISAM Startup Options">
Section 18.2.1, “MyISAM Startup Options”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="repair-table-optimization.html" title="10.6.3 Optimizing REPAIR TABLE Statements">
Section 10.6.3, “Optimizing REPAIR TABLE Statements”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
myisam_mmap_size
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
myisam_recover_options
</h3>
<dl>
<dt>
<a class="xref" href="myisam-start.html" title="18.2.1 MyISAM Startup Options">
Section 18.2.1, “MyISAM Startup Options”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="optimizing-queries-myisam.html" title="10.6.1 Optimizing MyISAM Queries">
Section 10.6.1, “Optimizing MyISAM Queries”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="myisam-maintenance-schedule.html" title="9.6.5 Setting Up a MyISAM Table Maintenance Schedule">
Section 9.6.5, “Setting Up a MyISAM Table Maintenance Schedule”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="table-corruption.html" title="B.3.2.17 Table-Corruption Issues">
Section B.3.2.17, “Table-Corruption Issues”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="myisam-storage-engine.html" title="18.2 The MyISAM Storage Engine">
Section 18.2, “The MyISAM Storage Engine”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="using-log-files.html" title="7.9.1.6 Using Server Logs to Find Causes of Errors in mysqld">
Section 7.9.1.6, “Using Server Logs to Find Causes of Errors in mysqld”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
myisam_sort_buffer_size
</h3>
<dl>
<dt>
<a class="xref" href="alter-table.html" title="15.1.9 ALTER TABLE Statement">
Section 15.1.9, “ALTER TABLE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="myisam-start.html" title="18.2.1 MyISAM Startup Options">
Section 18.2.1, “MyISAM Startup Options”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="repair-table-optimization.html" title="10.6.3 Optimizing REPAIR TABLE Statements">
Section 10.6.3, “Optimizing REPAIR TABLE Statements”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
myisam_stats_method
</h3>
<dl>
<dt>
<a class="xref" href="index-statistics.html" title="10.3.8 InnoDB and MyISAM Index Statistics Collection">
Section 10.3.8, “InnoDB and MyISAM Index Statistics Collection”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
myisam_use_mmap
</h3>
<dl>
<dt>
<a class="xref" href="memory-use.html" title="10.12.3.1 How MySQL Uses Memory">
Section 10.12.3.1, “How MySQL Uses Memory”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
mysql_firewall_database
</h3>
<dl>
<dt>
<a class="xref" href="firewall-reference.html" title="8.4.7.4 MySQL Enterprise Firewall Reference">
Section 8.4.7.4, “MySQL Enterprise Firewall Reference”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
mysql_firewall_mode
</h3>
<dl>
<dt>
<a class="xref" href="firewall-reference.html" title="8.4.7.4 MySQL Enterprise Firewall Reference">
Section 8.4.7.4, “MySQL Enterprise Firewall Reference”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="firewall-usage.html" title="8.4.7.3 Using MySQL Enterprise Firewall">
Section 8.4.7.3, “Using MySQL Enterprise Firewall”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
mysql_firewall_reload_interval_seconds
</h3>
<dl>
<dt>
<a class="xref" href="firewall-reference.html" title="8.4.7.4 MySQL Enterprise Firewall Reference">
Section 8.4.7.4, “MySQL Enterprise Firewall Reference”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="firewall-usage.html" title="8.4.7.3 Using MySQL Enterprise Firewall">
Section 8.4.7.3, “Using MySQL Enterprise Firewall”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
mysql_firewall_trace
</h3>
<dl>
<dt>
<a class="xref" href="firewall-reference.html" title="8.4.7.4 MySQL Enterprise Firewall Reference">
Section 8.4.7.4, “MySQL Enterprise Firewall Reference”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="firewall-usage.html" title="8.4.7.3 Using MySQL Enterprise Firewall">
Section 8.4.7.3, “Using MySQL Enterprise Firewall”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
mysql_native_password_proxy_users
</h3>
<dl>
<dt>
<a class="xref" href="proxy-users.html" title="8.2.19 Proxy Users">
Section 8.2.19, “Proxy Users”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
mysqlx_bind_address
</h3>
<dl>
<dt>
<a class="xref" href="network-namespace-support.html" title="7.1.14 Network Namespace Support">
Section 7.1.14, “Network Namespace Support”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="x-plugin-options-system-variables.html" title="22.5.6.2 X Plugin Options and System Variables">
Section 22.5.6.2, “X Plugin Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="x-plugin-status-variables.html" title="22.5.6.3 X Plugin Status Variables">
Section 22.5.6.3, “X Plugin Status Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
mysqlx_compression_algorithms
</h3>
<dl>
<dt>
<a class="xref" href="x-plugin-connection-compression.html" title="22.5.5 Connection Compression with X Plugin">
Section 22.5.5, “Connection Compression with X Plugin”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="x-plugin-options-system-variables.html" title="22.5.6.2 X Plugin Options and System Variables">
Section 22.5.6.2, “X Plugin Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="x-plugin-status-variables.html" title="22.5.6.3 X Plugin Status Variables">
Section 22.5.6.3, “X Plugin Status Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
mysqlx_connect_timeout
</h3>
<dl>
<dt>
<a class="xref" href="x-plugin-options-system-variables.html" title="22.5.6.2 X Plugin Options and System Variables">
Section 22.5.6.2, “X Plugin Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
mysqlx_deflate_default_compression_level
</h3>
<dl>
<dt>
<a class="xref" href="x-plugin-connection-compression.html" title="22.5.5 Connection Compression with X Plugin">
Section 22.5.5, “Connection Compression with X Plugin”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="x-plugin-options-system-variables.html" title="22.5.6.2 X Plugin Options and System Variables">
Section 22.5.6.2, “X Plugin Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
mysqlx_deflate_max_client_compression_level
</h3>
<dl>
<dt>
<a class="xref" href="x-plugin-connection-compression.html" title="22.5.5 Connection Compression with X Plugin">
Section 22.5.5, “Connection Compression with X Plugin”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="x-plugin-options-system-variables.html" title="22.5.6.2 X Plugin Options and System Variables">
Section 22.5.6.2, “X Plugin Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
mysqlx_document_id_unique_prefix
</h3>
<dl>
<dt>
<a class="xref" href="x-plugin-options-system-variables.html" title="22.5.6.2 X Plugin Options and System Variables">
Section 22.5.6.2, “X Plugin Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
mysqlx_enable_hello_notice
</h3>
<dl>
<dt>
<a class="xref" href="x-plugin-options-system-variables.html" title="22.5.6.2 X Plugin Options and System Variables">
Section 22.5.6.2, “X Plugin Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
mysqlx_idle_worker_thread_timeout
</h3>
<dl>
<dt>
<a class="xref" href="x-plugin-options-system-variables.html" title="22.5.6.2 X Plugin Options and System Variables">
Section 22.5.6.2, “X Plugin Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
mysqlx_interactive_timeout
</h3>
<dl>
<dt>
<a class="xref" href="x-plugin-options-system-variables.html" title="22.5.6.2 X Plugin Options and System Variables">
Section 22.5.6.2, “X Plugin Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
mysqlx_lz
</h3>
<dl>
<dt>
<a class="xref" href="x-plugin-connection-compression.html" title="22.5.5 Connection Compression with X Plugin">
Section 22.5.5, “Connection Compression with X Plugin”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="x-plugin-options-system-variables.html" title="22.5.6.2 X Plugin Options and System Variables">
Section 22.5.6.2, “X Plugin Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
mysqlx_max_allowed_packet
</h3>
<dl>
<dt>
<a class="xref" href="x-plugin-connection-compression.html" title="22.5.5 Connection Compression with X Plugin">
Section 22.5.5, “Connection Compression with X Plugin”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="x-plugin-options-system-variables.html" title="22.5.6.2 X Plugin Options and System Variables">
Section 22.5.6.2, “X Plugin Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
mysqlx_max_connections
</h3>
<dl>
<dt>
<a class="xref" href="x-plugin-options-system-variables.html" title="22.5.6.2 X Plugin Options and System Variables">
Section 22.5.6.2, “X Plugin Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
mysqlx_min_worker_threads
</h3>
<dl>
<dt>
<a class="xref" href="x-plugin-options-system-variables.html" title="22.5.6.2 X Plugin Options and System Variables">
Section 22.5.6.2, “X Plugin Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
mysqlx_port
</h3>
<dl>
<dt>
<a class="xref" href="clone-plugin-limitations.html" title="7.6.7.14 Clone Plugin Limitations">
Section 7.6.7.14, “Clone Plugin Limitations”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="clone.html" title="15.7.5 CLONE Statement">
Section 15.7.5, “CLONE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="clone-plugin-remote.html" title="7.6.7.3 Cloning Remote Data">
Section 7.6.7.3, “Cloning Remote Data”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-shell-tutorial-javascript-shell.html" title="22.3.1 MySQL Shell">
Section 22.3.1, “MySQL Shell”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-shell-tutorial-python-shell.html" title="22.4.1 MySQL Shell">
Section 22.4.1, “MySQL Shell”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="source-configuration-options.html" title="2.8.7 MySQL Source-Configuration Options">
Section 2.8.7, “MySQL Source-Configuration Options”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="selinux-context-mysql-feature-ports.html" title="8.7.5.2 Setting the TCP Port Context for MySQL Features">
Section 8.7.5.2, “Setting the TCP Port Context for MySQL Features”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="x-plugin-options-system-variables.html" title="22.5.6.2 X Plugin Options and System Variables">
Section 22.5.6.2, “X Plugin Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
mysqlx_port_open_timeout
</h3>
<dl>
<dt>
<a class="xref" href="x-plugin-options-system-variables.html" title="22.5.6.2 X Plugin Options and System Variables">
Section 22.5.6.2, “X Plugin Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
mysqlx_read_timeout
</h3>
<dl>
<dt>
<a class="xref" href="x-plugin-options-system-variables.html" title="22.5.6.2 X Plugin Options and System Variables">
Section 22.5.6.2, “X Plugin Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
mysqlx_socket
</h3>
<dl>
<dt>
<a class="xref" href="x-plugin-options-system-variables.html" title="22.5.6.2 X Plugin Options and System Variables">
Section 22.5.6.2, “X Plugin Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
mysqlx_ssl_ca
</h3>
<dl>
<dt>
<a class="xref" href="x-plugin-options-system-variables.html" title="22.5.6.2 X Plugin Options and System Variables">
Section 22.5.6.2, “X Plugin Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
mysqlx_ssl_capath
</h3>
<dl>
<dt>
<a class="xref" href="x-plugin-options-system-variables.html" title="22.5.6.2 X Plugin Options and System Variables">
Section 22.5.6.2, “X Plugin Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
mysqlx_ssl_cert
</h3>
<dl>
<dt>
<a class="xref" href="x-plugin-options-system-variables.html" title="22.5.6.2 X Plugin Options and System Variables">
Section 22.5.6.2, “X Plugin Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
mysqlx_ssl_cipher
</h3>
<dl>
<dt>
<a class="xref" href="x-plugin-options-system-variables.html" title="22.5.6.2 X Plugin Options and System Variables">
Section 22.5.6.2, “X Plugin Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
mysqlx_ssl_crl
</h3>
<dl>
<dt>
<a class="xref" href="x-plugin-options-system-variables.html" title="22.5.6.2 X Plugin Options and System Variables">
Section 22.5.6.2, “X Plugin Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
mysqlx_ssl_crlpath
</h3>
<dl>
<dt>
<a class="xref" href="x-plugin-options-system-variables.html" title="22.5.6.2 X Plugin Options and System Variables">
Section 22.5.6.2, “X Plugin Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
mysqlx_ssl_key
</h3>
<dl>
<dt>
<a class="xref" href="x-plugin-options-system-variables.html" title="22.5.6.2 X Plugin Options and System Variables">
Section 22.5.6.2, “X Plugin Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
mysqlx_wait_timeout
</h3>
<dl>
<dt>
<a class="xref" href="x-plugin-options-system-variables.html" title="22.5.6.2 X Plugin Options and System Variables">
Section 22.5.6.2, “X Plugin Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
mysqlx_write_timeout
</h3>
<dl>
<dt>
<a class="xref" href="x-plugin-options-system-variables.html" title="22.5.6.2 X Plugin Options and System Variables">
Section 22.5.6.2, “X Plugin Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
mysqlx_zstd_default_compression_level
</h3>
<dl>
<dt>
<a class="xref" href="x-plugin-connection-compression.html" title="22.5.5 Connection Compression with X Plugin">
Section 22.5.5, “Connection Compression with X Plugin”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="x-plugin-options-system-variables.html" title="22.5.6.2 X Plugin Options and System Variables">
Section 22.5.6.2, “X Plugin Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
mysqlx_zstd_max_client_compression_level
</h3>
<dl>
<dt>
<a class="xref" href="x-plugin-connection-compression.html" title="22.5.5 Connection Compression with X Plugin">
Section 22.5.5, “Connection Compression with X Plugin”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="x-plugin-options-system-variables.html" title="22.5.6.2 X Plugin Options and System Variables">
Section 22.5.6.2, “X Plugin Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<a name="sysvar-index-N">
</a>
<h3 class="title">
N
</h3>
<p>
[
<a class="link" href="dynindex-sysvar.html#sysvar-index-top">
index top
</a>
]
</p>
<dl>
<dt>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
named_pipe
</h3>
<dl>
<dt>
<a class="xref" href="can-not-connect-to-server.html" title="B.3.2.2 Can't connect to [local] MySQL server">
Section B.3.2.2, “Can't connect to [local] MySQL server”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="connection-options.html" title="6.2.3 Command Options for Connecting to the Server">
Section 6.2.3, “Command Options for Connecting to the Server”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="connecting.html" title="6.2.4 Connecting to the MySQL Server Using Command Options">
Section 6.2.4, “Connecting to the MySQL Server Using Command Options”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-command-options.html" title="6.5.1.1 mysql Client Options">
Section 6.5.1.1, “mysql Client Options”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-migrate-keyring.html" title="6.6.8 mysql_migrate_keyring — Keyring Key Migration Utility">
Section 6.6.8, “mysql_migrate_keyring — Keyring Key Migration Utility”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-secure-installation.html" title="6.4.2 mysql_secure_installation — Improve MySQL Installation Security">
Section 6.4.2, “mysql_secure_installation — Improve MySQL Installation Security”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysqladmin.html" title="6.5.2 mysqladmin — A MySQL Server Administration Program">
Section 6.5.2, “mysqladmin — A MySQL Server Administration Program”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysqlbinlog.html" title="6.6.9 mysqlbinlog — Utility for Processing Binary Log Files">
Section 6.6.9, “mysqlbinlog — Utility for Processing Binary Log Files”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysqlcheck.html" title="6.5.3 mysqlcheck — A Table Maintenance Program">
Section 6.5.3, “mysqlcheck — A Table Maintenance Program”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysqldump.html" title="6.5.4 mysqldump — A Database Backup Program">
Section 6.5.4, “mysqldump — A Database Backup Program”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysqlimport.html" title="6.5.5 mysqlimport — A Data Import Program">
Section 6.5.5, “mysqlimport — A Data Import Program”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysqlshow.html" title="6.5.6 mysqlshow — Display Database, Table, and Column Information">
Section 6.5.6, “mysqlshow — Display Database, Table, and Column Information”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysqlslap.html" title="6.5.7 mysqlslap — A Load Emulation Client">
Section 6.5.7, “mysqlslap — A Load Emulation Client”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="resetting-permissions.html#resetting-permissions-generic" title="B.3.3.2.3 Resetting the Root Password: Generic Instructions">
Section B.3.3.2.3, “Resetting the Root Password: Generic Instructions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="windows-select-server.html" title="2.3.3.3 Selecting a MySQL Server Type">
Section 2.3.3.3, “Selecting a MySQL Server Type”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="features.html" title="1.2.2 The Main Features of MySQL">
Section 1.2.2, “The Main Features of MySQL”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-configurator-workflow-server.html#server-type-network" title="2.3.2.1.2 Type and Networking">
Section 2.3.2.1.2, “Type and Networking”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
named_pipe_full_access_group
</h3>
<dl>
<dt>
<a class="xref" href="connection-options.html" title="6.2.3 Command Options for Connecting to the Server">
Section 6.2.3, “Command Options for Connecting to the Server”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="connecting.html" title="6.2.4 Connecting to the MySQL Server Using Command Options">
Section 6.2.4, “Connecting to the MySQL Server Using Command Options”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="transport-protocols.html" title="6.2.7 Connection Transport Protocols">
Section 6.2.7, “Connection Transport Protocols”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-command-options.html" title="6.5.1.1 mysql Client Options">
Section 6.5.1.1, “mysql Client Options”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-migrate-keyring.html" title="6.6.8 mysql_migrate_keyring — Keyring Key Migration Utility">
Section 6.6.8, “mysql_migrate_keyring — Keyring Key Migration Utility”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-secure-installation.html" title="6.4.2 mysql_secure_installation — Improve MySQL Installation Security">
Section 6.4.2, “mysql_secure_installation — Improve MySQL Installation Security”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysqladmin.html" title="6.5.2 mysqladmin — A MySQL Server Administration Program">
Section 6.5.2, “mysqladmin — A MySQL Server Administration Program”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysqlbinlog.html" title="6.6.9 mysqlbinlog — Utility for Processing Binary Log Files">
Section 6.6.9, “mysqlbinlog — Utility for Processing Binary Log Files”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysqlcheck.html" title="6.5.3 mysqlcheck — A Table Maintenance Program">
Section 6.5.3, “mysqlcheck — A Table Maintenance Program”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysqldump.html" title="6.5.4 mysqldump — A Database Backup Program">
Section 6.5.4, “mysqldump — A Database Backup Program”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysqlimport.html" title="6.5.5 mysqlimport — A Data Import Program">
Section 6.5.5, “mysqlimport — A Data Import Program”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysqlshow.html" title="6.5.6 mysqlshow — Display Database, Table, and Column Information">
Section 6.5.6, “mysqlshow — Display Database, Table, and Column Information”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysqlslap.html" title="6.5.7 mysqlslap — A Load Emulation Client">
Section 6.5.7, “mysqlslap — A Load Emulation Client”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_autoincrement_prefetch_sz
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-programs-ndb-import.html" title="25.5.13 ndb_import — Import CSV Data Into NDB">
Section 25.5.13, “ndb_import — Import CSV Data Into NDB”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_clear_apply_status
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="reset-replica.html" title="15.4.2.3 RESET REPLICA Statement">
Section 15.4.2.3, “RESET REPLICA Statement”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_conflict_role
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-replication-conflict-resolution.html" title="25.7.12 NDB Cluster Replication Conflict Resolution">
Section 25.7.12, “NDB Cluster Replication Conflict Resolution”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_data_node_neighbour
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="create-table-ndb-comment-options.html" title="15.1.20.12 Setting NDB Comment Options">
Section 15.1.20.12, “Setting NDB Comment Options”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_dbg_check_shares
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_default_column_format
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_deferred_constraints
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_distribution
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_eventbuffer_free_percent
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-logs-event-buffer.html" title="25.6.2.3 Event Buffer Reporting in the Cluster Log">
Section 25.6.2.3, “Event Buffer Reporting in the Cluster Log”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_eventbuffer_max_alloc
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-logs-event-buffer.html" title="25.6.2.3 Event Buffer Reporting in the Cluster Log">
Section 25.6.2.3, “Event Buffer Reporting in the Cluster Log”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_extra_logging
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_force_send
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_fully_replicated
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_index_stat_enable
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_index_stat_option
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_join_pushdown
</h3>
<dl>
<dt>
<a class="xref" href="explain-output.html" title="10.8.2 EXPLAIN Output Format">
Section 10.8.2, “EXPLAIN Output Format”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_log_apply_status
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-replication-failover.html" title="25.7.8 Implementing Failover with NDB Cluster Replication">
Section 25.7.8, “Implementing Failover with NDB Cluster Replication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-replication-multi-source.html" title="25.7.10 NDB Cluster Replication: Bidirectional and Circular Replication">
Section 25.7.10, “NDB Cluster Replication: Bidirectional and Circular Replication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_log_bin
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_log_binlog_index
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_log_cache_size
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-what-is-new.html" title="25.2.4 What is New in MySQL NDB Cluster 8.4">
Section 25.2.4, “What is New in MySQL NDB Cluster 8.4”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_log_empty_epochs
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_log_empty_update
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_log_exclusive_reads
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-program-options-mysqld" title="25.4.3.9.1 MySQL Server Options for NDB Cluster">
Section 25.4.3.9.1, “MySQL Server Options for NDB Cluster”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-replication-conflict-resolution.html" title="25.7.12 NDB Cluster Replication Conflict Resolution">
Section 25.7.12, “NDB Cluster Replication Conflict Resolution”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_log_orig
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_log_transaction_compression
</h3>
<dl>
<dt>
<a class="xref" href="binary-log-transaction-compression.html" title="7.4.4.5 Binary Log Transaction Compression">
Section 7.4.4.5, “Binary Log Transaction Compression”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-binary-log.html" title="19.1.6.4 Binary Logging Options and Variables">
Section 19.1.6.4, “Binary Logging Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_log_transaction_compression_level_zstd
</h3>
<dl>
<dt>
<a class="xref" href="binary-log-transaction-compression.html" title="7.4.4.5 Binary Log Transaction Compression">
Section 7.4.4.5, “Binary Log Transaction Compression”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-binary-log.html" title="19.1.6.4 Binary Logging Options and Variables">
Section 19.1.6.4, “Binary Logging Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_log_transaction_id
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_metadata_check
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-programs-ndb-restore.html" title="25.5.23 ndb_restore — Restore an NDB Cluster Backup">
Section 25.5.23, “ndb_restore — Restore an NDB Cluster Backup”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-ndb-cluster-tables.html" title="29.12.12 Performance Schema NDB Cluster Tables">
Section 29.12.12, “Performance Schema NDB Cluster Tables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_metadata_check_interval
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-ndb-cluster-tables.html" title="29.12.12 Performance Schema NDB Cluster Tables">
Section 29.12.12, “Performance Schema NDB Cluster Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-what-is-new.html" title="25.2.4 What is New in MySQL NDB Cluster 8.4">
Section 25.2.4, “What is New in MySQL NDB Cluster 8.4”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_metadata_sync
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-ndb-cluster-tables.html" title="29.12.12 Performance Schema NDB Cluster Tables">
Section 29.12.12, “Performance Schema NDB Cluster Tables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_optimized_node_selection
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-tcp-definition.html" title="25.4.3.10 NDB Cluster TCP/IP Connections">
Section 25.4.3.10, “NDB Cluster TCP/IP Connections”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-log-statistics.html" title="25.6.3.3 Using CLUSTERLOG STATISTICS in the NDB Cluster Management Client">
Section 25.6.3.3, “Using CLUSTERLOG STATISTICS in the NDB Cluster Management Client”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_read_backup
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="create-table-ndb-comment-options.html" title="15.1.20.12 Setting NDB Comment Options">
Section 15.1.20.12, “Setting NDB Comment Options”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_recv_thread_activation_threshold
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_recv_thread_cpu_mask
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_replica_batch_size
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_replica_blob_write_batch_bytes
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_report_thresh_binlog_epoch_slip
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-logs-event-buffer.html" title="25.6.2.3 Event Buffer Reporting in the Cluster Log">
Section 25.6.2.3, “Event Buffer Reporting in the Cluster Log”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_report_thresh_binlog_mem_usage
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-logs-event-buffer.html" title="25.6.2.3 Event Buffer Reporting in the Cluster Log">
Section 25.6.2.3, “Event Buffer Reporting in the Cluster Log”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_row_checksum
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_schema_dist_lock_wait_timeout
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_schema_dist_timeout
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_schema_dist_upgrade_allowed
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_show_foreign_key_mock_tables
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_slave_conflict_role
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_table_no_logging
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="create-table-ndb-comment-options.html" title="15.1.20.12 Setting NDB Comment Options">
Section 15.1.20.12, “Setting NDB Comment Options”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_table_temporary
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_use_copying_alter_table
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_use_exact_count
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_use_transactions
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-importing-data.html" title="25.6.9 Importing Data Into MySQL Cluster">
Section 25.6.9, “Importing Data Into MySQL Cluster”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_version
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndb_version_string
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndbinfo_database
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndbinfo_max_bytes
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndbinfo_max_rows
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndbinfo_offline
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndbinfo_show_hidden
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-ndbinfo.html" title="25.6.17 ndbinfo: The NDB Cluster Information Database">
Section 25.6.17, “ndbinfo: The NDB Cluster Information Database”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-ndbinfo-cluster-operations.html" title="25.6.17.8 The ndbinfo cluster_operations Table">
Section 25.6.17.8, “The ndbinfo cluster_operations Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-ndbinfo-cluster-transactions.html" title="25.6.17.9 The ndbinfo cluster_transactions Table">
Section 25.6.17.9, “The ndbinfo cluster_transactions Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-ndbinfo-server-operations.html" title="25.6.17.55 The ndbinfo server_operations Table">
Section 25.6.17.55, “The ndbinfo server_operations Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-ndbinfo-server-transactions.html" title="25.6.17.56 The ndbinfo server_transactions Table">
Section 25.6.17.56, “The ndbinfo server_transactions Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndbinfo_table_prefix
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ndbinfo_version
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
net_buffer_length
</h3>
<dl>
<dt>
<a class="xref" href="memory-use.html" title="10.12.3.1 How MySQL Uses Memory">
Section 10.12.3.1, “How MySQL Uses Memory”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysqldump.html" title="6.5.4 mysqldump — A Database Backup Program">
Section 6.5.4, “mysqldump — A Database Backup Program”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
net_read_timeout
</h3>
<dl>
<dt>
<a class="xref" href="error-lost-connection.html" title="B.3.2.3 Lost connection to MySQL server">
Section B.3.2.3, “Lost connection to MySQL server”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
net_retry_count
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
net_write_timeout
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ngram_token_size
</h3>
<dl>
<dt>
<a class="xref" href="fulltext-boolean.html" title="14.9.2 Boolean Full-Text Searches">
Section 14.9.2, “Boolean Full-Text Searches”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="fulltext-fine-tuning.html" title="14.9.6 Fine-Tuning MySQL Full-Text Search">
Section 14.9.6, “Fine-Tuning MySQL Full-Text Search”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="fulltext-stopwords.html" title="14.9.4 Full-Text Stopwords">
Section 14.9.4, “Full-Text Stopwords”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="fulltext-natural-language.html" title="14.9.1 Natural Language Full-Text Searches">
Section 14.9.1, “Natural Language Full-Text Searches”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="fulltext-search-ngram.html" title="14.9.8 ngram Full-Text Parser">
Section 14.9.8, “ngram Full-Text Parser”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<a name="sysvar-index-O">
</a>
<h3 class="title">
O
</h3>
<p>
[
<a class="link" href="dynindex-sysvar.html#sysvar-index-top">
index top
</a>
]
</p>
<dl>
<dt>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
offline_mode
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-responses-failure-exit.html" title="20.7.7.4 Exit Action">
Section 20.7.7.4, “Exit Action”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-server-states.html" title="20.4.2 Group Replication Server States">
Section 20.4.2, “Group Replication Server States”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="privileges-provided.html" title="8.2.2 Privileges Provided by MySQL">
Section 8.2.2, “Privileges Provided by MySQL”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
old_alter_table
</h3>
<dl>
<dt>
<a class="xref" href="alter-table.html" title="15.1.9 ALTER TABLE Statement">
Section 15.1.9, “ALTER TABLE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-online-ddl.html" title="17.12 InnoDB and Online DDL">
Section 17.12, “InnoDB and Online DDL”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="partitioning-management-range-list.html" title="26.3.1 Management of RANGE and LIST Partitions">
Section 26.3.1, “Management of RANGE and LIST Partitions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-online-ddl-operations.html" title="17.12.1 Online DDL Operations">
Section 17.12.1, “Online DDL Operations”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-online-ddl-performance.html" title="17.12.2 Online DDL Performance and Concurrency">
Section 17.12.2, “Online DDL Performance and Concurrency”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="optimize-table.html" title="15.7.3.4 OPTIMIZE TABLE Statement">
Section 15.7.3.4, “OPTIMIZE TABLE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-online-ddl-single-multi.html" title="17.12.6 Simplifying DDL Statements with Online DDL">
Section 17.12.6, “Simplifying DDL Statements with Online DDL”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
open_files_limit
</h3>
<dl>
<dt>
<a class="xref" href="connection-interfaces.html" title="7.1.12.1 Connection Interfaces">
Section 7.1.12.1, “Connection Interfaces”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="not-enough-file-handles.html" title="B.3.2.16 File Not Found and Similar Errors">
Section B.3.2.16, “File Not Found and Similar Errors”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="hash-joins.html" title="10.2.1.4 Hash Join Optimization">
Section 10.2.1.4, “Hash Join Optimization”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="table-cache.html" title="10.4.3.1 How MySQL Opens and Closes Tables">
Section 10.4.3.1, “How MySQL Opens and Closes Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="using-systemd.html" title="2.5.9 Managing MySQL Server with systemd">
Section 2.5.9, “Managing MySQL Server with systemd”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="partitioning-limitations.html" title="26.6 Restrictions and Limitations on Partitioning">
Section 26.6, “Restrictions and Limitations on Partitioning”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="log-destinations.html" title="7.4.1 Selecting General Query Log and Slow Query Log Output Destinations">
Section 7.4.1, “Selecting General Query Log and Slow Query Log Output Destinations”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
optimizer_prune_level
</h3>
<dl>
<dt>
<a class="xref" href="controlling-query-plan-evaluation.html" title="10.9.1 Controlling Query Plan Evaluation">
Section 10.9.1, “Controlling Query Plan Evaluation”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="optimizer-hints.html" title="10.9.3 Optimizer Hints">
Section 10.9.3, “Optimizer Hints”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="semijoins-antijoins.html" title="10.2.2.1 Optimizing IN and EXISTS Subquery Predicates with Semijoin and Antijoin Transformations">
Section 10.2.2.1, “Optimizing IN and EXISTS Subquery Predicates with Semijoin and Antijoin
Transformations”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
optimizer_search_depth
</h3>
<dl>
<dt>
<a class="xref" href="controlling-query-plan-evaluation.html" title="10.9.1 Controlling Query Plan Evaluation">
Section 10.9.1, “Controlling Query Plan Evaluation”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
optimizer_switch
</h3>
<dl>
<dt>
<a class="xref" href="bnl-bka-optimization.html" title="10.2.1.12 Block Nested-Loop and Batched Key Access Joins">
Section 10.2.1.12, “Block Nested-Loop and Batched Key Access Joins”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="condition-filtering.html" title="10.2.1.13 Condition Filtering">
Section 10.2.1.13, “Condition Filtering”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="correlated-subqueries.html" title="15.2.15.7 Correlated Subqueries">
Section 15.2.15.7, “Correlated Subqueries”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="derived-condition-pushdown-optimization.html" title="10.2.2.5 Derived Condition Pushdown Optimization">
Section 10.2.2.5, “Derived Condition Pushdown Optimization”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="engine-condition-pushdown-optimization.html" title="10.2.1.5 Engine Condition Pushdown Optimization">
Section 10.2.1.5, “Engine Condition Pushdown Optimization”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="index-condition-pushdown-optimization.html" title="10.2.1.6 Index Condition Pushdown Optimization">
Section 10.2.1.6, “Index Condition Pushdown Optimization”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="index-merge-optimization.html" title="10.2.1.3 Index Merge Optimization">
Section 10.2.1.3, “Index Merge Optimization”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="invisible-indexes.html" title="10.3.12 Invisible Indexes">
Section 10.3.12, “Invisible Indexes”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="limit-optimization.html" title="10.2.1.19 LIMIT Query Optimization">
Section 10.2.1.19, “LIMIT Query Optimization”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mrr-optimization.html" title="10.2.1.11 Multi-Range Read Optimization">
Section 10.2.1.11, “Multi-Range Read Optimization”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="optimizer-hints.html" title="10.9.3 Optimizer Hints">
Section 10.9.3, “Optimizer Hints”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="optimizer-statistics.html" title="10.9.6 Optimizer Statistics">
Section 10.9.6, “Optimizer Statistics”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="derived-table-optimization.html" title="10.2.2.4 Optimizing Derived Tables, View References, and Common Table Expressions with Merging or Materialization">
Section 10.2.2.4, “Optimizing Derived Tables, View References, and Common Table Expressions
with Merging or Materialization”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="semijoins-antijoins.html" title="10.2.2.1 Optimizing IN and EXISTS Subquery Predicates with Semijoin and Antijoin Transformations">
Section 10.2.2.1, “Optimizing IN and EXISTS Subquery Predicates with Semijoin and Antijoin
Transformations”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="subquery-materialization.html" title="10.2.2.2 Optimizing Subqueries with Materialization">
Section 10.2.2.2, “Optimizing Subqueries with Materialization”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="subquery-optimization-with-exists.html" title="10.2.2.3 Optimizing Subqueries with the EXISTS Strategy">
Section 10.2.2.3, “Optimizing Subqueries with the EXISTS Strategy”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="range-optimization.html" title="10.2.1.2 Range Optimization">
Section 10.2.1.2, “Range Optimization”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="switchable-optimizations.html" title="10.9.2 Switchable Optimizations">
Section 10.9.2, “Switchable Optimizations”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="sys-list-add.html" title="30.4.5.7 The list_add() Function">
Section 30.4.5.7, “The list_add() Function”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="update.html" title="15.2.17 UPDATE Statement">
Section 15.2.17, “UPDATE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="index-extensions.html" title="10.3.10 Use of Index Extensions">
Section 10.3.10, “Use of Index Extensions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="view-algorithms.html" title="27.5.2 View Processing Algorithms">
Section 27.5.2, “View Processing Algorithms”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
optimizer_trace
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="system-variables-controlling-tracing.html" title="10.15.2 System Variables Controlling Tracing">
Section 10.15.2, “System Variables Controlling Tracing”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-optimizer-trace-table.html" title="28.3.19 The INFORMATION_SCHEMA OPTIMIZER_TRACE Table">
Section 28.3.19, “The INFORMATION_SCHEMA OPTIMIZER_TRACE Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="optimizer-tracing-typical-usage.html" title="10.15.1 Typical Usage">
Section 10.15.1, “Typical Usage”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
optimizer_trace_features
</h3>
<dl>
<dt>
<a class="xref" href="optimizer-features-to-trace.html" title="10.15.10 Selecting Optimizer Features to Trace">
Section 10.15.10, “Selecting Optimizer Features to Trace”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="system-variables-controlling-tracing.html" title="10.15.2 System Variables Controlling Tracing">
Section 10.15.2, “System Variables Controlling Tracing”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
optimizer_trace_limit
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="system-variables-controlling-tracing.html" title="10.15.2 System Variables Controlling Tracing">
Section 10.15.2, “System Variables Controlling Tracing”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="tuning-trace-purging.html" title="10.15.4 Tuning Trace Purging">
Section 10.15.4, “Tuning Trace Purging”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
optimizer_trace_max_mem_size
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="system-variables-controlling-tracing.html" title="10.15.2 System Variables Controlling Tracing">
Section 10.15.2, “System Variables Controlling Tracing”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-optimizer-trace-table.html" title="28.3.19 The INFORMATION_SCHEMA OPTIMIZER_TRACE Table">
Section 28.3.19, “The INFORMATION_SCHEMA OPTIMIZER_TRACE Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="tracing-memory-usage.html" title="10.15.5 Tracing Memory Usage">
Section 10.15.5, “Tracing Memory Usage”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
optimizer_trace_offset
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="system-variables-controlling-tracing.html" title="10.15.2 System Variables Controlling Tracing">
Section 10.15.2, “System Variables Controlling Tracing”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="tuning-trace-purging.html" title="10.15.4 Tuning Trace Purging">
Section 10.15.4, “Tuning Trace Purging”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
original_commit_timestamp
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-binary-log.html" title="19.1.6.4 Binary Logging Options and Variables">
Section 19.1.6.4, “Binary Logging Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-privilege-checks-account.html" title="19.3.3.1 Privileges For The Replication PRIVILEGE_CHECKS_USER Account">
Section 19.3.3.1, “Privileges For The Replication PRIVILEGE_CHECKS_USER Account”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
original_server_version
</h3>
<dl>
<dt>
<a class="xref" href="mysqlbinlog.html" title="6.6.9 mysqlbinlog — Utility for Processing Binary Log Files">
Section 6.6.9, “mysqlbinlog — Utility for Processing Binary Log Files”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-privilege-checks-account.html" title="19.3.3.1 Privileges For The Replication PRIVILEGE_CHECKS_USER Account">
Section 19.3.3.1, “Privileges For The Replication PRIVILEGE_CHECKS_USER Account”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-compatibility.html" title="19.5.2 Replication Compatibility Between MySQL Versions">
Section 19.5.2, “Replication Compatibility Between MySQL Versions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-source.html" title="19.1.6.2 Replication Source Options and Variables">
Section 19.1.6.2, “Replication Source Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<a name="sysvar-index-P">
</a>
<h3 class="title">
P
</h3>
<p>
[
<a class="link" href="dynindex-sysvar.html#sysvar-index-top">
index top
</a>
]
</p>
<dl>
<dt>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
parser_max_mem_size
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
partial_revokes
</h3>
<dl>
<dt>
<a class="xref" href="account-categories.html" title="8.2.11 Account Categories">
Section 8.2.11, “Account Categories”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="grant.html" title="15.7.1.6 GRANT Statement">
Section 15.7.1.6, “GRANT Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="partial-revokes.html" title="8.2.12 Privilege Restriction Using Partial Revokes">
Section 8.2.12, “Privilege Restriction Using Partial Revokes”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="account-names.html" title="8.2.4 Specifying Account Names">
Section 8.2.4, “Specifying Account Names”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
password_history
</h3>
<dl>
<dt>
<a class="xref" href="alter-user.html" title="15.7.1.1 ALTER USER Statement">
Section 15.7.1.1, “ALTER USER Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="create-user.html" title="15.7.1.3 CREATE USER Statement">
Section 15.7.1.3, “CREATE USER Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="password-management.html" title="8.2.15 Password Management">
Section 8.2.15, “Password Management”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
password_require_current
</h3>
<dl>
<dt>
<a class="xref" href="alter-user.html" title="15.7.1.1 ALTER USER Statement">
Section 15.7.1.1, “ALTER USER Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="create-user.html" title="15.7.1.3 CREATE USER Statement">
Section 15.7.1.3, “CREATE USER Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="password-management.html" title="8.2.15 Password Management">
Section 8.2.15, “Password Management”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
password_reuse_interval
</h3>
<dl>
<dt>
<a class="xref" href="alter-user.html" title="15.7.1.1 ALTER USER Statement">
Section 15.7.1.1, “ALTER USER Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="create-user.html" title="15.7.1.3 CREATE USER Statement">
Section 15.7.1.3, “CREATE USER Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="password-management.html" title="8.2.15 Password Management">
Section 8.2.15, “Password Management”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
performance_schema
</h3>
<dl>
<dt>
<a class="xref" href="performance-schema-quick-start.html" title="29.1 Performance Schema Quick Start">
Section 29.1, “Performance Schema Quick Start”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-startup-configuration.html" title="29.3 Performance Schema Startup Configuration">
Section 29.3, “Performance Schema Startup Configuration”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-processlist-table.html" title="29.12.22.7 The processlist Table">
Section 29.12.22.7, “The processlist Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
performance_schema_accounts_size
</h3>
<dl>
<dt>
<a class="xref" href="performance-schema-status-variable-tables.html" title="29.12.15 Performance Schema Status Variable Tables">
Section 29.12.15, “Performance Schema Status Variable Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-status-variable-summary-tables.html" title="29.12.20.12 Status Variable Summary Tables">
Section 29.12.20.12, “Status Variable Summary Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-accounts-table.html" title="29.12.8.1 The accounts Table">
Section 29.12.8.1, “The accounts Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
performance_schema_digests_size
</h3>
<dl>
<dt>
<a class="xref" href="performance-schema-statement-digests.html" title="29.10 Performance Schema Statement Digests and Sampling">
Section 29.10, “Performance Schema Statement Digests and Sampling”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-status-variables.html" title="29.16 Performance Schema Status Variables">
Section 29.16, “Performance Schema Status Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-statement-summary-tables.html" title="29.12.20.3 Statement Summary Tables">
Section 29.12.20.3, “Statement Summary Tables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
performance_schema_error_size
</h3>
<dl>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
performance_schema_events_stages_history_long_size
</h3>
<dl>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-events-stages-history-long-table.html" title="29.12.5.3 The events_stages_history_long Table">
Section 29.12.5.3, “The events_stages_history_long Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
performance_schema_events_stages_history_size
</h3>
<dl>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-events-stages-history-table.html" title="29.12.5.2 The events_stages_history Table">
Section 29.12.5.2, “The events_stages_history Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
performance_schema_events_statements_history_long_size
</h3>
<dl>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-events-statements-history-long-table.html" title="29.12.6.3 The events_statements_history_long Table">
Section 29.12.6.3, “The events_statements_history_long Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
performance_schema_events_statements_history_size
</h3>
<dl>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-events-statements-history-table.html" title="29.12.6.2 The events_statements_history Table">
Section 29.12.6.2, “The events_statements_history Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
performance_schema_events_transactions_history_long_size
</h3>
<dl>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-events-transactions-history-long-table.html" title="29.12.7.3 The events_transactions_history_long Table">
Section 29.12.7.3, “The events_transactions_history_long Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
performance_schema_events_transactions_history_size
</h3>
<dl>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-events-transactions-history-table.html" title="29.12.7.2 The events_transactions_history Table">
Section 29.12.7.2, “The events_transactions_history Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
performance_schema_events_waits_history_long_size
</h3>
<dl>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-table-descriptions.html" title="29.12 Performance Schema Table Descriptions">
Section 29.12, “Performance Schema Table Descriptions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="show-engine.html" title="15.7.7.16 SHOW ENGINE Statement">
Section 15.7.7.16, “SHOW ENGINE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-events-waits-history-long-table.html" title="29.12.4.3 The events_waits_history_long Table">
Section 29.12.4.3, “The events_waits_history_long Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
performance_schema_events_waits_history_size
</h3>
<dl>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-table-descriptions.html" title="29.12 Performance Schema Table Descriptions">
Section 29.12, “Performance Schema Table Descriptions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="show-engine.html" title="15.7.7.16 SHOW ENGINE Statement">
Section 15.7.7.16, “SHOW ENGINE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-events-waits-history-table.html" title="29.12.4.2 The events_waits_history Table">
Section 29.12.4.2, “The events_waits_history Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
performance_schema_hosts_size
</h3>
<dl>
<dt>
<a class="xref" href="performance-schema-status-variable-tables.html" title="29.12.15 Performance Schema Status Variable Tables">
Section 29.12.15, “Performance Schema Status Variable Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-status-variable-summary-tables.html" title="29.12.20.12 Status Variable Summary Tables">
Section 29.12.20.12, “Status Variable Summary Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-hosts-table.html" title="29.12.8.2 The hosts Table">
Section 29.12.8.2, “The hosts Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
performance_schema_max_cond_classes
</h3>
<dl>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
performance_schema_max_cond_instances
</h3>
<dl>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
performance_schema_max_digest_length
</h3>
<dl>
<dt>
<a class="xref" href="performance-schema-statement-digests.html" title="29.10 Performance Schema Statement Digests and Sampling">
Section 29.10, “Performance Schema Statement Digests and Sampling”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-events-statements-current-table.html" title="29.12.6.1 The events_statements_current Table">
Section 29.12.6.1, “The events_statements_current Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
performance_schema_max_digest_sample_age
</h3>
<dl>
<dt>
<a class="xref" href="performance-schema-statement-digests.html" title="29.10 Performance Schema Statement Digests and Sampling">
Section 29.10, “Performance Schema Statement Digests and Sampling”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
performance_schema_max_file_classes
</h3>
<dl>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
performance_schema_max_file_handles
</h3>
<dl>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
performance_schema_max_file_instances
</h3>
<dl>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
performance_schema_max_index_stat
</h3>
<dl>
<dt>
<a class="xref" href="performance-schema-status-variables.html" title="29.16 Performance Schema Status Variables">
Section 29.16, “Performance Schema Status Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
performance_schema_max_memory_classes
</h3>
<dl>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
performance_schema_max_metadata_locks
</h3>
<dl>
<dt>
<a class="xref" href="performance-schema-status-variables.html" title="29.16 Performance Schema Status Variables">
Section 29.16, “Performance Schema Status Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-metadata-locks-table.html" title="29.12.13.3 The metadata_locks Table">
Section 29.12.13.3, “The metadata_locks Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
performance_schema_max_meter_classes
</h3>
<dl>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="telemetry-metrics-meters.html" title="35.4.2 Server Meters">
Section 35.4.2, “Server Meters”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
performance_schema_max_metric_classes
</h3>
<dl>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="telemetry-metrics-meter-metrics.html" title="35.4.3 Server Metrics">
Section 35.4.3, “Server Metrics”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
performance_schema_max_mutex_classes
</h3>
<dl>
<dt>
<a class="xref" href="performance-schema-status-monitoring.html" title="29.7 Performance Schema Status Monitoring">
Section 29.7, “Performance Schema Status Monitoring”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
performance_schema_max_mutex_instances
</h3>
<dl>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
performance_schema_max_prepared_statements_instances
</h3>
<dl>
<dt>
<a class="xref" href="performance-schema-status-variables.html" title="29.16 Performance Schema Status Variables">
Section 29.16, “Performance Schema Status Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-prepared-statements-instances-table.html" title="29.12.6.4 The prepared_statements_instances Table">
Section 29.12.6.4, “The prepared_statements_instances Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
performance_schema_max_program_instances
</h3>
<dl>
<dt>
<a class="xref" href="performance-schema-status-variables.html" title="29.16 Performance Schema Status Variables">
Section 29.16, “Performance Schema Status Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
performance_schema_max_rwlock_classes
</h3>
<dl>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
performance_schema_max_rwlock_instances
</h3>
<dl>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
performance_schema_max_socket_classes
</h3>
<dl>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
performance_schema_max_socket_instances
</h3>
<dl>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
performance_schema_max_sql_text_length
</h3>
<dl>
<dt>
<a class="xref" href="performance-schema-statement-digests.html" title="29.10 Performance Schema Statement Digests and Sampling">
Section 29.10, “Performance Schema Statement Digests and Sampling”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-statement-summary-tables.html" title="29.12.20.3 Statement Summary Tables">
Section 29.12.20.3, “Statement Summary Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-events-statements-current-table.html" title="29.12.6.1 The events_statements_current Table">
Section 29.12.6.1, “The events_statements_current Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
performance_schema_max_stage_classes
</h3>
<dl>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-processlist-table.html" title="29.12.22.7 The processlist Table">
Section 29.12.22.7, “The processlist Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
performance_schema_max_statement_classes
</h3>
<dl>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
performance_schema_max_statement_stack
</h3>
<dl>
<dt>
<a class="xref" href="performance-schema-status-variables.html" title="29.16 Performance Schema Status Variables">
Section 29.16, “Performance Schema Status Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
performance_schema_max_table_handles
</h3>
<dl>
<dt>
<a class="xref" href="performance-schema-status-variables.html" title="29.16 Performance Schema Status Variables">
Section 29.16, “Performance Schema Status Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-table-handles-table.html" title="29.12.13.4 The table_handles Table">
Section 29.12.13.4, “The table_handles Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
performance_schema_max_table_instances
</h3>
<dl>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
performance_schema_max_table_lock_stat
</h3>
<dl>
<dt>
<a class="xref" href="performance-schema-status-variables.html" title="29.16 Performance Schema Status Variables">
Section 29.16, “Performance Schema Status Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
performance_schema_max_thread_classes
</h3>
<dl>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-processlist-table.html" title="29.12.22.7 The processlist Table">
Section 29.12.22.7, “The processlist Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
performance_schema_max_thread_instances
</h3>
<dl>
<dt>
<a class="xref" href="performance-schema-functions.html" title="14.21 Performance Schema Functions">
Section 14.21, “Performance Schema Functions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-status-variable-tables.html" title="29.12.15 Performance Schema Status Variable Tables">
Section 29.12.15, “Performance Schema Status Variable Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-status-variables.html" title="29.16 Performance Schema Status Variables">
Section 29.16, “Performance Schema Status Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="show-engine.html" title="15.7.7.16 SHOW ENGINE Statement">
Section 15.7.7.16, “SHOW ENGINE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-processlist-table.html" title="29.12.22.7 The processlist Table">
Section 29.12.22.7, “The processlist Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
performance_schema_session_connect_attrs_size
</h3>
<dl>
<dt>
<a class="xref" href="performance-schema-connection-attribute-tables.html" title="29.12.9 Performance Schema Connection Attribute Tables">
Section 29.12.9, “Performance Schema Connection Attribute Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-status-variables.html" title="29.16 Performance Schema Status Variables">
Section 29.16, “Performance Schema Status Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
performance_schema_setup_actors_size
</h3>
<dl>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-setup-actors-table.html" title="29.12.2.1 The setup_actors Table">
Section 29.12.2.1, “The setup_actors Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
performance_schema_setup_objects_size
</h3>
<dl>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-setup-objects-table.html" title="29.12.2.4 The setup_objects Table">
Section 29.12.2.4, “The setup_objects Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
performance_schema_show_processlist
</h3>
<dl>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-processlist-table.html" title="29.12.22.7 The processlist Table">
Section 29.12.22.7, “The processlist Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
performance_schema_users_size
</h3>
<dl>
<dt>
<a class="xref" href="performance-schema-status-variable-tables.html" title="29.12.15 Performance Schema Status Variable Tables">
Section 29.12.15, “Performance Schema Status Variable Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-system-variables.html" title="29.15 Performance Schema System Variables">
Section 29.15, “Performance Schema System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-status-variable-summary-tables.html" title="29.12.20.12 Status Variable Summary Tables">
Section 29.12.20.12, “Status Variable Summary Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-users-table.html" title="29.12.8.3 The users Table">
Section 29.12.8.3, “The users Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
persist_only_admin_x
</h3>
<dl>
<dt>
<a class="xref" href="nonpersistible-system-variables.html" title="7.1.9.4 Nonpersistible and Persist-Restricted System Variables">
Section 7.1.9.4, “Nonpersistible and Persist-Restricted System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="system-variable-privileges.html" title="7.1.9.1 System Variable Privileges">
Section 7.1.9.1, “System Variable Privileges”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
persist_sensitive_variables_in_plaintext
</h3>
<dl>
<dt>
<a class="xref" href="persisted-system-variables.html" title="7.1.9.3 Persisted System Variables">
Section 7.1.9.3, “Persisted System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
persisted_globals_load
</h3>
<dl>
<dt>
<a class="xref" href="nonpersistible-system-variables.html" title="7.1.9.4 Nonpersistible and Persist-Restricted System Variables">
Section 7.1.9.4, “Nonpersistible and Persist-Restricted System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-variables-info-table.html" title="29.12.14.2 Performance Schema variables_info Table">
Section 29.12.14.2, “Performance Schema variables_info Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="persisted-system-variables.html" title="7.1.9.3 Persisted System Variables">
Section 7.1.9.3, “Persisted System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="reset-persist.html" title="15.7.8.7 RESET PERSIST Statement">
Section 15.7.8.7, “RESET PERSIST Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="option-files.html" title="6.2.2.2 Using Option Files">
Section 6.2.2.2, “Using Option Files”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
pid
</h3>
<dl>
<dt>
<a class="xref" href="innodb-read-only-instance.html" title="17.8.2 Configuring InnoDB for Read-Only Operation">
Section 17.8.2, “Configuring InnoDB for Read-Only Operation”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
pid_file
</h3>
<dl>
<dt>
<a class="xref" href="macos-installation-launchd.html" title="2.4.3 Installing and Using the MySQL Launch Daemon">
Section 2.4.3, “Installing and Using the MySQL Launch Daemon”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
plugin_dir
</h3>
<dl>
<dt>
<a class="xref" href="password-security-admin.html" title="8.1.2.2 Administrator Guidelines for Password Security">
Section 8.1.2.2, “Administrator Guidelines for Password Security”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="connection-control-installation.html" title="8.4.2.1 Connection-Control Plugin Installation">
Section 8.4.2.1, “Connection-Control Plugin Installation”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="create-function-loadable.html" title="15.7.4.1 CREATE FUNCTION Statement for Loadable Functions">
Section 15.7.4.1, “CREATE FUNCTION Statement for Loadable Functions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="keyring-functions-general-purpose.html" title="8.4.4.12 General-Purpose Keyring Key-Management Functions">
Section 8.4.4.12, “General-Purpose Keyring Key-Management Functions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="install-component.html" title="15.7.4.3 INSTALL COMPONENT Statement">
Section 15.7.4.3, “INSTALL COMPONENT Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="install-plugin.html" title="15.7.4.4 INSTALL PLUGIN Statement">
Section 15.7.4.4, “INSTALL PLUGIN Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="plugin-loading.html" title="7.6.1 Installing and Uninstalling Plugins">
Section 7.6.1, “Installing and Uninstalling Plugins”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="macos-installation-launchd.html" title="2.4.3 Installing and Using the MySQL Launch Daemon">
Section 2.4.3, “Installing and Using the MySQL Launch Daemon”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="linux-installation-rpm.html" title="2.5.4 Installing MySQL on Linux Using RPM Packages from Oracle">
Section 2.5.4, “Installing MySQL on Linux Using RPM Packages from Oracle”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="ddl-rewriter-installation.html" title="7.6.5.1 Installing or Uninstalling ddl_rewriter">
Section 7.6.5.1, “Installing or Uninstalling ddl_rewriter”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="audit-log-installation.html" title="8.4.5.2 Installing or Uninstalling MySQL Enterprise Audit">
Section 8.4.5.2, “Installing or Uninstalling MySQL Enterprise Audit”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="version-tokens-installation.html" title="7.6.6.2 Installing or Uninstalling Version Tokens">
Section 7.6.6.2, “Installing or Uninstalling Version Tokens”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-semisync-installation.html" title="19.4.10.1 Installing Semisynchronous Replication">
Section 19.4.10.1, “Installing Semisynchronous Replication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="clone-plugin-installation.html" title="7.6.7.1 Installing the Clone Plugin">
Section 7.6.7.1, “Installing the Clone Plugin”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="kerberos-pluggable-authentication.html" title="8.4.1.8 Kerberos Pluggable Authentication">
Section 8.4.1.8, “Kerberos Pluggable Authentication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="keyring-options.html" title="8.4.4.15 Keyring Command Options">
Section 8.4.4.15, “Keyring Command Options”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="keyring-component-installation.html" title="8.4.4.2 Keyring Component Installation">
Section 8.4.4.2, “Keyring Component Installation”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="keyring-plugin-installation.html" title="8.4.4.3 Keyring Plugin Installation">
Section 8.4.4.3, “Keyring Plugin Installation”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="ldap-pluggable-authentication.html" title="8.4.1.7 LDAP Pluggable Authentication">
Section 8.4.1.7, “LDAP Pluggable Authentication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="security-against-attack.html" title="8.1.3 Making MySQL Secure Against Attackers">
Section 8.1.3, “Making MySQL Secure Against Attackers”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="keyring-key-migration.html" title="8.4.4.11 Migrating Keys Between Keyring Keystores">
Section 8.4.4.11, “Migrating Keys Between Keyring Keystores”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="data-masking-plugin-installation.html" title="8.5.3.1 MySQL Enterprise Data Masking and De-Identification Plugin Installation">
Section 8.5.3.1, “MySQL Enterprise Data Masking and De-Identification Plugin Installation”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-migrate-keyring.html" title="6.6.8 mysql_migrate_keyring — Keyring Key Migration Utility">
Section 6.6.8, “mysql_migrate_keyring — Keyring Key Migration Utility”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="no-login-pluggable-authentication.html" title="8.4.1.9 No-Login Pluggable Authentication">
Section 8.4.1.9, “No-Login Pluggable Authentication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="pam-pluggable-authentication.html" title="8.4.1.5 PAM Pluggable Authentication">
Section 8.4.1.5, “PAM Pluggable Authentication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="validate-password-installation.html" title="8.4.3.1 Password Validation Component Installation and Uninstallation">
Section 8.4.3.1, “Password Validation Component Installation and Uninstallation”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="pluggable-authentication.html" title="8.2.17 Pluggable Authentication">
Section 8.2.17, “Pluggable Authentication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="pluggable-storage.html" title="18.11.1 Pluggable Storage Engine Architecture">
Section 18.11.1, “Pluggable Storage Engine Architecture”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-options.html" title="7.1.7 Server Command Options">
Section 7.1.7, “Server Command Options”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="show-plugins.html" title="15.7.7.27 SHOW PLUGINS Statement">
Section 15.7.7.27, “SHOW PLUGINS Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="socket-pluggable-authentication.html" title="8.4.1.10 Socket Peer-Credential Pluggable Authentication">
Section 8.4.1.10, “Socket Peer-Credential Pluggable Authentication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="test-pluggable-authentication.html" title="8.4.1.12 Test Pluggable Authentication">
Section 8.4.1.12, “Test Pluggable Authentication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="audit-api-message-emit.html" title="8.4.6 The Audit Message Component">
Section 8.4.6, “The Audit Message Component”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-plugins-table.html" title="28.3.22 The INFORMATION_SCHEMA PLUGINS Table">
Section 28.3.22, “The INFORMATION_SCHEMA PLUGINS Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="locking-service.html#locking-service-interface" title="7.6.9.1.2 The Locking Service Function Interface">
Section 7.6.9.1.2, “The Locking Service Function Interface”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-user-defined-functions-table.html" title="29.12.22.10 The user_defined_functions Table">
Section 29.12.22.10, “The user_defined_functions Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="thread-pool-installation.html" title="7.6.3.2 Thread Pool Installation">
Section 7.6.3.2, “Thread Pool Installation”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="webauthn-pluggable-authentication.html" title="8.4.1.11 WebAuthn Pluggable Authentication">
Section 8.4.1.11, “WebAuthn Pluggable Authentication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="windows-pluggable-authentication.html" title="8.4.1.6 Windows Pluggable Authentication">
Section 8.4.1.6, “Windows Pluggable Authentication”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
port
</h3>
<dl>
<dt>
<a class="xref" href="can-not-connect-to-server.html" title="B.3.2.2 Can't connect to [local] MySQL server">
Section B.3.2.2, “Can't connect to [local] MySQL server”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="clone.html" title="15.7.5 CLONE Statement">
Section 15.7.5, “CLONE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="clone-plugin-remote.html" title="7.6.7.3 Cloning Remote Data">
Section 7.6.7.3, “Cloning Remote Data”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-configuring-instances.html" title="20.2.1.2 Configuring an Instance for Group Replication">
Section 20.2.1.2, “Configuring an Instance for Group Replication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-distributed-recovery-connections.html" title="20.5.4.1 Connections for Distributed Recovery">
Section 20.5.4.1, “Connections for Distributed Recovery”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-frequently-asked-questions.html" title="20.10 Frequently Asked Questions">
Section 20.10, “Frequently Asked Questions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-shell-tutorial-javascript-shell.html" title="22.3.1 MySQL Shell">
Section 22.3.1, “MySQL Shell”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-shell-tutorial-python-shell.html" title="22.4.1 MySQL Shell">
Section 22.4.1, “MySQL Shell”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-distributed-recovery-securing.html" title="20.6.3 Securing Distributed Recovery Connections">
Section 20.6.3, “Securing Distributed Recovery Connections”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-distributed-recovery-connections.html#group-replication-distributed-recovery-connections-endpoints" title="20.5.4.1.1 Selecting addresses for distributed recovery endpoints">
Section 20.5.4.1.1, “Selecting addresses for distributed recovery endpoints”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="selinux-context-mysqld-tcp-port.html" title="8.7.5.1 Setting the TCP Port Context for mysqld">
Section 8.7.5.1, “Setting the TCP Port Context for mysqld”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-replication-group-members-table.html" title="29.12.11.16 The replication_group_members Table">
Section 29.12.11.16, “The replication_group_members Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="x-plugin-options-system-variables.html" title="22.5.6.2 X Plugin Options and System Variables">
Section 22.5.6.2, “X Plugin Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
preload_buffer_size
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
print_identified_with_as_hex
</h3>
<dl>
<dt>
<a class="xref" href="creating-accounts.html" title="8.2.8 Adding Accounts, Assigning Privileges, and Dropping Accounts">
Section 8.2.8, “Adding Accounts, Assigning Privileges, and Dropping Accounts”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="alter-user.html" title="15.7.1.1 ALTER USER Statement">
Section 15.7.1.1, “ALTER USER Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="create-user.html" title="15.7.1.3 CREATE USER Statement">
Section 15.7.1.3, “CREATE USER Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="show-create-user.html" title="15.7.7.13 SHOW CREATE USER Statement">
Section 15.7.7.13, “SHOW CREATE USER Statement”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
profiling
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="show-profile.html" title="15.7.7.32 SHOW PROFILE Statement">
Section 15.7.7.32, “SHOW PROFILE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-profiling-table.html" title="28.3.24 The INFORMATION_SCHEMA PROFILING Table">
Section 28.3.24, “The INFORMATION_SCHEMA PROFILING Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
profiling_history_size
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="show-profile.html" title="15.7.7.32 SHOW PROFILE Statement">
Section 15.7.7.32, “SHOW PROFILE Statement”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
protocol_compression_algorithms
</h3>
<dl>
<dt>
<a class="xref" href="change-replication-source-to.html" title="15.4.2.2 CHANGE REPLICATION SOURCE TO Statement">
Section 15.4.2.2, “CHANGE REPLICATION SOURCE TO Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="connection-options.html" title="6.2.3 Command Options for Connecting to the Server">
Section 6.2.3, “Command Options for Connecting to the Server”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="connection-compression-control.html" title="6.2.8 Connection Compression Control">
Section 6.2.8, “Connection Compression Control”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="x-plugin-connection-compression.html" title="22.5.5 Connection Compression with X Plugin">
Section 22.5.5, “Connection Compression with X Plugin”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-command-options.html" title="6.5.1.1 mysql Client Options">
Section 6.5.1.1, “mysql Client Options”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysqladmin.html" title="6.5.2 mysqladmin — A MySQL Server Administration Program">
Section 6.5.2, “mysqladmin — A MySQL Server Administration Program”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysqlbinlog.html" title="6.6.9 mysqlbinlog — Utility for Processing Binary Log Files">
Section 6.6.9, “mysqlbinlog — Utility for Processing Binary Log Files”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysqlcheck.html" title="6.5.3 mysqlcheck — A Table Maintenance Program">
Section 6.5.3, “mysqlcheck — A Table Maintenance Program”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysqldump.html" title="6.5.4 mysqldump — A Database Backup Program">
Section 6.5.4, “mysqldump — A Database Backup Program”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysqlimport.html" title="6.5.5 mysqlimport — A Data Import Program">
Section 6.5.5, “mysqlimport — A Data Import Program”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysqlshow.html" title="6.5.6 mysqlshow — Display Database, Table, and Column Information">
Section 6.5.6, “mysqlshow — Display Database, Table, and Column Information”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysqlslap.html" title="6.5.7 mysqlslap — A Load Emulation Client">
Section 6.5.7, “mysqlslap — A Load Emulation Client”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-status-variables.html" title="7.1.10 Server Status Variables">
Section 7.1.10, “Server Status Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
protocol_version
</h3>
<dl>
<dt>
<a class="xref" href="nonpersistible-system-variables.html" title="7.1.9.4 Nonpersistible and Persist-Restricted System Variables">
Section 7.1.9.4, “Nonpersistible and Persist-Restricted System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
proxy_user
</h3>
<dl>
<dt>
<a class="xref" href="proxy-users.html" title="8.2.19 Proxy Users">
Section 8.2.19, “Proxy Users”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
pseudo_replica_mode
</h3>
<dl>
<dt>
<a class="xref" href="mysqlbinlog.html" title="6.6.9 mysqlbinlog — Utility for Processing Binary Log Files">
Section 6.6.9, “mysqlbinlog — Utility for Processing Binary Log Files”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-privilege-checks-account.html" title="19.3.3.1 Privileges For The Replication PRIVILEGE_CHECKS_USER Account">
Section 19.3.3.1, “Privileges For The Replication PRIVILEGE_CHECKS_USER Account”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
pseudo_slave_mode
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
pseudo_thread_id
</h3>
<dl>
<dt>
<a class="xref" href="information-functions.html" title="14.15 Information Functions">
Section 14.15, “Information Functions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log-mixed.html" title="7.4.4.3 Mixed Binary Logging Format">
Section 7.4.4.3, “Mixed Binary Logging Format”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-variables.html" title="19.5.1.39 Replication and Variables">
Section 19.5.1.39, “Replication and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-privilege-checks.html" title="19.3.3 Replication Privilege Checks">
Section 19.3.3, “Replication Privilege Checks”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<a name="sysvar-index-Q">
</a>
<h3 class="title">
Q
</h3>
<p>
[
<a class="link" href="dynindex-sysvar.html#sysvar-index-top">
index top
</a>
]
</p>
<dl>
<dt>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
query_alloc_block_size
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
query_prealloc_size
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<a name="sysvar-index-R">
</a>
<h3 class="title">
R
</h3>
<p>
[
<a class="link" href="dynindex-sysvar.html#sysvar-index-top">
index top
</a>
]
</p>
<dl>
<dt>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
rand_seed
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
range_alloc_block_size
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
range_optimizer_max_mem_size
</h3>
<dl>
<dt>
<a class="xref" href="mysql-tips.html" title="6.5.1.6 mysql Client Tips">
Section 6.5.1.6, “mysql Client Tips”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="range-optimization.html" title="10.2.1.2 Range Optimization">
Section 10.2.1.2, “Range Optimization”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
rbr_exec_mode
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
read_buffer_size
</h3>
<dl>
<dt>
<a class="xref" href="memory-use.html" title="10.12.3.1 How MySQL Uses Memory">
Section 10.12.3.1, “How MySQL Uses Memory”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="repair-table-optimization.html" title="10.6.3 Optimizing REPAIR TABLE Statements">
Section 10.6.3, “Optimizing REPAIR TABLE Statements”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
read_only
</h3>
<dl>
<dt>
<a class="xref" href="account-management-statements.html" title="15.7.1 Account Management Statements">
Section 15.7.1, “Account Management Statements”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="alter-user.html" title="15.7.1.1 ALTER USER Statement">
Section 15.7.1.1, “ALTER USER Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="assigning-passwords.html" title="8.2.14 Assigning Account Passwords">
Section 8.2.14, “Assigning Account Passwords”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-solutions-backups-read-only.html" title="19.4.1.3 Backing Up a Source or Replica by Making It Read Only">
Section 19.4.1.3, “Backing Up a Source or Replica by Making It Read Only”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-member-actions.html" title="20.5.1.5 Configuring Member Actions">
Section 20.5.1.5, “Configuring Member Actions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="create-role.html" title="15.7.1.2 CREATE ROLE Statement">
Section 15.7.1.2, “CREATE ROLE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="create-user.html" title="15.7.1.3 CREATE USER Statement">
Section 15.7.1.3, “CREATE USER Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="drop-role.html" title="15.7.1.4 DROP ROLE Statement">
Section 15.7.1.4, “DROP ROLE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="drop-user.html" title="15.7.1.5 DROP USER Statement">
Section 15.7.1.5, “DROP USER Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="flush.html" title="15.7.8.3 FLUSH Statement">
Section 15.7.8.3, “FLUSH Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-functions-for-member-actions.html" title="14.18.1.5 Functions to Set and Reset Group Replication Member Actions">
Section 14.18.1.5, “Functions to Set and Reset Group Replication Member Actions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="grant.html" title="15.7.1.6 GRANT Statement">
Section 15.7.1.6, “GRANT Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-optimization.html" title="10.2.3 Optimizing INFORMATION_SCHEMA Queries">
Section 10.2.3, “Optimizing INFORMATION_SCHEMA Queries”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="privileges-provided.html" title="8.2.2 Privileges Provided by MySQL">
Section 8.2.2, “Privileges Provided by MySQL”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="rename-user.html" title="15.7.1.7 RENAME USER Statement">
Section 15.7.1.7, “RENAME USER Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-variables.html" title="19.5.1.39 Replication and Variables">
Section 19.5.1.39, “Replication and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="revoke.html" title="15.7.1.8 REVOKE Statement">
Section 15.7.1.8, “REVOKE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="log-destinations.html" title="7.4.1 Selecting General Query Log and Slow Query Log Output Destinations">
Section 7.4.1, “Selecting General Query Log and Slow Query Log Output Destinations”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="set-password.html" title="15.7.1.10 SET PASSWORD Statement">
Section 15.7.1.10, “SET PASSWORD Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-gtids-howto.html" title="19.1.3.4 Setting Up Replication Using GTIDs">
Section 19.1.3.4, “Setting Up Replication Using GTIDs”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="commit.html" title="15.3.1 START TRANSACTION, COMMIT, and ROLLBACK Statements">
Section 15.3.1, “START TRANSACTION, COMMIT, and ROLLBACK Statements”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
read_rnd_buffer_size
</h3>
<dl>
<dt>
<a class="xref" href="memory-use.html" title="10.12.3.1 How MySQL Uses Memory">
Section 10.12.3.1, “How MySQL Uses Memory”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mrr-optimization.html" title="10.2.1.11 Multi-Range Read Optimization">
Section 10.2.1.11, “Multi-Range Read Optimization”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="order-by-optimization.html" title="10.2.1.16 ORDER BY Optimization">
Section 10.2.1.16, “ORDER BY Optimization”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
regexp_stack_limit
</h3>
<dl>
<dt>
<a class="xref" href="regexp.html" title="14.8.2 Regular Expressions">
Section 14.8.2, “Regular Expressions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
regexp_time_limit
</h3>
<dl>
<dt>
<a class="xref" href="regexp.html" title="14.8.2 Regular Expressions">
Section 14.8.2, “Regular Expressions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
relay
</h3>
<dl>
<dt>
<a class="xref" href="channels-startup-options.html" title="19.2.2.3 Startup Options and Replication Channels">
Section 19.2.2.3, “Startup Options and Replication Channels”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
relay_log
</h3>
<dl>
<dt>
<a class="xref" href="replication-howto-additionalslaves.html" title="19.1.2.8 Adding Replicas to a Replication Environment">
Section 19.1.2.8, “Adding Replicas to a Replication Environment”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-frequently-asked-questions.html" title="20.10 Frequently Asked Questions">
Section 20.10, “Frequently Asked Questions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-solutions-performance.html" title="19.4.7 Improving Replication Performance">
Section 19.4.7, “Improving Replication Performance”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="channels-naming-conventions.html" title="19.2.2.4 Replication Channel Naming Conventions">
Section 19.2.2.4, “Replication Channel Naming Conventions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replica-logs-relaylog.html" title="19.2.4.1 The Relay Log">
Section 19.2.4.1, “The Relay Log”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
relay_log_basename
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
relay_log_index
</h3>
<dl>
<dt>
<a class="xref" href="replication-howto-additionalslaves.html" title="19.1.2.8 Adding Replicas to a Replication Environment">
Section 19.1.2.8, “Adding Replicas to a Replication Environment”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replica-logs-relaylog.html" title="19.2.4.1 The Relay Log">
Section 19.2.4.1, “The Relay Log”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
relay_log_info_file
</h3>
<dl>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
relay_log_info_repository
</h3>
<dl>
<dt>
<a class="xref" href="replication-solutions-unexpected-replica-halt.html" title="19.4.2 Handling an Unexpected Halt of a Replica">
Section 19.4.2, “Handling an Unexpected Halt of a Replica”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
relay_log_purge
</h3>
<dl>
<dt>
<a class="xref" href="replication-solutions-unexpected-replica-halt.html" title="19.4.2 Handling an Unexpected Halt of a Replica">
Section 19.4.2, “Handling an Unexpected Halt of a Replica”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="show-replica-status.html" title="15.7.7.35 SHOW REPLICA STATUS Statement">
Section 15.7.7.35, “SHOW REPLICA STATUS Statement”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
relay_log_recovery
</h3>
<dl>
<dt>
<a class="xref" href="replication-solutions-unexpected-replica-halt.html" title="19.4.2 Handling an Unexpected Halt of a Replica">
Section 19.4.2, “Handling an Unexpected Halt of a Replica”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
relay_log_space_limit
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replica-io-thread-states.html" title="10.14.5 Replication I/O (Receiver) Thread States">
Section 10.14.5, “Replication I/O (Receiver) Thread States”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="channels-startup-options.html" title="19.2.2.3 Startup Options and Replication Channels">
Section 19.2.2.3, “Startup Options and Replication Channels”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
replica
</h3>
<dl>
<dt>
<a class="xref" href="channels-startup-options.html" title="19.2.2.3 Startup Options and Replication Channels">
Section 19.2.2.3, “Startup Options and Replication Channels”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
replica_allow_batching
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-replication-preparation.html" title="25.7.5 Preparing the NDB Cluster for Replication">
Section 25.7.5, “Preparing the NDB Cluster for Replication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-replication-starting.html" title="25.7.6 Starting NDB Cluster Replication (Single Replication Channel)">
Section 25.7.6, “Starting NDB Cluster Replication (Single Replication Channel)”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
replica_checkpoint_group
</h3>
<dl>
<dt>
<a class="xref" href="replication-functions-synchronization.html" title="14.18.4 Position-Based Synchronization Functions">
Section 14.18.4, “Position-Based Synchronization Functions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="channels-startup-options.html" title="19.2.2.3 Startup Options and Replication Channels">
Section 19.2.2.3, “Startup Options and Replication Channels”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
replica_checkpoint_period
</h3>
<dl>
<dt>
<a class="xref" href="replication-functions-synchronization.html" title="14.18.4 Position-Based Synchronization Functions">
Section 14.18.4, “Position-Based Synchronization Functions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
replica_compressed_protocol
</h3>
<dl>
<dt>
<a class="xref" href="change-replication-source-to.html" title="15.4.2.2 CHANGE REPLICATION SOURCE TO Statement">
Section 15.4.2.2, “CHANGE REPLICATION SOURCE TO Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="connection-compression-control.html" title="6.2.8 Connection Compression Control">
Section 6.2.8, “Connection Compression Control”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log-transaction-compression.html#binary-log-transaction-compression-monitoring" title="7.4.4.5.3 Monitoring Binary Log Transaction Compression">
Section 7.4.4.5.3, “Monitoring Binary Log Transaction Compression”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
replica_exec_mode
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-replication-issues.html" title="25.7.3 Known Issues in NDB Cluster Replication">
Section 25.7.3, “Known Issues in NDB Cluster Replication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-memory.html" title="19.5.1.21 Replication and MEMORY Tables">
Section 19.5.1.21, “Replication and MEMORY Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-rbr-usage.html" title="19.2.1.2 Usage of Row-Based Logging and Replication">
Section 19.2.1.2, “Usage of Row-Based Logging and Replication”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
replica_load_tmpdir
</h3>
<dl>
<dt>
<a class="xref" href="replication-solutions-backups-rawdata.html" title="19.4.1.2 Backing Up Raw Data from a Replica">
Section 19.4.1.2, “Backing Up Raw Data from a Replica”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="backup-methods.html" title="9.2 Database Backup Methods">
Section 9.2, “Database Backup Methods”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-options.html" title="7.1.7 Server Command Options">
Section 7.1.7, “Server Command Options”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="temporary-files.html" title="B.3.3.5 Where MySQL Stores Temporary Files">
Section B.3.3.5, “Where MySQL Stores Temporary Files”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
replica_max_allowed_packet
</h3>
<dl>
<dt>
<a class="xref" href="binary-log-transaction-compression.html#binary-log-transaction-compression-enabled" title="7.4.4.5.1 Behaviors When Binary Log Transaction Compression is Enabled">
Section 7.4.4.5.1, “Behaviors When Binary Log Transaction Compression is Enabled”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-limitations.html" title="20.3.2 Group Replication Limitations">
Section 20.3.2, “Group Replication Limitations”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-performance-message-fragmentation.html" title="20.7.5 Message Fragmentation">
Section 20.7.5, “Message Fragmentation”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-max-allowed-packet.html" title="19.5.1.20 Replication and max_allowed_packet">
Section 19.5.1.20, “Replication and max_allowed_packet”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
replica_net_timeout
</h3>
<dl>
<dt>
<a class="xref" href="change-replication-source-to.html" title="15.4.2.2 CHANGE REPLICATION SOURCE TO Statement">
Section 15.4.2.2, “CHANGE REPLICATION SOURCE TO Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-administration-status.html" title="19.1.7.1 Checking Replication Status">
Section 19.1.7.1, “Checking Replication Status”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-shutdowns.html" title="19.5.1.28 Replication and Source or Replica Shutdowns">
Section 19.5.1.28, “Replication and Source or Replica Shutdowns”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replica-io-thread-states.html" title="10.14.5 Replication I/O (Receiver) Thread States">
Section 10.14.5, “Replication I/O (Receiver) Thread States”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
replica_parallel_type
</h3>
<dl>
<dt>
<a class="xref" href="binary-log-transaction-compression.html#binary-log-transaction-compression-enabled" title="7.4.4.5.1 Behaviors When Binary Log Transaction Compression is Enabled">
Section 7.4.4.5.1, “Behaviors When Binary Log Transaction Compression is Enabled”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-binary-log.html" title="19.1.6.4 Binary Logging Options and Variables">
Section 19.1.6.4, “Binary Logging Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-requirements.html" title="20.3.1 Group Replication Requirements">
Section 20.3.1, “Group Replication Requirements”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-threads-monitor-worker.html" title="19.2.3.2 Monitoring Replication Applier Worker Threads">
Section 19.2.3.2, “Monitoring Replication Applier Worker Threads”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-replication-mta.html" title="25.7.11 NDB Cluster Replication Using the Multithreaded Applier">
Section 25.7.11, “NDB Cluster Replication Using the Multithreaded Applier”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-transaction-inconsistencies.html" title="19.5.1.34 Replication and Transaction Inconsistencies">
Section 19.5.1.34, “Replication and Transaction Inconsistencies”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
replica_parallel_workers
</h3>
<dl>
<dt>
<a class="xref" href="change-replication-source-to.html" title="15.4.2.2 CHANGE REPLICATION SOURCE TO Statement">
Section 15.4.2.2, “CHANGE REPLICATION SOURCE TO Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="clone-plugin-replication.html" title="7.6.7.7 Cloning for Replication">
Section 7.6.7.7, “Cloning for Replication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-requirements.html" title="20.3.1 Group Replication Requirements">
Section 20.3.1, “Group Replication Requirements”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-gtids-lifecycle.html" title="19.1.3.2 GTID Life Cycle">
Section 19.1.3.2, “GTID Life Cycle”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-multi-source.html" title="19.1.5 MySQL Multi-Source Replication">
Section 19.1.5, “MySQL Multi-Source Replication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-replication-mta.html" title="25.7.11 NDB Cluster Replication Using the Multithreaded Applier">
Section 25.7.11, “NDB Cluster Replication Using the Multithreaded Applier”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-replication-tables.html" title="29.12.11 Performance Schema Replication Tables">
Section 29.12.11, “Performance Schema Replication Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-max-allowed-packet.html" title="19.5.1.20 Replication and max_allowed_packet">
Section 19.5.1.20, “Replication and max_allowed_packet”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-transaction-inconsistencies.html" title="19.5.1.34 Replication and Transaction Inconsistencies">
Section 19.5.1.34, “Replication and Transaction Inconsistencies”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-channels.html" title="19.2.2 Replication Channels">
Section 19.2.2, “Replication Channels”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replica-sql-thread-states.html" title="10.14.6 Replication SQL Thread States">
Section 10.14.6, “Replication SQL Thread States”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-threads.html" title="19.2.3 Replication Threads">
Section 19.2.3, “Replication Threads”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="start-replica.html" title="15.4.2.4 START REPLICA Statement">
Section 15.4.2.4, “START REPLICA Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="stop-replica.html" title="15.4.2.5 STOP REPLICA Statement">
Section 15.4.2.5, “STOP REPLICA Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-replication-applier-status-by-worker-table.html" title="29.12.11.7 The replication_applier_status_by_worker Table">
Section 29.12.11.7, “The replication_applier_status_by_worker Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
replica_pending_jobs_size_max
</h3>
<dl>
<dt>
<a class="xref" href="memory-use.html" title="10.12.3.1 How MySQL Uses Memory">
Section 10.12.3.1, “How MySQL Uses Memory”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-threads-monitor-worker.html" title="19.2.3.2 Monitoring Replication Applier Worker Threads">
Section 19.2.3.2, “Monitoring Replication Applier Worker Threads”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-max-allowed-packet.html" title="19.5.1.20 Replication and max_allowed_packet">
Section 19.5.1.20, “Replication and max_allowed_packet”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replica-sql-thread-states.html" title="10.14.6 Replication SQL Thread States">
Section 10.14.6, “Replication SQL Thread States”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
replica_preserve_commit_order
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-binary-log.html" title="19.1.6.4 Binary Logging Options and Variables">
Section 19.1.6.4, “Binary Logging Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-requirements.html" title="20.3.1 Group Replication Requirements">
Section 20.3.1, “Group Replication Requirements”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-gtids-lifecycle.html" title="19.1.3.2 GTID Life Cycle">
Section 19.1.3.2, “GTID Life Cycle”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-replication-mta.html" title="25.7.11 NDB Cluster Replication Using the Multithreaded Applier">
Section 25.7.11, “NDB Cluster Replication Using the Multithreaded Applier”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-transaction-inconsistencies.html" title="19.5.1.34 Replication and Transaction Inconsistencies">
Section 19.5.1.34, “Replication and Transaction Inconsistencies”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-gtids-assign-anon.html" title="19.1.3.6 Replication From a Source Without GTIDs to a Replica With GTIDs">
Section 19.1.3.6, “Replication From a Source Without GTIDs to a Replica With GTIDs”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replica-io-thread-states.html" title="10.14.5 Replication I/O (Receiver) Thread States">
Section 10.14.5, “Replication I/O (Receiver) Thread States”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="start-replica.html" title="15.4.2.4 START REPLICA Statement">
Section 15.4.2.4, “START REPLICA Statement”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
replica_skip_errors
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
replica_sql_verify_checksum
</h3>
<dl>
<dt>
<a class="xref" href="glossary.html" title="MySQL Glossary">
MySQL Glossary
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log.html" title="7.4.4 The Binary Log">
Section 7.4.4, “The Binary Log”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
replica_transaction_retries
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-timeout.html" title="19.5.1.32 Replication Retries and Timeouts">
Section 19.5.1.32, “Replication Retries and Timeouts”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-replication-applier-status-table.html" title="29.12.11.5 The replication_applier_status Table">
Section 29.12.11.5, “The replication_applier_status Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
replica_type_conversions
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-replication-issues.html" title="25.7.3 Known Issues in NDB Cluster Replication">
Section 25.7.3, “Known Issues in NDB Cluster Replication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
replication_optimize_for_static_plugin_config
</h3>
<dl>
<dt>
<a class="xref" href="replication-semisync-interface.html" title="19.4.10.2 Configuring Semisynchronous Replication">
Section 19.4.10.2, “Configuring Semisynchronous Replication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-semisync.html" title="19.4.10 Semisynchronous Replication">
Section 19.4.10, “Semisynchronous Replication”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
replication_sender_observe_commit_only
</h3>
<dl>
<dt>
<a class="xref" href="replication-semisync-interface.html" title="19.4.10.2 Configuring Semisynchronous Replication">
Section 19.4.10.2, “Configuring Semisynchronous Replication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-semisync.html" title="19.4.10 Semisynchronous Replication">
Section 19.4.10, “Semisynchronous Replication”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
report_host
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-connection-security.html" title="20.6.1 Communication Stack for Connection Security Management">
Section 20.6.1, “Communication Stack for Connection Security Management”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-configuring-instances.html" title="20.2.1.2 Configuring an Instance for Group Replication">
Section 20.2.1.2, “Configuring an Instance for Group Replication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-distributed-recovery-connections.html" title="20.5.4.1 Connections for Distributed Recovery">
Section 20.5.4.1, “Connections for Distributed Recovery”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-deploying-locally.html" title="20.2.2 Deploying Group Replication Locally">
Section 20.2.2, “Deploying Group Replication Locally”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
report_password
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
report_port
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-distributed-recovery-connections.html" title="20.5.4.1 Connections for Distributed Recovery">
Section 20.5.4.1, “Connections for Distributed Recovery”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-frequently-asked-questions.html" title="20.10 Frequently Asked Questions">
Section 20.10, “Frequently Asked Questions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-distributed-recovery-connections.html#group-replication-distributed-recovery-connections-endpoints" title="20.5.4.1.1 Selecting addresses for distributed recovery endpoints">
Section 20.5.4.1.1, “Selecting addresses for distributed recovery endpoints”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
report_user
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
require_row_format
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
require_secure_transport
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-connection-security.html" title="20.6.1 Communication Stack for Connection Security Management">
Section 20.6.1, “Communication Stack for Connection Security Management”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="using-encrypted-connections.html" title="8.3.1 Configuring MySQL to Use Encrypted Connections">
Section 8.3.1, “Configuring MySQL to Use Encrypted Connections”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="transport-protocols.html" title="6.2.7 Connection Transport Protocols">
Section 6.2.7, “Connection Transport Protocols”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="fips-mode.html" title="8.8 FIPS Support">
Section 8.8, “FIPS Support”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="encrypted-connections.html" title="8.3 Using Encrypted Connections">
Section 8.3, “Using Encrypted Connections”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="x-plugin-encrypted-connections.html" title="22.5.3 Using Encrypted Connections with X Plugin">
Section 22.5.3, “Using Encrypted Connections with X Plugin”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
restrict_fk_on_non_standard_key
</h3>
<dl>
<dt>
<a class="xref" href="ansi-diff-foreign-keys.html" title="1.7.2.3 FOREIGN KEY Constraint Differences">
Section 1.7.2.3, “FOREIGN KEY Constraint Differences”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="create-table-foreign-keys.html" title="15.1.20.5 FOREIGN KEY Constraints">
Section 15.1.20.5, “FOREIGN KEY Constraints”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
resultset_metadata
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
rewriter_enabled
</h3>
<dl>
<dt>
<a class="xref" href="rewriter-query-rewrite-plugin-reference.html#rewriter-query-rewrite-plugin-system-variables" title="7.6.4.3.3 Rewriter Query Rewrite Plugin System Variables">
Section 7.6.4.3.3, “Rewriter Query Rewrite Plugin System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="rewriter-query-rewrite-plugin-usage.html" title="7.6.4.2 Using the Rewriter Query Rewrite Plugin">
Section 7.6.4.2, “Using the Rewriter Query Rewrite Plugin”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
rewriter_enabled_for_threads_without_privilege_checks
</h3>
<dl>
<dt>
<a class="xref" href="rewriter-query-rewrite-plugin-reference.html#rewriter-query-rewrite-plugin-system-variables" title="7.6.4.3.3 Rewriter Query Rewrite Plugin System Variables">
Section 7.6.4.3.3, “Rewriter Query Rewrite Plugin System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="rewriter-query-rewrite-plugin-usage.html" title="7.6.4.2 Using the Rewriter Query Rewrite Plugin">
Section 7.6.4.2, “Using the Rewriter Query Rewrite Plugin”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
rewriter_verbose
</h3>
<dl>
<dt>
<a class="xref" href="rewriter-query-rewrite-plugin-reference.html#rewriter-query-rewrite-plugin-system-variables" title="7.6.4.3.3 Rewriter Query Rewrite Plugin System Variables">
Section 7.6.4.3.3, “Rewriter Query Rewrite Plugin System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
rpl_read_size
</h3>
<dl>
<dt>
<a class="xref" href="memory-use.html" title="10.12.3.1 How MySQL Uses Memory">
Section 10.12.3.1, “How MySQL Uses Memory”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-solutions-performance.html" title="19.4.7 Improving Replication Performance">
Section 19.4.7, “Improving Replication Performance”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
rpl_semi_sync_master_enabled
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-source.html" title="19.1.6.2 Replication Source Options and Variables">
Section 19.1.6.2, “Replication Source Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
rpl_semi_sync_master_timeout
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-source.html" title="19.1.6.2 Replication Source Options and Variables">
Section 19.1.6.2, “Replication Source Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
rpl_semi_sync_master_trace_level
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-source.html" title="19.1.6.2 Replication Source Options and Variables">
Section 19.1.6.2, “Replication Source Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
rpl_semi_sync_master_wait_for_slave_count
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-source.html" title="19.1.6.2 Replication Source Options and Variables">
Section 19.1.6.2, “Replication Source Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
rpl_semi_sync_master_wait_no_slave
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-source.html" title="19.1.6.2 Replication Source Options and Variables">
Section 19.1.6.2, “Replication Source Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
rpl_semi_sync_master_wait_point
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-source.html" title="19.1.6.2 Replication Source Options and Variables">
Section 19.1.6.2, “Replication Source Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
rpl_semi_sync_replica_enabled
</h3>
<dl>
<dt>
<a class="xref" href="replication-semisync-interface.html" title="19.4.10.2 Configuring Semisynchronous Replication">
Section 19.4.10.2, “Configuring Semisynchronous Replication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
rpl_semi_sync_replica_trace_level
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
rpl_semi_sync_slave_enabled
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
rpl_semi_sync_slave_trace_level
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
rpl_semi_sync_source_enabled
</h3>
<dl>
<dt>
<a class="xref" href="replication-semisync-interface.html" title="19.4.10.2 Configuring Semisynchronous Replication">
Section 19.4.10.2, “Configuring Semisynchronous Replication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-source.html" title="19.1.6.2 Replication Source Options and Variables">
Section 19.1.6.2, “Replication Source Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-semisync-monitoring.html" title="19.4.10.3 Semisynchronous Replication Monitoring">
Section 19.4.10.3, “Semisynchronous Replication Monitoring”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
rpl_semi_sync_source_timeout
</h3>
<dl>
<dt>
<a class="xref" href="replication-semisync-interface.html" title="19.4.10.2 Configuring Semisynchronous Replication">
Section 19.4.10.2, “Configuring Semisynchronous Replication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-source.html" title="19.1.6.2 Replication Source Options and Variables">
Section 19.1.6.2, “Replication Source Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
rpl_semi_sync_source_trace_level
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-source.html" title="19.1.6.2 Replication Source Options and Variables">
Section 19.1.6.2, “Replication Source Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
rpl_semi_sync_source_wait_for_replica_count
</h3>
<dl>
<dt>
<a class="xref" href="replication-semisync-interface.html" title="19.4.10.2 Configuring Semisynchronous Replication">
Section 19.4.10.2, “Configuring Semisynchronous Replication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-source.html" title="19.1.6.2 Replication Source Options and Variables">
Section 19.1.6.2, “Replication Source Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
rpl_semi_sync_source_wait_no_replica
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-source.html" title="19.1.6.2 Replication Source Options and Variables">
Section 19.1.6.2, “Replication Source Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
rpl_semi_sync_source_wait_point
</h3>
<dl>
<dt>
<a class="xref" href="replication-semisync-interface.html" title="19.4.10.2 Configuring Semisynchronous Replication">
Section 19.4.10.2, “Configuring Semisynchronous Replication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-source.html" title="19.1.6.2 Replication Source Options and Variables">
Section 19.1.6.2, “Replication Source Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-semisync.html" title="19.4.10 Semisynchronous Replication">
Section 19.4.10, “Semisynchronous Replication”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
rpl_stop_replica_timeout
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-transaction-inconsistencies.html" title="19.5.1.34 Replication and Transaction Inconsistencies">
Section 19.5.1.34, “Replication and Transaction Inconsistencies”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="stop-replica.html" title="15.4.2.5 STOP REPLICA Statement">
Section 15.4.2.5, “STOP REPLICA Statement”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
rpl_stop_slave_timeout
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<a name="sysvar-index-S">
</a>
<h3 class="title">
S
</h3>
<p>
[
<a class="link" href="dynindex-sysvar.html#sysvar-index-top">
index top
</a>
]
</p>
<dl>
<dt>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
schema_definition_cache
</h3>
<dl>
<dt>
<a class="xref" href="data-dictionary-object-cache.html" title="16.4 Dictionary Object Cache">
Section 16.4, “Dictionary Object Cache”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
secondary_engine_cost_threshold
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
secure_file_priv
</h3>
<dl>
<dt>
<a class="xref" href="import-table.html" title="15.2.6 IMPORT TABLE Statement">
Section 15.2.6, “IMPORT TABLE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="data-directory-initialization.html" title="2.9.1 Initializing the Data Directory">
Section 2.9.1, “Initializing the Data Directory”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="linux-installation-rpm.html" title="2.5.4 Installing MySQL on Linux Using RPM Packages from Oracle">
Section 2.5.4, “Installing MySQL on Linux Using RPM Packages from Oracle”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="load-data.html" title="15.2.9 LOAD DATA Statement">
Section 15.2.9, “LOAD DATA Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="security-against-attack.html" title="8.1.3 Making MySQL Secure Against Attackers">
Section 8.1.3, “Making MySQL Secure Against Attackers”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="data-masking-plugin-functions.html" title="8.5.3.4 MySQL Enterprise Data Masking and De-Identification Plugin Function Descriptions">
Section 8.5.3.4, “MySQL Enterprise Data Masking and De-Identification Plugin Function Descriptions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="source-configuration-options.html" title="2.8.7 MySQL Source-Configuration Options">
Section 2.8.7, “MySQL Source-Configuration Options”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="privileges-provided.html" title="8.2.2 Privileges Provided by MySQL">
Section 8.2.2, “Privileges Provided by MySQL”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-redo-log.html" title="17.6.5 Redo Log">
Section 17.6.5, “Redo Log”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="select-into.html" title="15.2.13.1 SELECT ... INTO Statement">
Section 15.2.13.1, “SELECT ... INTO Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="selinux-file-context.html" title="8.7.4 SELinux File Context">
Section 8.7.4, “SELinux File Context”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="string-functions.html" title="14.8 String Functions and Operators">
Section 14.8, “String Functions and Operators”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="data-masking-plugin-usage.html" title="8.5.3.2 Using the MySQL Enterprise Data Masking and De-Identification Plugin">
Section 8.5.3.2, “Using the MySQL Enterprise Data Masking and De-Identification Plugin”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
select_into_buffer_size
</h3>
<dl>
<dt>
<a class="xref" href="select-into.html" title="15.2.13.1 SELECT ... INTO Statement">
Section 15.2.13.1, “SELECT ... INTO Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
select_into_disk_sync
</h3>
<dl>
<dt>
<a class="xref" href="select-into.html" title="15.2.13.1 SELECT ... INTO Statement">
Section 15.2.13.1, “SELECT ... INTO Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
select_into_disk_sync_delay
</h3>
<dl>
<dt>
<a class="xref" href="select-into.html" title="15.2.13.1 SELECT ... INTO Statement">
Section 15.2.13.1, “SELECT ... INTO Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
server_id
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-adding-instances.html#group-replication-adding-a-second-instance" title="20.2.1.6.1 Adding a Second Instance">
Section 20.2.1.6.1, “Adding a Second Instance”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-howto-additionalslaves.html" title="19.1.2.8 Adding Replicas to a Replication Environment">
Section 19.1.2.8, “Adding Replicas to a Replication Environment”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-configurator-workflow-server.html#server-advanced-options" title="2.3.2.1.7 Advanced Options">
Section 2.3.2.1.7, “Advanced Options”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="audit-log-file-formats.html" title="8.4.5.4 Audit Log File Formats">
Section 8.4.5.4, “Audit Log File Formats”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binlog-replication-configuration-overview.html" title="19.1.1 Binary Log File Position Based Replication Configuration Overview">
Section 19.1.1, “Binary Log File Position Based Replication Configuration Overview”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-binary-log.html" title="19.1.6.4 Binary Logging Options and Variables">
Section 19.1.6.4, “Binary Logging Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-requirements.html" title="20.3.1 Group Replication Requirements">
Section 20.3.1, “Group Replication Requirements”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="miscellaneous-functions.html" title="14.23 Miscellaneous Functions">
Section 14.23, “Miscellaneous Functions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysqlbinlog.html" title="6.6.9 mysqlbinlog — Utility for Processing Binary Log Files">
Section 6.6.9, “mysqlbinlog — Utility for Processing Binary Log Files”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-replication-tables.html" title="29.12.11 Performance Schema Replication Tables">
Section 29.12.11, “Performance Schema Replication Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options.html" title="19.1.6 Replication and Binary Logging Options and Variables">
Section 19.1.6, “Replication and Binary Logging Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-source.html" title="19.1.6.2 Replication Source Options and Variables">
Section 19.1.6.2, “Replication Source Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-howto-slavebaseconfig.html" title="19.1.2.2 Setting the Replica Configuration">
Section 19.1.2.2, “Setting the Replica Configuration”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-howto-masterbaseconfig.html" title="19.1.2.1 Setting the Replication Source Configuration">
Section 19.1.2.1, “Setting the Replication Source Configuration”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-gtids-howto.html" title="19.1.3.4 Setting Up Replication Using GTIDs">
Section 19.1.3.4, “Setting Up Replication Using GTIDs”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="show-replica-status.html" title="15.7.7.35 SHOW REPLICA STATUS Statement">
Section 15.7.7.35, “SHOW REPLICA STATUS Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log.html" title="7.4.4 The Binary Log">
Section 7.4.4, “The Binary Log”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-problems.html" title="19.5.4 Troubleshooting Replication">
Section 19.5.4, “Troubleshooting Replication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-rbr-usage.html" title="19.2.1.2 Usage of Row-Based Logging and Replication">
Section 19.2.1.2, “Usage of Row-Based Logging and Replication”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
server_id_bits
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
server_uuid
</h3>
<dl>
<dt>
<a class="xref" href="replication-binlog-encryption-encryption-keys.html" title="19.3.2.2 Binary Log Encryption Keys">
Section 19.3.2.2, “Binary Log Encryption Keys”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="change-replication-source-to.html" title="15.4.2.2 CHANGE REPLICATION SOURCE TO Statement">
Section 15.4.2.2, “CHANGE REPLICATION SOURCE TO Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-changing-group-mode.html" title="20.5.1.2 Changing the Group Mode">
Section 20.5.1.2, “Changing the Group Mode”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-change-primary.html" title="20.5.1.1 Changing the Primary">
Section 20.5.1.1, “Changing the Primary”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-gtids-concepts.html" title="19.1.3.1 GTID Format and Storage">
Section 19.1.3.1, “GTID Format and Storage”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-replication-tables.html" title="29.12.11 Performance Schema Replication Tables">
Section 29.12.11, “Performance Schema Replication Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-single-primary-mode.html#group-replication-primary-election" title="20.1.3.1.1 Primary Election Algorithm">
Section 20.1.3.1.1, “Primary Election Algorithm”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options.html" title="19.1.6 Replication and Binary Logging Options and Variables">
Section 19.1.6, “Replication and Binary Logging Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-gtids-assign-anon.html" title="19.1.3.6 Replication From a Source Without GTIDs to a Replica With GTIDs">
Section 19.1.3.6, “Replication From a Source Without GTIDs to a Replica With GTIDs”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="show-replica-status.html" title="15.7.7.35 SHOW REPLICA STATUS Statement">
Section 15.7.7.35, “SHOW REPLICA STATUS Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-gtids-functions.html" title="19.1.3.8 Stored Function Examples to Manipulate GTIDs">
Section 19.1.3.8, “Stored Function Examples to Manipulate GTIDs”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-log-status-table.html" title="29.12.22.5 The log_status Table">
Section 29.12.22.5, “The log_status Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-replication-applier-configuration-table.html" title="29.12.11.2 The replication_applier_configuration Table">
Section 29.12.11.2, “The replication_applier_configuration Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-replication-connection-status-table.html" title="29.12.11.13 The replication_connection_status Table">
Section 29.12.11.13, “The replication_connection_status Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-replication-group-members.html" title="20.4.3 The replication_group_members Table">
Section 20.4.3, “The replication_group_members Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-enterprise-backup.html" title="20.5.6 Using MySQL Enterprise Backup with Group Replication">
Section 20.5.6, “Using MySQL Enterprise Backup with Group Replication”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
session_track_gtids
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-gtids.html" title="19.1.6.5 Global Transaction ID System Variables">
Section 19.1.6.5, “Global Transaction ID System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-mode-change-online-concepts.html" title="19.1.4.1 Replication Mode Concepts">
Section 19.1.4.1, “Replication Mode Concepts”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="session-state-tracking.html" title="7.1.18 Server Tracking of Client Session State">
Section 7.1.18, “Server Tracking of Client Session State”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
session_track_schema
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="session-state-tracking.html" title="7.1.18 Server Tracking of Client Session State">
Section 7.1.18, “Server Tracking of Client Session State”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
session_track_state_change
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="session-state-tracking.html" title="7.1.18 Server Tracking of Client Session State">
Section 7.1.18, “Server Tracking of Client Session State”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
session_track_system_variables
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="session-state-tracking.html" title="7.1.18 Server Tracking of Client Session State">
Section 7.1.18, “Server Tracking of Client Session State”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
session_track_transaction_info
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="session-state-tracking.html" title="7.1.18 Server Tracking of Client Session State">
Section 7.1.18, “Server Tracking of Client Session State”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
set_operations_buffer_size
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="switchable-optimizations.html" title="10.9.2 Switchable Optimizations">
Section 10.9.2, “Switchable Optimizations”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
sha
</h3>
<dl>
<dt>
<a class="xref" href="creating-ssl-rsa-files-using-mysql.html" title="8.3.3.1 Creating SSL and RSA Certificates and Keys using MySQL">
Section 8.3.3.1, “Creating SSL and RSA Certificates and Keys using MySQL”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="proxy-users.html" title="8.2.19 Proxy Users">
Section 8.2.19, “Proxy Users”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-status-variables.html" title="7.1.10 Server Status Variables">
Section 7.1.10, “Server Status Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="sha256-pluggable-authentication.html" title="8.4.1.3 SHA-256 Pluggable Authentication">
Section 8.4.1.3, “SHA-256 Pluggable Authentication”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
shared_memory
</h3>
<dl>
<dt>
<a class="xref" href="connection-options.html" title="6.2.3 Command Options for Connecting to the Server">
Section 6.2.3, “Command Options for Connecting to the Server”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="connecting.html" title="6.2.4 Connecting to the MySQL Server Using Command Options">
Section 6.2.4, “Connecting to the MySQL Server Using Command Options”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-command-options.html" title="6.5.1.1 mysql Client Options">
Section 6.5.1.1, “mysql Client Options”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysqladmin.html" title="6.5.2 mysqladmin — A MySQL Server Administration Program">
Section 6.5.2, “mysqladmin — A MySQL Server Administration Program”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysqlbinlog.html" title="6.6.9 mysqlbinlog — Utility for Processing Binary Log Files">
Section 6.6.9, “mysqlbinlog — Utility for Processing Binary Log Files”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysqlcheck.html" title="6.5.3 mysqlcheck — A Table Maintenance Program">
Section 6.5.3, “mysqlcheck — A Table Maintenance Program”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysqldump.html" title="6.5.4 mysqldump — A Database Backup Program">
Section 6.5.4, “mysqldump — A Database Backup Program”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysqlimport.html" title="6.5.5 mysqlimport — A Data Import Program">
Section 6.5.5, “mysqlimport — A Data Import Program”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysqlshow.html" title="6.5.6 mysqlshow — Display Database, Table, and Column Information">
Section 6.5.6, “mysqlshow — Display Database, Table, and Column Information”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysqlslap.html" title="6.5.7 mysqlslap — A Load Emulation Client">
Section 6.5.7, “mysqlslap — A Load Emulation Client”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="resetting-permissions.html#resetting-permissions-generic" title="B.3.3.2.3 Resetting the Root Password: Generic Instructions">
Section B.3.3.2.3, “Resetting the Root Password: Generic Instructions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="multiple-windows-command-line-servers.html" title="7.8.2.1 Starting Multiple MySQL Instances at the Windows Command Line">
Section 7.8.2.1, “Starting Multiple MySQL Instances at the Windows Command Line”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="windows-server-first-start.html" title="2.3.3.5 Starting the Server for the First Time">
Section 2.3.3.5, “Starting the Server for the First Time”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="features.html" title="1.2.2 The Main Features of MySQL">
Section 1.2.2, “The Main Features of MySQL”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-configurator-workflow-server.html#server-type-network" title="2.3.2.1.2 Type and Networking">
Section 2.3.2.1.2, “Type and Networking”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
shared_memory_base_name
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="multiple-windows-command-line-servers.html" title="7.8.2.1 Starting Multiple MySQL Instances at the Windows Command Line">
Section 7.8.2.1, “Starting Multiple MySQL Instances at the Windows Command Line”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
show_create_table_skip_secondary_engine
</h3>
<dl>
<dt>
<a class="xref" href="mysqldump.html" title="6.5.4 mysqldump — A Database Backup Program">
Section 6.5.4, “mysqldump — A Database Backup Program”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
show_create_table_verbosity
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
show_gipk_in_create_table_and_information_schema
</h3>
<dl>
<dt>
<a class="xref" href="create-table-gipks.html" title="15.1.20.11 Generated Invisible Primary Keys">
Section 15.1.20.11, “Generated Invisible Primary Keys”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-introduction.html" title="28.1 Introduction">
Section 28.1, “Introduction”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="show-columns.html" title="15.7.7.6 SHOW COLUMNS Statement">
Section 15.7.7.6, “SHOW COLUMNS Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="show-create-table.html" title="15.7.7.11 SHOW CREATE TABLE Statement">
Section 15.7.7.11, “SHOW CREATE TABLE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="show-index.html" title="15.7.7.23 SHOW INDEX Statement">
Section 15.7.7.23, “SHOW INDEX Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-columns-table.html" title="28.3.8 The INFORMATION_SCHEMA COLUMNS Table">
Section 28.3.8, “The INFORMATION_SCHEMA COLUMNS Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-statistics-table.html" title="28.3.34 The INFORMATION_SCHEMA STATISTICS Table">
Section 28.3.34, “The INFORMATION_SCHEMA STATISTICS Table”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
skip_external_locking
</h3>
<dl>
<dt>
<a class="xref" href="external-locking.html" title="10.11.5 External Locking">
Section 10.11.5, “External Locking”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
skip_name_resolve
</h3>
<dl>
<dt>
<a class="xref" href="host-cache.html" title="7.1.12.3 DNS Lookups and the Host Cache">
Section 7.1.12.3, “DNS Lookups and the Host Cache”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-frequently-asked-questions.html" title="20.10 Frequently Asked Questions">
Section 20.10, “Frequently Asked Questions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="data-directory-initialization.html" title="2.9.1 Initializing the Data Directory">
Section 2.9.1, “Initializing the Data Directory”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="network-namespace-support.html" title="7.1.14 Network Namespace Support">
Section 7.1.14, “Network Namespace Support”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="windows-testing.html" title="2.3.3.9 Testing The MySQL Installation">
Section 2.3.3.9, “Testing The MySQL Installation”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="problems-connecting.html" title="8.2.22 Troubleshooting Problems Connecting to MySQL">
Section 8.2.22, “Troubleshooting Problems Connecting to MySQL”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
skip_networking
</h3>
<dl>
<dt>
<a class="xref" href="can-not-connect-to-server.html" title="B.3.2.2 Can't connect to [local] MySQL server">
Section B.3.2.2, “Can't connect to [local] MySQL server”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="host-cache.html" title="7.1.12.3 DNS Lookups and the Host Cache">
Section 7.1.12.3, “DNS Lookups and the Host Cache”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="faqs-replication.html" title="A.14 MySQL 8.4 FAQ: Replication">
Section A.14, “MySQL 8.4 FAQ: Replication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="gone-away.html" title="B.3.2.7 MySQL server has gone away">
Section B.3.2.7, “MySQL server has gone away”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="pluggable-authentication.html" title="8.2.17 Pluggable Authentication">
Section 8.2.17, “Pluggable Authentication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="resetting-permissions.html#resetting-permissions-generic" title="B.3.3.2.3 Resetting the Root Password: Generic Instructions">
Section B.3.3.2.3, “Resetting the Root Password: Generic Instructions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-options.html" title="7.1.7 Server Command Options">
Section 7.1.7, “Server Command Options”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-howto-masterbaseconfig.html" title="19.1.2.1 Setting the Replication Source Configuration">
Section 19.1.2.1, “Setting the Replication Source Configuration”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-ndbinfo-processes.html" title="25.6.17.51 The ndbinfo processes Table">
Section 25.6.17.51, “The ndbinfo processes Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="problems-connecting.html" title="8.2.22 Troubleshooting Problems Connecting to MySQL">
Section 8.2.22, “Troubleshooting Problems Connecting to MySQL”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-problems.html" title="19.5.4 Troubleshooting Replication">
Section 19.5.4, “Troubleshooting Replication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="x-plugin-status-variables.html" title="22.5.6.3 X Plugin Status Variables">
Section 22.5.6.3, “X Plugin Status Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
skip_replica_start
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="start-group-replication.html" title="15.4.3.1 START GROUP_REPLICATION Statement">
Section 15.4.3.1, “START GROUP_REPLICATION Statement”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
skip_show_database
</h3>
<dl>
<dt>
<a class="xref" href="server-options.html" title="7.1.7 Server Command Options">
Section 7.1.7, “Server Command Options”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
skip_slave_start
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
slave_allow_batching
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
slave_checkpoint_group
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
slave_checkpoint_period
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
slave_compressed_protocol
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
slave_exec_mode
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
slave_load_tmpdir
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
slave_max_allowed_packet
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
slave_net_timeout
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
slave_parallel_type
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
slave_parallel_workers
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
slave_pending_jobs_size_max
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
slave_preserve_commit_order
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
slave_skip_errors
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
slave_sql_verify_checksum
</h3>
<dl>
<dt>
<a class="xref" href="glossary.html" title="MySQL Glossary">
MySQL Glossary
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
slave_transaction_retries
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
slave_type_conversions
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
slow_launch_time
</h3>
<dl>
<dt>
<a class="xref" href="server-status-variables.html" title="7.1.10 Server Status Variables">
Section 7.1.10, “Server Status Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
slow_query_log
</h3>
<dl>
<dt>
<a class="xref" href="log-destinations.html" title="7.4.1 Selecting General Query Log and Slow Query Log Output Destinations">
Section 7.4.1, “Selecting General Query Log and Slow Query Log Output Destinations”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="slow-query-log.html" title="7.4.5 The Slow Query Log">
Section 7.4.5, “The Slow Query Log”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
slow_query_log_file
</h3>
<dl>
<dt>
<a class="xref" href="log-destinations.html" title="7.4.1 Selecting General Query Log and Slow Query Log Output Destinations">
Section 7.4.1, “Selecting General Query Log and Slow Query Log Output Destinations”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="slow-query-log.html" title="7.4.5 The Slow Query Log">
Section 7.4.5, “The Slow Query Log”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
socket
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="x-plugin-options-system-variables.html" title="22.5.6.2 X Plugin Options and System Variables">
Section 22.5.6.2, “X Plugin Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
sort_buffer_size
</h3>
<dl>
<dt>
<a class="xref" href="myisam-repair.html" title="9.6.3 How to Repair MyISAM Tables">
Section 9.6.3, “How to Repair MyISAM Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="order-by-optimization.html" title="10.2.1.16 ORDER BY Optimization">
Section 10.2.1.16, “ORDER BY Optimization”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-options.html" title="7.1.7 Server Command Options">
Section 7.1.7, “Server Command Options”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-status-variables.html" title="7.1.10 Server Status Variables">
Section 7.1.10, “Server Status Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="set-variable.html" title="15.7.6.1 SET Syntax for Variable Assignment">
Section 15.7.6.1, “SET Syntax for Variable Assignment”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="using-system-variables.html" title="7.1.9 Using System Variables">
Section 7.1.9, “Using System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
source_verify_checksum
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-binary-log.html" title="19.1.6.4 Binary Logging Options and Variables">
Section 19.1.6.4, “Binary Logging Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="glossary.html" title="MySQL Glossary">
MySQL Glossary
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log.html" title="7.4.4 The Binary Log">
Section 7.4.4, “The Binary Log”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
sql_auto_is_null
</h3>
<dl>
<dt>
<a class="xref" href="comparison-operators.html" title="14.4.2 Comparison Functions and Operators">
Section 14.4.2, “Comparison Functions and Operators”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="create-table.html" title="15.1.20 CREATE TABLE Statement">
Section 15.1.20, “CREATE TABLE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log-mixed.html" title="7.4.4.3 Mixed Binary Logging Format">
Section 7.4.4.3, “Mixed Binary Logging Format”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-variables.html" title="19.5.1.39 Replication and Variables">
Section 19.5.1.39, “Replication and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log.html" title="7.4.4 The Binary Log">
Section 7.4.4, “The Binary Log”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
sql_big_selects
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
sql_buffer_result
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
sql_generate_invisible_primary_key
</h3>
<dl>
<dt>
<a class="xref" href="create-table-gipks.html" title="15.1.20.11 Generated Invisible Primary Keys">
Section 15.1.20.11, “Generated Invisible Primary Keys”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
sql_log_bin
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-binary-log.html" title="19.1.6.4 Binary Logging Options and Variables">
Section 19.1.6.4, “Binary Logging Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-gtids.html" title="20.4.1 GTIDs and Group Replication">
Section 20.4.1, “GTIDs and Group Replication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-replication-issues.html" title="25.7.3 Known Issues in NDB Cluster Replication">
Section 25.7.3, “Known Issues in NDB Cluster Replication”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysqlbinlog.html" title="6.6.9 mysqlbinlog — Utility for Processing Binary Log Files">
Section 6.6.9, “mysqlbinlog — Utility for Processing Binary Log Files”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-cluster-replication-schema.html" title="25.7.4 NDB Cluster Replication Schema and Tables">
Section 25.7.4, “NDB Cluster Replication Schema and Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="privileges-provided.html" title="8.2.2 Privileges Provided by MySQL">
Section 8.2.2, “Privileges Provided by MySQL”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="set-sql-log-bin.html" title="15.4.1.3 SET sql_log_bin Statement">
Section 15.4.1.3, “SET sql_log_bin Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="system-variable-privileges.html" title="7.1.9.1 System Variable Privileges">
Section 7.1.9.1, “System Variable Privileges”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="sys-diagnostics.html" title="30.4.4.2 The diagnostics() Procedure">
Section 30.4.4.2, “The diagnostics() Procedure”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="sys-ps-setup-reload-saved.html" title="30.4.4.12 The ps_setup_reload_saved() Procedure">
Section 30.4.4.12, “The ps_setup_reload_saved() Procedure”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="sys-ps-setup-save.html" title="30.4.4.14 The ps_setup_save() Procedure">
Section 30.4.4.14, “The ps_setup_save() Procedure”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="sys-ps-trace-statement-digest.html" title="30.4.4.22 The ps_trace_statement_digest() Procedure">
Section 30.4.4.22, “The ps_trace_statement_digest() Procedure”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="sys-ps-trace-thread.html" title="30.4.4.23 The ps_trace_thread() Procedure">
Section 30.4.4.23, “The ps_trace_thread() Procedure”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="sys-statement-performance-analyzer.html" title="30.4.4.25 The statement_performance_analyzer() Procedure">
Section 30.4.4.25, “The statement_performance_analyzer() Procedure”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
sql_log_off
</h3>
<dl>
<dt>
<a class="xref" href="glossary.html" title="MySQL Glossary">
MySQL Glossary
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="privileges-provided.html" title="8.2.2 Privileges Provided by MySQL">
Section 8.2.2, “Privileges Provided by MySQL”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="log-destinations.html" title="7.4.1 Selecting General Query Log and Slow Query Log Output Destinations">
Section 7.4.1, “Selecting General Query Log and Slow Query Log Output Destinations”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="query-log.html" title="7.4.3 The General Query Log">
Section 7.4.3, “The General Query Log”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
SQL_MODE
</h3>
<dl>
<dt>
<a class="xref" href="innodb-online-ddl-operations.html" title="17.12.1 Online DDL Operations">
Section 17.12.1, “Online DDL Operations”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
sql_mode
</h3>
<dl>
<dt>
<a class="xref" href="innodb-best-practices.html" title="17.1.2 Best Practices for InnoDB Tables">
Section 17.1.2, “Best Practices for InnoDB Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="create-event.html" title="15.1.13 CREATE EVENT Statement">
Section 15.1.13, “CREATE EVENT Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="create-procedure.html" title="15.1.17 CREATE PROCEDURE and CREATE FUNCTION Statements">
Section 15.1.17, “CREATE PROCEDURE and CREATE FUNCTION Statements”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="create-trigger.html" title="15.1.22 CREATE TRIGGER Statement">
Section 15.1.22, “CREATE TRIGGER Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="precision-math-expressions.html" title="14.24.3 Expression Handling">
Section 14.24.3, “Expression Handling”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="bug-reports.html" title="1.6 How to Report Bugs or Problems">
Section 1.6, “How to Report Bugs or Problems”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="load-data.html" title="15.2.9 LOAD DATA Statement">
Section 15.2.9, “LOAD DATA Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log-mixed.html" title="7.4.4.3 Mixed Binary Logging Format">
Section 7.4.4.3, “Mixed Binary Logging Format”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="compatibility.html" title="1.7 MySQL Standards Compliance">
Section 1.7, “MySQL Standards Compliance”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="upgrade-prerequisites.html" title="3.6 Preparing Your Installation for Upgrade">
Section 3.6, “Preparing Your Installation for Upgrade”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="using-date.html" title="B.3.4.2 Problems Using DATE Columns">
Section B.3.4.2, “Problems Using DATE Columns”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-variables.html" title="19.5.1.39 Replication and Variables">
Section 19.5.1.39, “Replication and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="sql-mode.html" title="7.1.11 Server SQL Modes">
Section 7.1.11, “Server SQL Modes”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="show-create-view.html" title="15.7.7.14 SHOW CREATE VIEW Statement">
Section 15.7.7.14, “SHOW CREATE VIEW Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="signal.html" title="15.6.7.5 SIGNAL Statement">
Section 15.6.7.5, “SIGNAL Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log.html" title="7.4.4 The Binary Log">
Section 7.4.4, “The Binary Log”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-views-table.html" title="28.3.47 The INFORMATION_SCHEMA VIEWS Table">
Section 28.3.47, “The INFORMATION_SCHEMA VIEWS Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="sys-list-add.html" title="30.4.5.7 The list_add() Function">
Section 30.4.5.7, “The list_add() Function”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="option-files.html" title="6.2.2.2 Using Option Files">
Section 6.2.2.2, “Using Option Files”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="using-system-variables.html" title="7.1.9 Using System Variables">
Section 7.1.9, “Using System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
sql_notes
</h3>
<dl>
<dt>
<a class="xref" href="error-interfaces.html" title="B.2 Error Information Interfaces">
Section B.2, “Error Information Interfaces”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="show-warnings.html" title="15.7.7.42 SHOW WARNINGS Statement">
Section 15.7.7.42, “SHOW WARNINGS Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="diagnostics-area.html" title="15.6.7.7 The MySQL Diagnostics Area">
Section 15.6.7.7, “The MySQL Diagnostics Area”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
sql_quote_show_create
</h3>
<dl>
<dt>
<a class="xref" href="information-functions.html" title="14.15 Information Functions">
Section 14.15, “Information Functions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="show-create-database.html" title="15.7.7.7 SHOW CREATE DATABASE Statement">
Section 15.7.7.7, “SHOW CREATE DATABASE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="show-create-table.html" title="15.7.7.11 SHOW CREATE TABLE Statement">
Section 15.7.7.11, “SHOW CREATE TABLE Statement”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
sql_replica_skip_counter
</h3>
<dl>
<dt>
<a class="xref" href="binary-log-transaction-compression.html#binary-log-transaction-compression-enabled" title="7.4.4.5.1 Behaviors When Binary Log Transaction Compression is Enabled">
Section 7.4.4.5.1, “Behaviors When Binary Log Transaction Compression is Enabled”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-gtids-restrictions.html" title="19.1.3.7 Restrictions on Replication with GTIDs">
Section 19.1.3.7, “Restrictions on Replication with GTIDs”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="show-replica-status.html" title="15.7.7.35 SHOW REPLICA STATUS Statement">
Section 15.7.7.35, “SHOW REPLICA STATUS Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-administration-skip.html#set-global-replica-sql-skip-counter" title="19.1.7.3.2.1 Skipping Transactions With SET GLOBAL sql_replica_skip_counter">
Section 19.1.7.3.2.1, “Skipping Transactions With
<code class="literal">
SET GLOBAL
sql_replica_skip_counter
</code>
”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
sql_require_primary_key
</h3>
<dl>
<dt>
<a class="xref" href="alter-table.html" title="15.1.9 ALTER TABLE Statement">
Section 15.1.9, “ALTER TABLE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="change-replication-source-to.html" title="15.4.2.2 CHANGE REPLICATION SOURCE TO Statement">
Section 15.4.2.2, “CHANGE REPLICATION SOURCE TO Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-requirements.html" title="20.3.1 Group Replication Requirements">
Section 20.3.1, “Group Replication Requirements”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-privilege-checks-gr.html" title="19.3.3.2 Privilege Checks For Group Replication Channels">
Section 19.3.3.2, “Privilege Checks For Group Replication Channels”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-privilege-checks-account.html" title="19.3.3.1 Privileges For The Replication PRIVILEGE_CHECKS_USER Account">
Section 19.3.3.1, “Privileges For The Replication PRIVILEGE_CHECKS_USER Account”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-privilege-checks.html" title="19.3.3 Replication Privilege Checks">
Section 19.3.3, “Replication Privilege Checks”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
sql_safe_updates
</h3>
<dl>
<dt>
<a class="xref" href="mysql-tips.html" title="6.5.1.6 mysql Client Tips">
Section 6.5.1.6, “mysql Client Tips”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="range-optimization.html" title="10.2.1.2 Range Optimization">
Section 10.2.1.2, “Range Optimization”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
sql_select_limit
</h3>
<dl>
<dt>
<a class="xref" href="mysql-tips.html" title="6.5.1.6 mysql Client Tips">
Section 6.5.1.6, “mysql Client Tips”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
sql_slave_skip_counter
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
sql_warnings
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ssl
</h3>
<dl>
<dt>
<a class="xref" href="encrypted-connection-protocols-ciphers.html" title="8.3.2 Encrypted Connection TLS Protocols and Ciphers">
Section 8.3.2, “Encrypted Connection TLS Protocols and Ciphers”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ssl_ca
</h3>
<dl>
<dt>
<a class="xref" href="connection-options.html" title="6.2.3 Command Options for Connecting to the Server">
Section 6.2.3, “Command Options for Connecting to the Server”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="using-encrypted-connections.html" title="8.3.1 Configuring MySQL to Use Encrypted Connections">
Section 8.3.1, “Configuring MySQL to Use Encrypted Connections”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="creating-ssl-rsa-files-using-mysql.html" title="8.3.3.1 Creating SSL and RSA Certificates and Keys using MySQL">
Section 8.3.3.1, “Creating SSL and RSA Certificates and Keys using MySQL”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="creating-ssl-files-using-openssl.html" title="8.3.3.2 Creating SSL Certificates and Keys Using openssl">
Section 8.3.3.2, “Creating SSL Certificates and Keys Using openssl”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-secure-socket-layer-support-ssl.html" title="20.6.2 Securing Group Communication Connections with Secure Socket Layer (SSL)">
Section 20.6.2, “Securing Group Communication Connections with Secure Socket Layer (SSL)”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-status-variables.html" title="7.1.10 Server Status Variables">
Section 7.1.10, “Server Status Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-encrypted-connections.html" title="19.3.1 Setting Up Replication to Use Encrypted Connections">
Section 19.3.1, “Setting Up Replication to Use Encrypted Connections”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="x-plugin-options-system-variables.html" title="22.5.6.2 X Plugin Options and System Variables">
Section 22.5.6.2, “X Plugin Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ssl_capath
</h3>
<dl>
<dt>
<a class="xref" href="connection-options.html" title="6.2.3 Command Options for Connecting to the Server">
Section 6.2.3, “Command Options for Connecting to the Server”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="using-encrypted-connections.html" title="8.3.1 Configuring MySQL to Use Encrypted Connections">
Section 8.3.1, “Configuring MySQL to Use Encrypted Connections”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-secure-socket-layer-support-ssl.html" title="20.6.2 Securing Group Communication Connections with Secure Socket Layer (SSL)">
Section 20.6.2, “Securing Group Communication Connections with Secure Socket Layer (SSL)”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-status-variables.html" title="7.1.10 Server Status Variables">
Section 7.1.10, “Server Status Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-encrypted-connections.html" title="19.3.1 Setting Up Replication to Use Encrypted Connections">
Section 19.3.1, “Setting Up Replication to Use Encrypted Connections”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="x-plugin-options-system-variables.html" title="22.5.6.2 X Plugin Options and System Variables">
Section 22.5.6.2, “X Plugin Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ssl_cert
</h3>
<dl>
<dt>
<a class="xref" href="connection-options.html" title="6.2.3 Command Options for Connecting to the Server">
Section 6.2.3, “Command Options for Connecting to the Server”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="using-encrypted-connections.html" title="8.3.1 Configuring MySQL to Use Encrypted Connections">
Section 8.3.1, “Configuring MySQL to Use Encrypted Connections”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="creating-ssl-rsa-files-using-mysql.html" title="8.3.3.1 Creating SSL and RSA Certificates and Keys using MySQL">
Section 8.3.3.1, “Creating SSL and RSA Certificates and Keys using MySQL”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="creating-ssl-files-using-openssl.html" title="8.3.3.2 Creating SSL Certificates and Keys Using openssl">
Section 8.3.3.2, “Creating SSL Certificates and Keys Using openssl”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="encrypted-connection-protocols-ciphers.html" title="8.3.2 Encrypted Connection TLS Protocols and Ciphers">
Section 8.3.2, “Encrypted Connection TLS Protocols and Ciphers”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-secure-socket-layer-support-ssl.html" title="20.6.2 Securing Group Communication Connections with Secure Socket Layer (SSL)">
Section 20.6.2, “Securing Group Communication Connections with Secure Socket Layer (SSL)”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-status-variables.html" title="7.1.10 Server Status Variables">
Section 7.1.10, “Server Status Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-encrypted-connections.html" title="19.3.1 Setting Up Replication to Use Encrypted Connections">
Section 19.3.1, “Setting Up Replication to Use Encrypted Connections”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="x-plugin-options-system-variables.html" title="22.5.6.2 X Plugin Options and System Variables">
Section 22.5.6.2, “X Plugin Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ssl_cipher
</h3>
<dl>
<dt>
<a class="xref" href="connection-options.html" title="6.2.3 Command Options for Connecting to the Server">
Section 6.2.3, “Command Options for Connecting to the Server”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="using-encrypted-connections.html" title="8.3.1 Configuring MySQL to Use Encrypted Connections">
Section 8.3.1, “Configuring MySQL to Use Encrypted Connections”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="encrypted-connection-protocols-ciphers.html" title="8.3.2 Encrypted Connection TLS Protocols and Ciphers">
Section 8.3.2, “Encrypted Connection TLS Protocols and Ciphers”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-secure-socket-layer-support-ssl.html" title="20.6.2 Securing Group Communication Connections with Secure Socket Layer (SSL)">
Section 20.6.2, “Securing Group Communication Connections with Secure Socket Layer (SSL)”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-status-variables.html" title="7.1.10 Server Status Variables">
Section 7.1.10, “Server Status Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="x-plugin-options-system-variables.html" title="22.5.6.2 X Plugin Options and System Variables">
Section 22.5.6.2, “X Plugin Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ssl_crl
</h3>
<dl>
<dt>
<a class="xref" href="connection-options.html" title="6.2.3 Command Options for Connecting to the Server">
Section 6.2.3, “Command Options for Connecting to the Server”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="using-encrypted-connections.html" title="8.3.1 Configuring MySQL to Use Encrypted Connections">
Section 8.3.1, “Configuring MySQL to Use Encrypted Connections”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-secure-socket-layer-support-ssl.html" title="20.6.2 Securing Group Communication Connections with Secure Socket Layer (SSL)">
Section 20.6.2, “Securing Group Communication Connections with Secure Socket Layer (SSL)”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-status-variables.html" title="7.1.10 Server Status Variables">
Section 7.1.10, “Server Status Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="x-plugin-options-system-variables.html" title="22.5.6.2 X Plugin Options and System Variables">
Section 22.5.6.2, “X Plugin Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ssl_crlpath
</h3>
<dl>
<dt>
<a class="xref" href="connection-options.html" title="6.2.3 Command Options for Connecting to the Server">
Section 6.2.3, “Command Options for Connecting to the Server”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="using-encrypted-connections.html" title="8.3.1 Configuring MySQL to Use Encrypted Connections">
Section 8.3.1, “Configuring MySQL to Use Encrypted Connections”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-secure-socket-layer-support-ssl.html" title="20.6.2 Securing Group Communication Connections with Secure Socket Layer (SSL)">
Section 20.6.2, “Securing Group Communication Connections with Secure Socket Layer (SSL)”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-status-variables.html" title="7.1.10 Server Status Variables">
Section 7.1.10, “Server Status Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="x-plugin-options-system-variables.html" title="22.5.6.2 X Plugin Options and System Variables">
Section 22.5.6.2, “X Plugin Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ssl_fips_mode
</h3>
<dl>
<dt>
<a class="xref" href="connection-options.html" title="6.2.3 Command Options for Connecting to the Server">
Section 6.2.3, “Command Options for Connecting to the Server”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="fips-mode.html" title="8.8 FIPS Support">
Section 8.8, “FIPS Support”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ssl_key
</h3>
<dl>
<dt>
<a class="xref" href="connection-options.html" title="6.2.3 Command Options for Connecting to the Server">
Section 6.2.3, “Command Options for Connecting to the Server”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="using-encrypted-connections.html" title="8.3.1 Configuring MySQL to Use Encrypted Connections">
Section 8.3.1, “Configuring MySQL to Use Encrypted Connections”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="creating-ssl-rsa-files-using-mysql.html" title="8.3.3.1 Creating SSL and RSA Certificates and Keys using MySQL">
Section 8.3.3.1, “Creating SSL and RSA Certificates and Keys using MySQL”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="creating-ssl-files-using-openssl.html" title="8.3.3.2 Creating SSL Certificates and Keys Using openssl">
Section 8.3.3.2, “Creating SSL Certificates and Keys Using openssl”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-secure-socket-layer-support-ssl.html" title="20.6.2 Securing Group Communication Connections with Secure Socket Layer (SSL)">
Section 20.6.2, “Securing Group Communication Connections with Secure Socket Layer (SSL)”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-status-variables.html" title="7.1.10 Server Status Variables">
Section 7.1.10, “Server Status Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-encrypted-connections.html" title="19.3.1 Setting Up Replication to Use Encrypted Connections">
Section 19.3.1, “Setting Up Replication to Use Encrypted Connections”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="x-plugin-options-system-variables.html" title="22.5.6.2 X Plugin Options and System Variables">
Section 22.5.6.2, “X Plugin Options and System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ssl_session_cache_mode
</h3>
<dl>
<dt>
<a class="xref" href="reusing-ssl-sessions.html" title="8.3.5 Reusing SSL Sessions">
Section 8.3.5, “Reusing SSL Sessions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-status-variables.html" title="7.1.10 Server Status Variables">
Section 7.1.10, “Server Status Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
ssl_session_cache_timeout
</h3>
<dl>
<dt>
<a class="xref" href="reusing-ssl-sessions.html" title="8.3.5 Reusing SSL Sessions">
Section 8.3.5, “Reusing SSL Sessions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
statement_id
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
stored_program_cache
</h3>
<dl>
<dt>
<a class="xref" href="statement-caching.html" title="10.10.3 Caching of Prepared Statements and Stored Programs">
Section 10.10.3, “Caching of Prepared Statements and Stored Programs”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="data-dictionary-object-cache.html" title="16.4 Dictionary Object Cache">
Section 16.4, “Dictionary Object Cache”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
stored_program_definition_cache
</h3>
<dl>
<dt>
<a class="xref" href="data-dictionary-object-cache.html" title="16.4 Dictionary Object Cache">
Section 16.4, “Dictionary Object Cache”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
super_read_only
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-adding-instances.html#group-replication-adding-a-second-instance" title="20.2.1.6.1 Adding a Second Instance">
Section 20.2.1.6.1, “Adding a Second Instance”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="events-configuration.html" title="27.4.2 Event Scheduler Configuration">
Section 27.4.2, “Event Scheduler Configuration”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-responses-failure-exit.html" title="20.7.7.4 Exit Action">
Section 20.7.7.4, “Exit Action”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="flush.html" title="15.7.8.3 FLUSH Statement">
Section 15.7.8.3, “FLUSH Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-online-upgrade-methods.html" title="20.8.3.3 Group Replication Online Upgrade Methods">
Section 20.8.3.3, “Group Replication Online Upgrade Methods”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-server-states.html" title="20.4.2 Group Replication Server States">
Section 20.4.2, “Group Replication Server States”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-system-variables.html" title="20.9.1 Group Replication System Variables">
Section 20.9.1, “Group Replication System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-online-upgrade-considerations.html" title="20.8.3.1 Online Upgrade Considerations">
Section 20.8.3.1, “Online Upgrade Considerations”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-schema-optimization.html" title="10.2.3 Optimizing INFORMATION_SCHEMA Queries">
Section 10.2.3, “Optimizing INFORMATION_SCHEMA Queries”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-single-primary-mode.html" title="20.1.3.1 Single-Primary Mode">
Section 20.1.3.1, “Single-Primary Mode”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="start-group-replication.html" title="15.4.3.1 START GROUP_REPLICATION Statement">
Section 15.4.3.1, “START GROUP_REPLICATION Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="stop-group-replication.html" title="15.4.3.2 STOP GROUP_REPLICATION Statement">
Section 15.4.3.2, “STOP GROUP_REPLICATION Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-upgrading-member.html" title="20.8.3.2 Upgrading a Group Replication Member">
Section 20.8.3.2, “Upgrading a Group Replication Member”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
sync_binlog
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-binary-log.html" title="19.1.6.4 Binary Logging Options and Variables">
Section 19.1.6.4, “Binary Logging Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-gtids-auto-positioning.html" title="19.1.3.3 GTID Auto-Positioning">
Section 19.1.3.3, “GTID Auto-Positioning”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-acid.html" title="17.2 InnoDB and the ACID Model">
Section 17.2, “InnoDB and the ACID Model”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-shutdowns.html" title="19.5.1.28 Replication and Source or Replica Shutdowns">
Section 19.5.1.28, “Replication and Source or Replica Shutdowns”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log.html" title="7.4.4 The Binary Log">
Section 7.4.4, “The Binary Log”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
sync_master_info
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
sync_relay_log
</h3>
<dl>
<dt>
<a class="xref" href="replication-solutions-unexpected-replica-halt.html" title="19.4.2 Handling an Unexpected Halt of a Replica">
Section 19.4.2, “Handling an Unexpected Halt of a Replica”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
sync_relay_log_info
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-shutdowns.html" title="19.5.1.28 Replication and Source or Replica Shutdowns">
Section 19.5.1.28, “Replication and Source or Replica Shutdowns”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
sync_source_info
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
syseventlog
</h3>
<dl>
<dt>
<a class="xref" href="error-log-syslog.html" title="7.4.2.8 Error Logging to the System Log">
Section 7.4.2.8, “Error Logging to the System Log”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
system_time_zone
</h3>
<dl>
<dt>
<a class="xref" href="time-zone-support.html" title="7.1.15 MySQL Server Time Zone Support">
Section 7.1.15, “MySQL Server Time Zone Support”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-timezone.html" title="19.5.1.33 Replication and Time Zones">
Section 19.5.1.33, “Replication and Time Zones”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-options.html" title="7.1.7 Server Command Options">
Section 7.1.7, “Server Command Options”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<a name="sysvar-index-T">
</a>
<h3 class="title">
T
</h3>
<p>
[
<a class="link" href="dynindex-sysvar.html#sysvar-index-top">
index top
</a>
]
</p>
<dl>
<dt>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
table_definition_cache
</h3>
<dl>
<dt>
<a class="xref" href="data-dictionary-object-cache.html" title="16.4 Dictionary Object Cache">
Section 16.4, “Dictionary Object Cache”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="memory-use.html" title="10.12.3.1 How MySQL Uses Memory">
Section 10.12.3.1, “How MySQL Uses Memory”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
table_encryption_privilege_check
</h3>
<dl>
<dt>
<a class="xref" href="alter-database.html" title="15.1.2 ALTER DATABASE Statement">
Section 15.1.2, “ALTER DATABASE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="alter-table.html" title="15.1.9 ALTER TABLE Statement">
Section 15.1.9, “ALTER TABLE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="alter-tablespace.html" title="15.1.10 ALTER TABLESPACE Statement">
Section 15.1.10, “ALTER TABLESPACE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="create-database.html" title="15.1.12 CREATE DATABASE Statement">
Section 15.1.12, “CREATE DATABASE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="create-table.html" title="15.1.20 CREATE TABLE Statement">
Section 15.1.20, “CREATE TABLE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="create-tablespace.html" title="15.1.21 CREATE TABLESPACE Statement">
Section 15.1.21, “CREATE TABLESPACE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-data-encryption.html" title="17.13 InnoDB Data-at-Rest Encryption">
Section 17.13, “InnoDB Data-at-Rest Encryption”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-privilege-checks-account.html" title="19.3.3.1 Privileges For The Replication PRIVILEGE_CHECKS_USER Account">
Section 19.3.3.1, “Privileges For The Replication PRIVILEGE_CHECKS_USER Account”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="privileges-provided.html" title="8.2.2 Privileges Provided by MySQL">
Section 8.2.2, “Privileges Provided by MySQL”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="rename-table.html" title="15.1.36 RENAME TABLE Statement">
Section 15.1.36, “RENAME TABLE Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
table_open_cache
</h3>
<dl>
<dt>
<a class="xref" href="not-enough-file-handles.html" title="B.3.2.16 File Not Found and Similar Errors">
Section B.3.2.16, “File Not Found and Similar Errors”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="general-thread-states.html" title="10.14.3 General Thread States">
Section 10.14.3, “General Thread States”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="table-cache.html" title="10.4.3.1 How MySQL Opens and Closes Tables">
Section 10.4.3.1, “How MySQL Opens and Closes Tables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="memory-use.html" title="10.12.3.1 How MySQL Uses Memory">
Section 10.12.3.1, “How MySQL Uses Memory”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-status-variables.html" title="7.1.10 Server Status Variables">
Section 7.1.10, “Server Status Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
table_open_cache_instances
</h3>
<dl>
<dt>
<a class="xref" href="log-destinations.html" title="7.4.1 Selecting General Query Log and Slow Query Log Output Destinations">
Section 7.4.1, “Selecting General Query Log and Slow Query Log Output Destinations”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-status-variables.html" title="7.1.10 Server Status Variables">
Section 7.1.10, “Server Status Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
tablespace_definition_cache
</h3>
<dl>
<dt>
<a class="xref" href="data-dictionary-object-cache.html" title="16.4 Dictionary Object Cache">
Section 16.4, “Dictionary Object Cache”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
telemetry
</h3>
<dl>
<dt>
<a class="xref" href="telemetry-metrics-configuration.html" title="35.4.1 Configuring Metrics Telemetry">
Section 35.4.1, “Configuring Metrics Telemetry”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="telemetry-trace-configuration.html" title="35.3.1 Configuring Trace Telemetry">
Section 35.3.1, “Configuring Trace Telemetry”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
temptable_max_mmap
</h3>
<dl>
<dt>
<a class="xref" href="internal-temporary-tables.html" title="10.4.4 Internal Temporary Table Use in MySQL">
Section 10.4.4, “Internal Temporary Table Use in MySQL”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
temptable_max_ram
</h3>
<dl>
<dt>
<a class="xref" href="internal-temporary-tables.html" title="10.4.4 Internal Temporary Table Use in MySQL">
Section 10.4.4, “Internal Temporary Table Use in MySQL”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
temptable_use_mmap
</h3>
<dl>
<dt>
<a class="xref" href="internal-temporary-tables.html" title="10.4.4 Internal Temporary Table Use in MySQL">
Section 10.4.4, “Internal Temporary Table Use in MySQL”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-status-variables.html" title="7.1.10 Server Status Variables">
Section 7.1.10, “Server Status Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
terminology_use_previous
</h3>
<dl>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replica-io-thread-states.html" title="10.14.5 Replication I/O (Receiver) Thread States">
Section 10.14.5, “Replication I/O (Receiver) Thread States”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="source-thread-states.html" title="10.14.4 Replication Source Thread States">
Section 10.14.4, “Replication Source Thread States”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replica-sql-thread-states.html" title="10.14.6 Replication SQL Thread States">
Section 10.14.6, “Replication SQL Thread States”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
thread_cache_size
</h3>
<dl>
<dt>
<a class="xref" href="connection-interfaces.html" title="7.1.12.1 Connection Interfaces">
Section 7.1.12.1, “Connection Interfaces”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="using-gdb-on-mysqld.html" title="7.9.1.4 Debugging mysqld under gdb">
Section 7.9.1.4, “Debugging mysqld under gdb”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-status-variables.html" title="7.1.10 Server Status Variables">
Section 7.1.10, “Server Status Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
thread_handling
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="thread-pool-elements.html" title="7.6.3.1 Thread Pool Elements">
Section 7.6.3.1, “Thread Pool Elements”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
thread_pool_algorithm
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-tp-thread-group-state-table.html" title="29.12.16.2 The tp_thread_group_state Table">
Section 29.12.16.2, “The tp_thread_group_state Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="thread-pool-operation.html" title="7.6.3.3 Thread Pool Operation">
Section 7.6.3.3, “Thread Pool Operation”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="thread-pool-tuning.html" title="7.6.3.4 Thread Pool Tuning">
Section 7.6.3.4, “Thread Pool Tuning”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
thread_pool_dedicated_listeners
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="thread-pool-operation.html" title="7.6.3.3 Thread Pool Operation">
Section 7.6.3.3, “Thread Pool Operation”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
thread_pool_high_priority_connection
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="thread-pool-operation.html" title="7.6.3.3 Thread Pool Operation">
Section 7.6.3.3, “Thread Pool Operation”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
thread_pool_longrun_trx_limit
</h3>
<dl>
<dt>
<a class="xref" href="privileges-provided.html" title="8.2.2 Privileges Provided by MySQL">
Section 8.2.2, “Privileges Provided by MySQL”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="thread-pool-operation.html" title="7.6.3.3 Thread Pool Operation">
Section 7.6.3.3, “Thread Pool Operation”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
thread_pool_max_active_query_threads
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="thread-pool-operation.html" title="7.6.3.3 Thread Pool Operation">
Section 7.6.3.3, “Thread Pool Operation”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
thread_pool_max_transactions_limit
</h3>
<dl>
<dt>
<a class="xref" href="privileges-provided.html" title="8.2.2 Privileges Provided by MySQL">
Section 8.2.2, “Privileges Provided by MySQL”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="thread-pool-operation.html" title="7.6.3.3 Thread Pool Operation">
Section 7.6.3.3, “Thread Pool Operation”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="thread-pool-tuning.html" title="7.6.3.4 Thread Pool Tuning">
Section 7.6.3.4, “Thread Pool Tuning”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
thread_pool_max_unused_threads
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="thread-pool-operation.html" title="7.6.3.3 Thread Pool Operation">
Section 7.6.3.3, “Thread Pool Operation”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
thread_pool_prio_kickup_timer
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-tp-thread-group-state-table.html" title="29.12.16.2 The tp_thread_group_state Table">
Section 29.12.16.2, “The tp_thread_group_state Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-tp-thread-group-stats-table.html" title="29.12.16.3 The tp_thread_group_stats Table">
Section 29.12.16.3, “The tp_thread_group_stats Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="thread-pool-operation.html" title="7.6.3.3 Thread Pool Operation">
Section 7.6.3.3, “Thread Pool Operation”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="thread-pool-tuning.html" title="7.6.3.4 Thread Pool Tuning">
Section 7.6.3.4, “Thread Pool Tuning”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
thread_pool_query_threads_per_group
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="thread-pool-operation.html" title="7.6.3.3 Thread Pool Operation">
Section 7.6.3.3, “Thread Pool Operation”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="thread-pool-tuning.html" title="7.6.3.4 Thread Pool Tuning">
Section 7.6.3.4, “Thread Pool Tuning”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
thread_pool_size
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="thread-pool-operation.html" title="7.6.3.3 Thread Pool Operation">
Section 7.6.3.3, “Thread Pool Operation”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
thread_pool_stall_limit
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-tp-thread-group-state-table.html" title="29.12.16.2 The tp_thread_group_state Table">
Section 29.12.16.2, “The tp_thread_group_state Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="performance-schema-tp-thread-group-stats-table.html" title="29.12.16.3 The tp_thread_group_stats Table">
Section 29.12.16.3, “The tp_thread_group_stats Table”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="thread-pool-operation.html" title="7.6.3.3 Thread Pool Operation">
Section 7.6.3.3, “Thread Pool Operation”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="thread-pool-tuning.html" title="7.6.3.4 Thread Pool Tuning">
Section 7.6.3.4, “Thread Pool Tuning”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
thread_pool_transaction_delay
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="thread-pool-operation.html" title="7.6.3.3 Thread Pool Operation">
Section 7.6.3.3, “Thread Pool Operation”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
thread_stack
</h3>
<dl>
<dt>
<a class="xref" href="connection-interfaces.html" title="7.1.12.1 Connection Interfaces">
Section 7.1.12.1, “Connection Interfaces”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="memory-use.html" title="10.12.3.1 How MySQL Uses Memory">
Section 10.12.3.1, “How MySQL Uses Memory”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="stored-routines-syntax.html" title="27.2.1 Stored Routine Syntax">
Section 27.2.1, “Stored Routine Syntax”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="window-function-restrictions.html" title="14.20.5 Window Function Restrictions">
Section 14.20.5, “Window Function Restrictions”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
time_zone
</h3>
<dl>
<dt>
<a class="xref" href="create-event.html" title="15.1.13 CREATE EVENT Statement">
Section 15.1.13, “CREATE EVENT Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="date-and-time-functions.html" title="14.7 Date and Time Functions">
Section 14.7, “Date and Time Functions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="date-and-time-literals.html" title="11.1.3 Date and Time Literals">
Section 11.1.3, “Date and Time Literals”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="events-metadata.html" title="27.4.4 Event Metadata">
Section 27.4.4, “Event Metadata”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log-mixed.html" title="7.4.4.3 Mixed Binary Logging Format">
Section 7.4.4.3, “Mixed Binary Logging Format”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="time-zone-support.html" title="7.1.15 MySQL Server Time Zone Support">
Section 7.1.15, “MySQL Server Time Zone Support”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-timezone.html" title="19.5.1.33 Replication and Time Zones">
Section 19.5.1.33, “Replication and Time Zones”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-variables.html" title="19.5.1.39 Replication and Variables">
Section 19.5.1.39, “Replication and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-options.html" title="7.1.7 Server Command Options">
Section 7.1.7, “Server Command Options”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="datetime.html" title="13.2.2 The DATE, DATETIME, and TIMESTAMP Types">
Section 13.2.2, “The DATE, DATETIME, and TIMESTAMP Types”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="query-log.html" title="7.4.3 The General Query Log">
Section 7.4.3, “The General Query Log”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="slow-query-log.html" title="7.4.5 The Slow Query Log">
Section 7.4.5, “The Slow Query Log”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
timestamp
</h3>
<dl>
<dt>
<a class="xref" href="federated-usagenotes.html" title="18.8.3 FEDERATED Storage Engine Notes and Tips">
Section 18.8.3, “FEDERATED Storage Engine Notes and Tips”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log-mixed.html" title="7.4.4.3 Mixed Binary Logging Format">
Section 7.4.4.3, “Mixed Binary Logging Format”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-variables.html" title="19.5.1.39 Replication and Variables">
Section 19.5.1.39, “Replication and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
tls
</h3>
<dl>
<dt>
<a class="xref" href="encrypted-connection-protocols-ciphers.html" title="8.3.2 Encrypted Connection TLS Protocols and Ciphers">
Section 8.3.2, “Encrypted Connection TLS Protocols and Ciphers”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="faqs-security.html" title="A.9 MySQL 8.4 FAQ: Security">
Section A.9, “MySQL 8.4 FAQ: Security”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
tls_certificates_enforced_validation
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
tls_ciphersuites
</h3>
<dl>
<dt>
<a class="xref" href="connection-options.html" title="6.2.3 Command Options for Connecting to the Server">
Section 6.2.3, “Command Options for Connecting to the Server”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="using-encrypted-connections.html" title="8.3.1 Configuring MySQL to Use Encrypted Connections">
Section 8.3.1, “Configuring MySQL to Use Encrypted Connections”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="encrypted-connection-protocols-ciphers.html" title="8.3.2 Encrypted Connection TLS Protocols and Ciphers">
Section 8.3.2, “Encrypted Connection TLS Protocols and Ciphers”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-secure-socket-layer-support-ssl.html" title="20.6.2 Securing Group Communication Connections with Secure Socket Layer (SSL)">
Section 20.6.2, “Securing Group Communication Connections with Secure Socket Layer (SSL)”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-status-variables.html" title="7.1.10 Server Status Variables">
Section 7.1.10, “Server Status Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
tls_version
</h3>
<dl>
<dt>
<a class="xref" href="connection-options.html" title="6.2.3 Command Options for Connecting to the Server">
Section 6.2.3, “Command Options for Connecting to the Server”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="using-encrypted-connections.html" title="8.3.1 Configuring MySQL to Use Encrypted Connections">
Section 8.3.1, “Configuring MySQL to Use Encrypted Connections”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="source-ssl-library-configuration.html" title="2.8.6 Configuring SSL Library Support">
Section 2.8.6, “Configuring SSL Library Support”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="encrypted-connection-protocols-ciphers.html" title="8.3.2 Encrypted Connection TLS Protocols and Ciphers">
Section 8.3.2, “Encrypted Connection TLS Protocols and Ciphers”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-secure-socket-layer-support-ssl.html" title="20.6.2 Securing Group Communication Connections with Secure Socket Layer (SSL)">
Section 20.6.2, “Securing Group Communication Connections with Secure Socket Layer (SSL)”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-status-variables.html" title="7.1.10 Server Status Variables">
Section 7.1.10, “Server Status Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-encrypted-connections.html" title="19.3.1 Setting Up Replication to Use Encrypted Connections">
Section 19.3.1, “Setting Up Replication to Use Encrypted Connections”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="x-plugin-encrypted-connections.html" title="22.5.3 Using Encrypted Connections with X Plugin">
Section 22.5.3, “Using Encrypted Connections with X Plugin”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
tmp_table_size
</h3>
<dl>
<dt>
<a class="xref" href="memory-use.html" title="10.12.3.1 How MySQL Uses Memory">
Section 10.12.3.1, “How MySQL Uses Memory”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="internal-temporary-tables.html" title="10.4.4 Internal Temporary Table Use in MySQL">
Section 10.4.4, “Internal Temporary Table Use in MySQL”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="cursor-restrictions.html" title="15.6.6.5 Restrictions on Server-Side Cursors">
Section 15.6.6.5, “Restrictions on Server-Side Cursors”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-configurator-workflow-server.html#server-type-network" title="2.3.2.1.2 Type and Networking">
Section 2.3.2.1.2, “Type and Networking”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
tmpdir
</h3>
<dl>
<dt>
<a class="xref" href="replication-solutions-backups-rawdata.html" title="19.4.1.2 Backing Up Raw Data from a Replica">
Section 19.4.1.2, “Backing Up Raw Data from a Replica”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="cannot-create.html" title="B.3.2.11 Can't create/write to file">
Section B.3.2.11, “Can't create/write to file”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="backup-methods.html" title="9.2 Database Backup Methods">
Section 9.2, “Database Backup Methods”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="internal-temporary-tables.html" title="10.4.4 Internal Temporary Table Use in MySQL">
Section 10.4.4, “Internal Temporary Table Use in MySQL”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="source-configuration-options.html" title="2.8.7 MySQL Source-Configuration Options">
Section 2.8.7, “MySQL Source-Configuration Options”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-online-ddl-failure-conditions.html" title="17.12.7 Online DDL Failure Conditions">
Section 17.12.7, “Online DDL Failure Conditions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-online-ddl-space-requirements.html" title="17.12.3 Online DDL Space Requirements">
Section 17.12.3, “Online DDL Space Requirements”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="order-by-optimization.html" title="10.2.1.16 ORDER BY Optimization">
Section 10.2.1.16, “ORDER BY Optimization”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-options-replica.html" title="19.1.6.3 Replica Server Options and Variables">
Section 19.1.6.3, “Replica Server Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="mysql-nutshell.html" title="1.4 What Is New in MySQL 8.4 since MySQL 8.0">
Section 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
transaction_alloc_block_size
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
transaction_allow_batching
</h3>
<dl>
<dt>
<a class="xref" href="mysql-cluster-options-variables.html#mysql-cluster-system-variables" title="25.4.3.9.2 NDB Cluster System Variables">
Section 25.4.3.9.2, “NDB Cluster System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
transaction_isolation
</h3>
<dl>
<dt>
<a class="xref" href="server-options.html" title="7.1.7 Server Command Options">
Section 7.1.7, “Server Command Options”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="session-state-tracking.html" title="7.1.18 Server Tracking of Client Session State">
Section 7.1.18, “Server Tracking of Client Session State”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="set-transaction.html" title="15.3.7 SET TRANSACTION Statement">
Section 15.3.7, “SET TRANSACTION Statement”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
transaction_prealloc_size
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
transaction_read_only
</h3>
<dl>
<dt>
<a class="xref" href="information-schema-optimization.html" title="10.2.3 Optimizing INFORMATION_SCHEMA Queries">
Section 10.2.3, “Optimizing INFORMATION_SCHEMA Queries”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-options.html" title="7.1.7 Server Command Options">
Section 7.1.7, “Server Command Options”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="session-state-tracking.html" title="7.1.18 Server Tracking of Client Session State">
Section 7.1.18, “Server Tracking of Client Session State”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="set-transaction.html" title="15.3.7 SET TRANSACTION Statement">
Section 15.3.7, “SET TRANSACTION Statement”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<a name="sysvar-index-U">
</a>
<h3 class="title">
U
</h3>
<p>
[
<a class="link" href="dynindex-sysvar.html#sysvar-index-top">
index top
</a>
]
</p>
<dl>
<dt>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
unique_checks
</h3>
<dl>
<dt>
<a class="xref" href="converting-tables-to-innodb.html" title="17.6.1.5 Converting Tables from MyISAM to InnoDB">
Section 17.6.1.5, “Converting Tables from MyISAM to InnoDB”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log-mixed.html" title="7.4.4.3 Mixed Binary Logging Format">
Section 7.4.4.3, “Mixed Binary Logging Format”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="replication-features-variables.html" title="19.5.1.39 Replication and Variables">
Section 19.5.1.39, “Replication and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="binary-log.html" title="7.4.4 The Binary Log">
Section 7.4.4, “The Binary Log”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
updatable_views_with_limit
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="view-updatability.html" title="27.5.3 Updatable and Insertable Views">
Section 27.5.3, “Updatable and Insertable Views”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
use_secondary_engine
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<a name="sysvar-index-V">
</a>
<h3 class="title">
V
</h3>
<p>
[
<a class="link" href="dynindex-sysvar.html#sysvar-index-top">
index top
</a>
]
</p>
<dl>
<dt>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
validate_password
</h3>
<dl>
<dt>
<a class="xref" href="encryption-functions.html" title="14.13 Encryption and Compression Functions">
Section 14.13, “Encryption and Compression Functions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="validate-password-options-variables.html" title="8.4.3.2 Password Validation Options and Variables">
Section 8.4.3.2, “Password Validation Options and Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="validate-password.html" title="8.4.3 The Password Validation Component">
Section 8.4.3, “The Password Validation Component”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
validate_password_check_user_name
</h3>
<dl>
<dt>
<a class="xref" href="validate-password-options-variables.html" title="8.4.3.2 Password Validation Options and Variables">
Section 8.4.3.2, “Password Validation Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
validate_password_dictionary_file
</h3>
<dl>
<dt>
<a class="xref" href="validate-password-options-variables.html" title="8.4.3.2 Password Validation Options and Variables">
Section 8.4.3.2, “Password Validation Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
validate_password_length
</h3>
<dl>
<dt>
<a class="xref" href="validate-password-options-variables.html" title="8.4.3.2 Password Validation Options and Variables">
Section 8.4.3.2, “Password Validation Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
validate_password_mixed_case_count
</h3>
<dl>
<dt>
<a class="xref" href="validate-password-options-variables.html" title="8.4.3.2 Password Validation Options and Variables">
Section 8.4.3.2, “Password Validation Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
validate_password_number_count
</h3>
<dl>
<dt>
<a class="xref" href="validate-password-options-variables.html" title="8.4.3.2 Password Validation Options and Variables">
Section 8.4.3.2, “Password Validation Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
validate_password_policy
</h3>
<dl>
<dt>
<a class="xref" href="validate-password-options-variables.html" title="8.4.3.2 Password Validation Options and Variables">
Section 8.4.3.2, “Password Validation Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
validate_password_special_char_count
</h3>
<dl>
<dt>
<a class="xref" href="validate-password-options-variables.html" title="8.4.3.2 Password Validation Options and Variables">
Section 8.4.3.2, “Password Validation Options and Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
version
</h3>
<dl>
<dt>
<a class="xref" href="audit-log-file-formats.html" title="8.4.5.4 Audit Log File Formats">
Section 8.4.5.4, “Audit Log File Formats”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="information-functions.html" title="14.15 Information Functions">
Section 14.15, “Information Functions”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="innodb-parameters.html" title="17.14 InnoDB Startup Options and System Variables">
Section 17.14, “InnoDB Startup Options and System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
version_comment
</h3>
<dl>
<dt>
<a class="xref" href="source-configuration-options.html" title="2.8.7 MySQL Source-Configuration Options">
Section 2.8.7, “MySQL Source-Configuration Options”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="show-variables.html" title="15.7.7.41 SHOW VARIABLES Statement">
Section 15.7.7.41, “SHOW VARIABLES Statement”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
version_compile_machine
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
version_compile_os
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
version_compile_zlib
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
version_tokens_session
</h3>
<dl>
<dt>
<a class="xref" href="version-tokens-usage.html" title="7.6.6.3 Using Version Tokens">
Section 7.6.6.3, “Using Version Tokens”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="version-tokens-reference.html" title="7.6.6.4 Version Tokens Reference">
Section 7.6.6.4, “Version Tokens Reference”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
version_tokens_session_number
</h3>
<dl>
<dt>
<a class="xref" href="version-tokens-reference.html" title="7.6.6.4 Version Tokens Reference">
Section 7.6.6.4, “Version Tokens Reference”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<a name="sysvar-index-W">
</a>
<h3 class="title">
W
</h3>
<p>
[
<a class="link" href="dynindex-sysvar.html#sysvar-index-top">
index top
</a>
]
</p>
<dl>
<dt>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
wait_timeout
</h3>
<dl>
<dt>
<a class="xref" href="communication-errors.html" title="B.3.2.9 Communication Errors and Aborted Connections">
Section B.3.2.9, “Communication Errors and Aborted Connections”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="group-replication-configuring-consistency-guarantees.html" title="20.5.3.2 Configuring Transaction Consistency Guarantees">
Section 20.5.3.2, “Configuring Transaction Consistency Guarantees”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="gone-away.html" title="B.3.2.7 MySQL server has gone away">
Section B.3.2.7, “MySQL server has gone away”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="clone-plugin-failure-handling.html" title="7.6.7.9 Remote Cloning Operation Failure Handling">
Section 7.6.7.9, “Remote Cloning Operation Failure Handling”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
warning_count
</h3>
<dl>
<dt>
<a class="xref" href="error-interfaces.html" title="B.2 Error Information Interfaces">
Section B.2, “Error Information Interfaces”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="sql-prepared-statements.html" title="15.5 Prepared Statements">
Section 15.5, “Prepared Statements”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="show-errors.html" title="15.7.7.18 SHOW ERRORS Statement">
Section 15.7.7.18, “SHOW ERRORS Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="show-warnings.html" title="15.7.7.42 SHOW WARNINGS Statement">
Section 15.7.7.42, “SHOW WARNINGS Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="signal.html" title="15.6.7.5 SIGNAL Statement">
Section 15.6.7.5, “SIGNAL Statement”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="diagnostics-area.html" title="15.6.7.7 The MySQL Diagnostics Area">
Section 15.6.7.7, “The MySQL Diagnostics Area”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
windowing_use_high_precision
</h3>
<dl>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="window-function-optimization.html" title="10.2.1.21 Window Function Optimization">
Section 10.2.1.21, “Window Function Optimization”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<a name="sysvar-index-X">
</a>
<h3 class="title">
X
</h3>
<p>
[
<a class="link" href="dynindex-sysvar.html#sysvar-index-top">
index top
</a>
]
</p>
<dl>
<dt>
</dt>
<dd>
</dd>
</dl>
</div>
<div class="indexdiv">
<h3 class="title">
xa_detach_on_prepare
</h3>
<dl>
<dt>
<a class="xref" href="group-replication-requirements.html" title="20.3.1 Group Replication Requirements">
Section 20.3.1, “Group Replication Requirements”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
</dt>
<dd>
</dd>
<dt>
<a class="xref" href="xa-states.html" title="15.3.8.2 XA Transaction States">
Section 15.3.8.2, “XA Transaction States”
</a>
</dt>
<dd>
</dd>
</dl>
</div>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-tp-thread-state-table.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="performance-schema-tp-thread-state-table">
</a>
29.12.16.4 The tp_thread_state Table
</h4>
</div>
</div>
</div>
<a class="indexterm" name="idm46045069698352">
</a>
<a class="indexterm" name="idm46045069696864">
</a>
<p>
The
<a class="link" href="performance-schema-tp-thread-state-table.html" title="29.12.16.4 The tp_thread_state Table">
<code class="literal">
tp_thread_state
</code>
</a>
table has one
row per thread created by the thread pool to handle
connections.
</p>
<p>
The
<a class="link" href="performance-schema-tp-thread-state-table.html" title="29.12.16.4 The tp_thread_state Table">
<code class="literal">
tp_thread_state
</code>
</a>
table has
these columns:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<code class="literal">
TP_GROUP_ID
</code>
</p>
<p>
The thread group ID.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
TP_THREAD_NUMBER
</code>
</p>
<p>
The ID of the thread within its thread group.
<code class="literal">
TP_GROUP_ID
</code>
and
<code class="literal">
TP_THREAD_NUMBER
</code>
together provide a
unique key within the table.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
PROCESS_COUNT
</code>
</p>
<p>
The 10ms interval in which the statement that uses this
thread is currently executing. 0 means no statement is
executing, 1 means it is in the first 10ms, and so forth.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
WAIT_TYPE
</code>
</p>
<p>
The type of wait for the thread.
<code class="literal">
NULL
</code>
means the thread is not blocked. Otherwise, the thread is
blocked by a call to
<code class="literal">
thd_wait_begin()
</code>
and the value specifies the type of wait. The
<code class="literal">
<em class="replaceable">
<code>
xxx
</code>
</em>
_WAIT
</code>
columns of the
<a class="link" href="performance-schema-tp-thread-group-stats-table.html" title="29.12.16.3 The tp_thread_group_stats Table">
<code class="literal">
tp_thread_group_stats
</code>
</a>
table
accumulate counts for each wait type.
</p>
<p>
The
<code class="literal">
WAIT_TYPE
</code>
value is a string that
describes the type of wait, as shown in the following
table.
</p>
<div class="table">
<a name="idm46045069677168">
</a>
<p class="title">
<b>
Table 29.4 tp_thread_state Table WAIT_TYPE Values
</b>
</p>
<div class="table-contents">
<table summary="tp_thread_state table WAIT_TYPE values. The first column is the wait type. The second column describes the wait type.">
<colgroup>
<col style="width: 35%"/>
<col style="width: 65%"/>
</colgroup>
<thead>
<tr>
<th>
Wait Type
</th>
<th>
Meaning
</th>
</tr>
</thead>
<tbody>
<tr>
<td>
<code class="literal">
THD_WAIT_SLEEP
</code>
</td>
<td>
Waiting for sleep
</td>
</tr>
<tr>
<td>
<code class="literal">
THD_WAIT_DISKIO
</code>
</td>
<td>
Waiting for Disk IO
</td>
</tr>
<tr>
<td>
<code class="literal">
THD_WAIT_ROW_LOCK
</code>
</td>
<td>
Waiting for row lock
</td>
</tr>
<tr>
<td>
<code class="literal">
THD_WAIT_GLOBAL_LOCK
</code>
</td>
<td>
Waiting for global lock
</td>
</tr>
<tr>
<td>
<code class="literal">
THD_WAIT_META_DATA_LOCK
</code>
</td>
<td>
Waiting for metadata lock
</td>
</tr>
<tr>
<td>
<code class="literal">
THD_WAIT_TABLE_LOCK
</code>
</td>
<td>
Waiting for table lock
</td>
</tr>
<tr>
<td>
<code class="literal">
THD_WAIT_USER_LOCK
</code>
</td>
<td>
Waiting for user lock
</td>
</tr>
<tr>
<td>
<code class="literal">
THD_WAIT_BINLOG
</code>
</td>
<td>
Waiting for binlog
</td>
</tr>
<tr>
<td>
<code class="literal">
THD_WAIT_GROUP_COMMIT
</code>
</td>
<td>
Waiting for group commit
</td>
</tr>
<tr>
<td>
<code class="literal">
THD_WAIT_SYNC
</code>
</td>
<td>
Waiting for fsync
</td>
</tr>
</tbody>
</table>
</div>
<div class="table-contents">
<table cellpadding="0" cellspacing="0" style="position: fixed; top: 0px; display: none; left: 431px; width: 555px;">
<thead>
<tr>
<th style="width: 193.891px;">
Wait Type
</th>
<th style="width: 360.078px;">
Meaning
</th>
</tr>
</thead>
</table>
</div>
</div>
<br class="table-break"/>
</li>
<li class="listitem">
<p>
<code class="literal">
TP_THREAD_TYPE
</code>
</p>
<p>
The type of thread. The value shown in this column is one
of
<code class="literal">
CONNECTION_HANDLER_WORKER_THREAD
</code>
,
<code class="literal">
LISTENER_WORKER_THREAD
</code>
,
<code class="literal">
QUERY_WORKER_THREAD
</code>
, or
<code class="literal">
TIMER_WORKER_THREAD
</code>
.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
THREAD_ID
</code>
</p>
<p>
This thread's unique identifier. The value is the
same as that used in the
<code class="literal">
THREAD_ID
</code>
column of the Performance Schema
<a class="link" href="performance-schema-threads-table.html" title="29.12.22.8 The threads Table">
<code class="literal">
threads
</code>
</a>
table.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
TIME_OF_ATTACH
</code>
:
</p>
<p>
Timestamp showing when the thread was attached, if
attached to a connection; otherwise
<code class="literal">
NULL
</code>
.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
MARKED_STALLED
</code>
:
</p>
<p>
This is
<code class="literal">
True
</code>
if this thread has been
marked as stalled by the stall checker thread.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
STATE
</code>
:
</p>
<p>
Possible values depend on the type of thread, as shown by
the
<code class="literal">
TP_THREAD_TYPE
</code>
column:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
For worker threads
(
<code class="literal">
QUERY_WORKER_THREAD
</code>
), this is
one of
<code class="literal">
Managing
</code>
,
<code class="literal">
Polling
</code>
,
<code class="literal">
Processing
Direct
</code>
,
<code class="literal">
Processing
Queued
</code>
,
<code class="literal">
Sleeping
Consumer
</code>
, or
<code class="literal">
Sleeping
Reserve
</code>
.
</p>
</li>
<li class="listitem">
<p>
For connection handler threads
(
<code class="literal">
CONNECTION_HANDLER_WORKER_THREAD
</code>
),
this is one of
<code class="literal">
CH Processing
</code>
,
<code class="literal">
CH Sleeping Timed
</code>
, or
<code class="literal">
CH
Sleeping Indefinite
</code>
.
</p>
</li>
<li class="listitem">
<p>
For the stall checker thread
(
<code class="literal">
TIMER_WORKER_THREAD
</code>
), this is
one of
<code class="literal">
SC Checking
</code>
,
<code class="literal">
SC
Sleeping Short
</code>
, or
<code class="literal">
SC Sleeping
Long
</code>
.
</p>
</li>
</ul>
</div>
<p>
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
EVENT_COUNT
</code>
:
</p>
<p>
The accumulated number of events processed by this thread.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
ACCUMULATED_EVENT_TIME
</code>
:
</p>
<p>
The wall clock time spent processing events.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
EXEC_COUNT
</code>
:
</p>
<p>
The accumulated number of queries (statements) passed to
the server for execution.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
ACCUMULATED_EXEC_TIME
</code>
:
</p>
<p>
The wall clock time spent processing queries by the
server.
</p>
</li>
</ul>
</div>
<p>
The
<a class="link" href="performance-schema-tp-thread-state-table.html" title="29.12.16.4 The tp_thread_state Table">
<code class="literal">
tp_thread_state
</code>
</a>
table has one
index; this is a unique index on the
<code class="literal">
TP_GROUP_ID
</code>
and
<code class="literal">
TP_THREAD_NUMBER
</code>
columns.
</p>
<p>
<a class="link" href="truncate-table.html" title="15.1.37 TRUNCATE TABLE Statement">
<code class="literal">
TRUNCATE TABLE
</code>
</a>
is not permitted
for the
<a class="link" href="performance-schema-tp-thread-state-table.html" title="29.12.16.4 The tp_thread_state Table">
<code class="literal">
tp_thread_state
</code>
</a>
table.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/mysql-tzinfo-to-sql.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="mysql-tzinfo-to-sql">
</a>
6.4.3 mysql_tzinfo_to_sql — Load the Time Zone Tables
</h3>
</div>
</div>
</div>
<a class="indexterm" name="idm46045320220784">
</a>
<a class="indexterm" name="idm46045320219872">
</a>
<p>
The
<a class="link" href="mysql-tzinfo-to-sql.html" title="6.4.3 mysql_tzinfo_to_sql — Load the Time Zone Tables">
<span class="command">
<strong>
mysql_tzinfo_to_sql
</strong>
</span>
</a>
program loads the
time zone tables in the
<code class="literal">
mysql
</code>
database. It is
used on systems that have a
<span class="firstterm">
zoneinfo
</span>
database (the set
of files describing time zones). Examples of such systems are
Linux, FreeBSD, Solaris, and macOS. One likely location for
these files is the
<code class="filename">
/usr/share/zoneinfo
</code>
directory (
<code class="filename">
/usr/share/lib/zoneinfo
</code>
on
Solaris). If your system does not have a zoneinfo database, you
can use the downloadable package described in
<a class="xref" href="time-zone-support.html" title="7.1.15 MySQL Server Time Zone Support">
Section 7.1.15, “MySQL Server Time Zone Support”
</a>
.
</p>
<p>
<a class="link" href="mysql-tzinfo-to-sql.html" title="6.4.3 mysql_tzinfo_to_sql — Load the Time Zone Tables">
<span class="command">
<strong>
mysql_tzinfo_to_sql
</strong>
</span>
</a>
can be invoked several
ways:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-terminal"><div class="docs-select-all right" id="sa32541407"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal">mysql_tzinfo_to_sql <em class="replaceable">tz_dir</em>
mysql_tzinfo_to_sql <em class="replaceable">tz_file tz_name</em>
mysql_tzinfo_to_sql <span class="token property">--leap</span> <em class="replaceable">tz_file</em></code></pre>
</div>
<p>
For the first invocation syntax, pass the zoneinfo directory
path name to
<a class="link" href="mysql-tzinfo-to-sql.html" title="6.4.3 mysql_tzinfo_to_sql — Load the Time Zone Tables">
<span class="command">
<strong>
mysql_tzinfo_to_sql
</strong>
</span>
</a>
and send the
output into the
<a class="link" href="mysql.html" title="6.5.1 mysql — The MySQL Command-Line Client">
<span class="command">
<strong>
mysql
</strong>
</span>
</a>
program. For example:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-terminal"><div class="docs-select-all right" id="sa41397936"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal">mysql_tzinfo_to_sql /usr/share/zoneinfo | mysql <span class="token property">-u</span> root mysql</code></pre>
</div>
<p>
<a class="link" href="mysql-tzinfo-to-sql.html" title="6.4.3 mysql_tzinfo_to_sql — Load the Time Zone Tables">
<span class="command">
<strong>
mysql_tzinfo_to_sql
</strong>
</span>
</a>
reads your system's time
zone files and generates SQL statements from them.
<a class="link" href="mysql.html" title="6.5.1 mysql — The MySQL Command-Line Client">
<span class="command">
<strong>
mysql
</strong>
</span>
</a>
processes those statements to load the
time zone tables.
</p>
<p>
The second syntax causes
<a class="link" href="mysql-tzinfo-to-sql.html" title="6.4.3 mysql_tzinfo_to_sql — Load the Time Zone Tables">
<span class="command">
<strong>
mysql_tzinfo_to_sql
</strong>
</span>
</a>
to load a single time zone file
<em class="replaceable">
<code>
tz_file
</code>
</em>
that corresponds to a time
zone name
<em class="replaceable">
<code>
tz_name
</code>
</em>
:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-terminal"><div class="docs-select-all right" id="sa32285612"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal">mysql_tzinfo_to_sql <em class="replaceable">tz_file</em> <em class="replaceable">tz_name</em> | mysql <span class="token property">-u</span> root mysql</code></pre>
</div>
<p>
If your time zone needs to account for leap seconds, invoke
<a class="link" href="mysql-tzinfo-to-sql.html" title="6.4.3 mysql_tzinfo_to_sql — Load the Time Zone Tables">
<span class="command">
<strong>
mysql_tzinfo_to_sql
</strong>
</span>
</a>
using the third syntax,
which initializes the leap second information.
<em class="replaceable">
<code>
tz_file
</code>
</em>
is the name of your time zone
file:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-terminal"><div class="docs-select-all right" id="sa90522193"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal">mysql_tzinfo_to_sql <span class="token property">--leap</span> <em class="replaceable">tz_file</em> | mysql <span class="token property">-u</span> root mysql</code></pre>
</div>
<p>
After running
<a class="link" href="mysql-tzinfo-to-sql.html" title="6.4.3 mysql_tzinfo_to_sql — Load the Time Zone Tables">
<span class="command">
<strong>
mysql_tzinfo_to_sql
</strong>
</span>
</a>
, it is best
to restart the server so that it does not continue to use any
previously cached time zone data.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/show-plugins.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="show-plugins">
</a>
15.7.7.27 SHOW PLUGINS Statement
</h4>
</div>
</div>
</div>
<a class="indexterm" name="idm46045170049440">
</a>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-sql"><div class="docs-select-all right" id="sa84612832"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">SHOW</span> <span class="token keyword">PLUGINS</span></code></pre>
</div>
<p>
<a class="link" href="show-plugins.html" title="15.7.7.27 SHOW PLUGINS Statement">
<code class="literal">
SHOW PLUGINS
</code>
</a>
displays information
about server plugins.
</p>
<p>
Example of
<a class="link" href="show-plugins.html" title="15.7.7.27 SHOW PLUGINS Statement">
<code class="literal">
SHOW PLUGINS
</code>
</a>
output:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa86623959"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SHOW</span> <span class="token keyword">PLUGINS</span>\G
<span class="token output"><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span> 1. row <span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span>
Name<span class="token punctuation">:</span> binlog
Status<span class="token punctuation">:</span> ACTIVE
Type<span class="token punctuation">:</span> STORAGE ENGINE
Library<span class="token punctuation">:</span> NULL
License<span class="token punctuation">:</span> GPL
<span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span> 2. row <span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span>
Name<span class="token punctuation">:</span> CSV
Status<span class="token punctuation">:</span> ACTIVE
Type<span class="token punctuation">:</span> STORAGE ENGINE
Library<span class="token punctuation">:</span> NULL
License<span class="token punctuation">:</span> GPL
<span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span> 3. row <span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span>
Name<span class="token punctuation">:</span> MEMORY
Status<span class="token punctuation">:</span> ACTIVE
Type<span class="token punctuation">:</span> STORAGE ENGINE
Library<span class="token punctuation">:</span> NULL
License<span class="token punctuation">:</span> GPL
<span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span> 4. row <span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span>
Name<span class="token punctuation">:</span> MyISAM
Status<span class="token punctuation">:</span> ACTIVE
Type<span class="token punctuation">:</span> STORAGE ENGINE
Library<span class="token punctuation">:</span> NULL
License<span class="token punctuation">:</span> GPL
...</span></code></pre>
</div>
<p>
<a class="link" href="show-plugins.html" title="15.7.7.27 SHOW PLUGINS Statement">
<code class="literal">
SHOW PLUGINS
</code>
</a>
output has these
columns:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<code class="literal">
Name
</code>
</p>
<p>
The name used to refer to the plugin in statements such as
<a class="link" href="install-plugin.html" title="15.7.4.4 INSTALL PLUGIN Statement">
<code class="literal">
INSTALL PLUGIN
</code>
</a>
and
<a class="link" href="uninstall-plugin.html" title="15.7.4.6 UNINSTALL PLUGIN Statement">
<code class="literal">
UNINSTALL PLUGIN
</code>
</a>
.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Status
</code>
</p>
<p>
The plugin status, one of
<code class="literal">
ACTIVE
</code>
,
<code class="literal">
INACTIVE
</code>
,
<code class="literal">
DISABLED
</code>
,
<code class="literal">
DELETING
</code>
, or
<code class="literal">
DELETED
</code>
.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Type
</code>
</p>
<p>
The type of plugin, such as
<code class="literal">
STORAGE
ENGINE
</code>
,
<code class="literal">
INFORMATION_SCHEMA
</code>
, or
<code class="literal">
AUTHENTICATION
</code>
.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Library
</code>
</p>
<p>
The name of the plugin shared library file. This is the name
used to refer to the plugin file in statements such as
<a class="link" href="install-plugin.html" title="15.7.4.4 INSTALL PLUGIN Statement">
<code class="literal">
INSTALL PLUGIN
</code>
</a>
and
<a class="link" href="uninstall-plugin.html" title="15.7.4.6 UNINSTALL PLUGIN Statement">
<code class="literal">
UNINSTALL PLUGIN
</code>
</a>
. This file
is located in the directory named by the
<a class="link" href="server-system-variables.html#sysvar_plugin_dir">
<code class="literal">
plugin_dir
</code>
</a>
system variable.
If the library name is
<code class="literal">
NULL
</code>
, the plugin
is compiled in and cannot be uninstalled with
<a class="link" href="uninstall-plugin.html" title="15.7.4.6 UNINSTALL PLUGIN Statement">
<code class="literal">
UNINSTALL PLUGIN
</code>
</a>
.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
License
</code>
</p>
<p>
How the plugin is licensed (for example,
<code class="literal">
GPL
</code>
).
</p>
</li>
</ul>
</div>
<p>
For plugins installed with
<a class="link" href="install-plugin.html" title="15.7.4.4 INSTALL PLUGIN Statement">
<code class="literal">
INSTALL
PLUGIN
</code>
</a>
, the
<code class="literal">
Name
</code>
and
<code class="literal">
Library
</code>
values are also registered in the
<code class="literal">
mysql.plugin
</code>
system table.
</p>
<p>
For information about plugin data structures that form the basis
of the information displayed by
<a class="link" href="show-plugins.html" title="15.7.7.27 SHOW PLUGINS Statement">
<code class="literal">
SHOW
PLUGINS
</code>
</a>
, see
<a class="ulink" href="/doc/extending-mysql/8.4/en/plugin-api.html" target="_top">
The MySQL Plugin API
</a>
.
</p>
<p>
Plugin information is also available from the
<code class="literal">
INFORMATION_SCHEMA
</code>
<code class="literal">
.PLUGINS
</code>
table. See
<a class="xref" href="information-schema-plugins-table.html" title="28.3.22 The INFORMATION_SCHEMA PLUGINS Table">
Section 28.3.22, “The INFORMATION_SCHEMA PLUGINS Table”
</a>
.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-ndbinfo-cpustat-50ms.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="mysql-cluster-ndbinfo-cpustat-50ms">
</a>
25.6.17.20 The ndbinfo cpustat_50ms Table
</h4>
</div>
</div>
</div>
<a class="indexterm" name="idm46045089912736">
</a>
<p>
The
<code class="literal">
cpustat_50ms
</code>
table provides raw,
per-thread CPU data obtained each 50 milliseconds for each
thread running in the
<code class="literal">
NDB
</code>
kernel.
</p>
<p>
Like
<a class="link" href="mysql-cluster-ndbinfo-cpustat-1sec.html" title="25.6.17.21 The ndbinfo cpustat_1sec Table">
<code class="literal">
cpustat_1sec
</code>
</a>
and
<a class="link" href="mysql-cluster-ndbinfo-cpustat-20sec.html" title="25.6.17.22 The ndbinfo cpustat_20sec Table">
<code class="literal">
cpustat_20sec
</code>
</a>
, this table
shows 20 measurement sets per thread, each referencing a period
of the named duration. Thus,
<code class="literal">
cpsustat_50ms
</code>
provides 1 second of history.
</p>
<p>
The
<code class="literal">
cpustat_50ms
</code>
table contains the following
columns:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<code class="literal">
node_id
</code>
</p>
<p>
ID of the node where the thread is running
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
thr_no
</code>
</p>
<p>
Thread ID (specific to this node)
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
OS_user_time
</code>
</p>
<p>
OS user time
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
OS_system_time
</code>
</p>
<p>
OS system time
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
OS_idle_time
</code>
</p>
<p>
OS idle time
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
exec_time
</code>
</p>
<p>
Thread execution time
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
sleep_time
</code>
</p>
<p>
Thread sleep time
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
spin_time
</code>
</p>
<p>
Thread spin time
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
send_time
</code>
</p>
<p>
Thread send time
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
buffer_full_time
</code>
</p>
<p>
Thread buffer full time
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
elapsed_time
</code>
</p>
<p>
Elapsed time
</p>
</li>
</ul>
</div>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-log-startup-messages.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="mysql-cluster-log-startup-messages">
</a>
25.6.2.2 NDB Cluster Log Startup Messages
</h4>
</div>
</div>
</div>
<p>
Possible startup messages with descriptions are provided in the
following list:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<code class="literal">
Initial start, waiting for %s to connect, nodes [
all: %s connected: %s no-wait: %s ]
</code>
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Waiting until nodes: %s connects, nodes [ all: %s
connected: %s no-wait: %s ]
</code>
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Waiting %u sec for nodes %s to connect, nodes [
all: %s connected: %s no-wait: %s ]
</code>
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Waiting for non partitioned start, nodes [ all: %s
connected: %s missing: %s no-wait: %s ]
</code>
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Waiting %u sec for non partitioned start, nodes [
all: %s connected: %s missing: %s no-wait: %s ]
</code>
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Initial start with nodes %s [ missing: %s no-wait:
%s ]
</code>
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Start with all nodes %s
</code>
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Start with nodes %s [ missing: %s no-wait: %s
]
</code>
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Start potentially partitioned with nodes %s [
missing: %s no-wait: %s ]
</code>
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Unknown startreport: 0x%x [ %s %s %s %s ]
</code>
</p>
</li>
</ul>
</div>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/keyring-encrypted-file-component.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="keyring-encrypted-file-component">
</a>
8.4.4.5 Using the component_keyring_encrypted_file Encrypted File-Based Keyring
Component
</h4>
</div>
</div>
</div>
<a class="indexterm" name="idm46045240751328">
</a>
<a class="indexterm" name="idm46045240750224">
</a>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Note
</div>
<p>
<code class="literal">
component_keyring_encrypted_file
</code>
is an
extension included in MySQL Enterprise Edition, a commercial product. To learn
more about commercial products, see
<a class="ulink" href="https://www.mysql.com/products/" target="_blank">
https://www.mysql.com/products/
</a>
.
</p>
</div>
<p>
The
<code class="literal">
component_keyring_encrypted_file
</code>
keyring
component stores keyring data in an encrypted,
password-protected file local to the server host.
</p>
<div class="warning" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Warning
</div>
<p>
For encryption key management, the
<code class="literal">
component_keyring_file
</code>
and
<code class="literal">
component_keyring_encrypted_file
</code>
components
are not intended as a regulatory compliance solution. Security
standards such as PCI, FIPS, and others require use of key
management systems to secure, manage, and protect encryption
keys in key vaults or hardware security modules (HSMs).
</p>
</div>
<p>
To use
<code class="literal">
component_keyring_encrypted_file
</code>
for
keystore management, you must:
</p>
<div class="orderedlist">
<ol class="orderedlist" type="1">
<li class="listitem">
<p>
Write a manifest that tells the server to load
<code class="literal">
component_keyring_encrypted_file
</code>
, as
described in
<a class="xref" href="keyring-component-installation.html" title="8.4.4.2 Keyring Component Installation">
Section 8.4.4.2, “Keyring Component Installation”
</a>
.
</p>
</li>
<li class="listitem">
<p>
Write a configuration file for
<code class="literal">
component_keyring_encrypted_file
</code>
, as
described here.
</p>
</li>
</ol>
</div>
<p>
When it initializes,
<code class="literal">
component_keyring_encrypted_file
</code>
reads either
a global configuration file, or a global configuration file
paired with a local configuration file:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
The component attempts to read its global configuration file
from the directory where the component library file is
installed (that is, the server plugin directory).
</p>
</li>
<li class="listitem">
<p>
If the global configuration file indicates use of a local
configuration file, the component attempts to read its local
configuration file from the data directory.
</p>
</li>
<li class="listitem">
<p>
Although global and local configuration files are located in
different directories, the file name is
<code class="filename">
component_keyring_encrypted_file.cnf
</code>
in
both locations.
</p>
</li>
<li class="listitem">
<p>
If
<code class="literal">
component_keyring_encrypted_file
</code>
cannot find the configuration file, an error results, and
the component cannot initialize.
</p>
</li>
</ul>
</div>
<p>
Local configuration files permit setting up multiple server
instances to use
<code class="literal">
component_keyring_encrypted_file
</code>
, such that
component configuration for each server instance is specific to
a given data directory instance. This enables the same keyring
component to be used with a distinct data file for each
instance.
</p>
<p>
<code class="literal">
component_keyring_encrypted_file
</code>
configuration files have these properties:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
A configuration file must be in valid JSON format.
</p>
</li>
<li class="listitem">
<p>
A configuration file permits these configuration items:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
<code class="literal">
"read_local_config"
</code>
: This item is
permitted only in the global configuration file. If the
item is not present, the component uses only the global
configuration file. If the item is present, its value is
<code class="literal">
true
</code>
or
<code class="literal">
false
</code>
,
indicating whether the component should read
configuration information from the local configuration
file.
</p>
<p>
If the
<code class="literal">
"read_local_config"
</code>
item is
present in the global configuration file along with
other items, the component checks the
<code class="literal">
"read_local_config"
</code>
item value first:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: square; ">
<li class="listitem">
<p>
If the value is
<code class="literal">
false
</code>
, the
component processes the other items in the global
configuration file and ignores the local
configuration file.
</p>
</li>
<li class="listitem">
<p>
If the value is
<code class="literal">
true
</code>
, the
component ignores the other items in the global
configuration file and attempts to read the local
configuration file.
</p>
</li>
</ul>
</div>
</li>
<li class="listitem">
<p>
<code class="literal">
"path"
</code>
: The item value is a string
that names the file to use for storing keyring data. The
file should be named using an absolute path, not a
relative path. This item is mandatory in the
configuration. If not specified,
<code class="literal">
component_keyring_encrypted_file
</code>
initialization fails.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
"password"
</code>
: The item value is a
string that specifies the password for accessing the
data file. This item is mandatory in the configuration.
If not specified,
<code class="literal">
component_keyring_encrypted_file
</code>
initialization fails.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
"read_only"
</code>
: The item value indicates
whether the keyring data file is read only. The item
value is
<code class="literal">
true
</code>
(read only) or
<code class="literal">
false
</code>
(read/write). This item is
mandatory in the configuration. If not specified,
<code class="literal">
component_keyring_encrypted_file
</code>
initialization fails.
</p>
</li>
</ul>
</div>
</li>
<li class="listitem">
<p>
The database administrator has the responsibility for
creating any configuration files to be used, and for
ensuring that their contents are correct. If an error
occurs, server startup fails and the administrator must
correct any issues indicated by diagnostics in the server
error log.
</p>
</li>
<li class="listitem">
<p>
Any configuration file that stores a password should have a
restrictive mode and be accessible only to the account used
to run the MySQL server.
</p>
</li>
</ul>
</div>
<p>
Given the preceding configuration file properties, to configure
<code class="literal">
component_keyring_encrypted_file
</code>
, create a
global configuration file named
<code class="filename">
component_keyring_encrypted_file.cnf
</code>
in the
directory where the
<code class="literal">
component_keyring_encrypted_file
</code>
library file
is installed, and optionally create a local configuration file,
also named
<code class="filename">
component_keyring_encrypted_file.cnf
</code>
, in
the data directory. The following instructions assume that a
keyring data file named
<code class="filename">
/usr/local/mysql/keyring/component_keyring_encrypted_file
</code>
is to be used in read/write fashion. You must also choose a
password.
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
To use a global configuration file only, the file contents
look like this:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-json"><div class="docs-select-all right" id="sa88386220"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-json"><span class="token punctuation">{</span>
<span class="token property">"path"</span><span class="token operator">:</span> <span class="token string">"/usr/local/mysql/keyring/component_keyring_encrypted_file"</span><span class="token punctuation">,</span>
<span class="token property">"password"</span><span class="token operator">:</span> <span class="token string">"<em class="replaceable">password</em>"</span><span class="token punctuation">,</span>
<span class="token property">"read_only"</span><span class="token operator">:</span> <span class="token boolean">false</span>
<span class="token punctuation">}</span></code></pre>
</div>
<p>
Create this file in the directory where the
<code class="literal">
component_keyring_encrypted_file
</code>
library
file is installed.
</p>
<p>
This path must not point to or include the MySQL data
directory.
</p>
</li>
<li class="listitem">
<p>
Alternatively, to use a global and local configuration file
pair, the global file looks like this:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-json"><div class="docs-select-all right" id="sa75021922"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-json"><span class="token punctuation">{</span>
<span class="token property">"read_local_config"</span><span class="token operator">:</span> <span class="token boolean">true</span>
<span class="token punctuation">}</span></code></pre>
</div>
<p>
Create this file in the directory where the
<code class="literal">
component_keyring_encrypted_file
</code>
library
file is installed.
</p>
<p>
The local file looks like this:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-json"><div class="docs-select-all right" id="sa37575833"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-json"><span class="token punctuation">{</span>
<span class="token property">"path"</span><span class="token operator">:</span> <span class="token string">"/usr/local/mysql/keyring/component_keyring_encrypted_file"</span><span class="token punctuation">,</span>
<span class="token property">"password"</span><span class="token operator">:</span> <span class="token string">"<em class="replaceable">password</em>"</span><span class="token punctuation">,</span>
<span class="token property">"read_only"</span><span class="token operator">:</span> <span class="token boolean">false</span>
<span class="token punctuation">}</span></code></pre>
</div>
<p>
This path must not point to or include the MySQL data
directory.
</p>
</li>
</ul>
</div>
<p>
Keyring operations are transactional:
<code class="literal">
component_keyring_encrypted_file
</code>
uses a
backup file during write operations to ensure that it can roll
back to the original file if an operation fails. The backup file
has the same name as the data file with a suffix of
<code class="filename">
.backup
</code>
.
</p>
<p>
<code class="literal">
component_keyring_encrypted_file
</code>
supports the
functions that comprise the standard MySQL Keyring service
interface. Keyring operations performed by those functions are
accessible in SQL statements as described in
<a class="xref" href="keyring-functions-general-purpose.html" title="8.4.4.12 General-Purpose Keyring Key-Management Functions">
Section 8.4.4.12, “General-Purpose Keyring Key-Management Functions”
</a>
.
</p>
<p>
Example:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa23240467"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">SELECT</span> keyring_key_generate<span class="token punctuation">(</span><span class="token string">'MyKey'</span><span class="token punctuation">,</span> <span class="token string">'AES'</span><span class="token punctuation">,</span> <span class="token number">32</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token keyword">SELECT</span> keyring_key_remove<span class="token punctuation">(</span><span class="token string">'MyKey'</span><span class="token punctuation">)</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
For information about the characteristics of key values
permitted by
<code class="literal">
component_keyring_encrypted_file
</code>
, see
<a class="xref" href="keyring-key-types.html" title="8.4.4.10 Supported Keyring Key Types and Lengths">
Section 8.4.4.10, “Supported Keyring Key Types and Lengths”
</a>
.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/information-schema-schemata-extensions-table.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="information-schema-schemata-extensions-table">
</a>
28.3.32 The INFORMATION_SCHEMA SCHEMATA_EXTENSIONS Table
</h3>
</div>
</div>
</div>
<a class="indexterm" name="idm46045078741488">
</a>
<p>
The
<a class="link" href="information-schema-schemata-extensions-table.html" title="28.3.32 The INFORMATION_SCHEMA SCHEMATA_EXTENSIONS Table">
<code class="literal">
SCHEMATA_EXTENSIONS
</code>
</a>
table
augments the
<a class="link" href="information-schema-schemata-table.html" title="28.3.31 The INFORMATION_SCHEMA SCHEMATA Table">
<code class="literal">
SCHEMATA
</code>
</a>
table with
information about schema options.
</p>
<p>
The
<a class="link" href="information-schema-schemata-extensions-table.html" title="28.3.32 The INFORMATION_SCHEMA SCHEMATA_EXTENSIONS Table">
<code class="literal">
SCHEMATA_EXTENSIONS
</code>
</a>
table has
these columns:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<code class="literal">
CATALOG_NAME
</code>
</p>
<p>
The name of the catalog to which the schema belongs. This
value is always
<code class="literal">
def
</code>
.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
SCHEMA_NAME
</code>
</p>
<p>
The name of the schema.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
OPTIONS
</code>
</p>
<p>
The options for the schema. If the schema is read only, the
value contains
<code class="literal">
READ ONLY=1
</code>
. If the schema
is not read only, no
<code class="literal">
READ ONLY
</code>
option
appears.
</p>
</li>
</ul>
</div>
<h4>
<a name="idm46045078726896">
</a>
Example
</h4>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa64300206"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">ALTER</span> <span class="token keyword">SCHEMA</span> mydb <span class="token keyword">READ</span> <span class="token keyword">ONLY</span> <span class="token operator">=</span> <span class="token number">1</span><span class="token punctuation">;</span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token operator">*</span> <span class="token keyword">FROM</span> INFORMATION_SCHEMA<span class="token punctuation">.</span>SCHEMATA_EXTENSIONS
<span class="token keyword">WHERE</span> <span class="token keyword">SCHEMA_NAME</span> <span class="token operator">=</span> <span class="token string">'mydb'</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> CATALOG_NAME <span class="token punctuation">|</span> SCHEMA_NAME <span class="token punctuation">|</span> OPTIONS <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> def <span class="token punctuation">|</span> mydb <span class="token punctuation">|</span> READ ONLY=1 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token prompt">mysql></span> <span class="token keyword">ALTER</span> <span class="token keyword">SCHEMA</span> mydb <span class="token keyword">READ</span> <span class="token keyword">ONLY</span> <span class="token operator">=</span> <span class="token number">0</span><span class="token punctuation">;</span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token operator">*</span> <span class="token keyword">FROM</span> INFORMATION_SCHEMA<span class="token punctuation">.</span>SCHEMATA_EXTENSIONS
<span class="token keyword">WHERE</span> <span class="token keyword">SCHEMA_NAME</span> <span class="token operator">=</span> <span class="token string">'mydb'</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> CATALOG_NAME <span class="token punctuation">|</span> SCHEMA_NAME <span class="token punctuation">|</span> OPTIONS <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> def <span class="token punctuation">|</span> mydb <span class="token punctuation">|</span> <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span></code></pre>
</div>
<h4>
<a name="idm46045078720256">
</a>
Notes
</h4>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<a class="link" href="information-schema-schemata-extensions-table.html" title="28.3.32 The INFORMATION_SCHEMA SCHEMATA_EXTENSIONS Table">
<code class="literal">
SCHEMATA_EXTENSIONS
</code>
</a>
is a
nonstandard
<code class="literal">
INFORMATION_SCHEMA
</code>
table.
</p>
</li>
</ul>
</div>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/ansi-diff-foreign-keys.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="ansi-diff-foreign-keys">
</a>
1.7.2.3 FOREIGN KEY Constraint Differences
</h4>
</div>
</div>
</div>
<a class="indexterm" name="idm46045333254784">
</a>
<a class="indexterm" name="idm46045333253744">
</a>
<p>
The MySQL implementation of foreign key constraints differs
from the SQL standard in the following key respects:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
If there are several rows in the parent table with the
same referenced key value,
<a class="link" href="innodb-storage-engine.html" title="Chapter 17 The InnoDB Storage Engine">
<code class="literal">
InnoDB
</code>
</a>
performs a foreign key
check as if the other parent rows with the same key value
do not exist. For example, if you define a
<code class="literal">
RESTRICT
</code>
type constraint, and there is
a child row with several parent rows,
<code class="literal">
InnoDB
</code>
does not permit the deletion of
any of the parent rows. This is shown in the following
example:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa40707673"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">CREATE</span> <span class="token keyword">TABLE</span> parent <span class="token punctuation">(</span>
<span class="token prompt"> -></span> id <span class="token datatype">INT</span><span class="token punctuation">,</span>
<span class="token prompt"> -></span> <span class="token keyword">INDEX</span> <span class="token punctuation">(</span>id<span class="token punctuation">)</span>
<span class="token prompt"> -></span> <span class="token punctuation">)</span> <span class="token keyword">ENGINE</span><span class="token operator">=</span>InnoDB<span class="token punctuation">;</span>
<span class="token output">Query OK, 0 rows affected (0.04 sec)</span>
<span class="token prompt">mysql></span> <span class="token keyword">CREATE</span> <span class="token keyword">TABLE</span> child <span class="token punctuation">(</span>
<span class="token prompt"> -></span> id <span class="token datatype">INT</span><span class="token punctuation">,</span>
<span class="token prompt"> -></span> parent_id <span class="token datatype">INT</span><span class="token punctuation">,</span>
<span class="token prompt"> -></span> <span class="token keyword">INDEX</span> par_ind <span class="token punctuation">(</span>parent_id<span class="token punctuation">)</span><span class="token punctuation">,</span>
<span class="token prompt"> -></span> <span class="token keyword">FOREIGN</span> <span class="token keyword">KEY</span> <span class="token punctuation">(</span>parent_id<span class="token punctuation">)</span>
<span class="token prompt"> -></span> <span class="token keyword">REFERENCES</span> parent<span class="token punctuation">(</span>id<span class="token punctuation">)</span>
<span class="token prompt"> -></span> <span class="token keyword">ON</span> <span class="token keyword">DELETE</span> <span class="token keyword">RESTRICT</span>
<span class="token prompt"> -></span> <span class="token punctuation">)</span> <span class="token keyword">ENGINE</span><span class="token operator">=</span>InnoDB<span class="token punctuation">;</span>
<span class="token output">Query OK, 0 rows affected (0.02 sec)</span>
<span class="token prompt">mysql></span> <span class="token keyword">INSERT</span> <span class="token keyword">INTO</span> parent <span class="token punctuation">(</span>id<span class="token punctuation">)</span>
<span class="token prompt"> -></span> <span class="token keyword">VALUES</span> <span class="token keyword">ROW</span><span class="token punctuation">(</span><span class="token number">1</span><span class="token punctuation">)</span><span class="token punctuation">,</span> <span class="token keyword">ROW</span><span class="token punctuation">(</span><span class="token number">2</span><span class="token punctuation">)</span><span class="token punctuation">,</span> <span class="token keyword">ROW</span><span class="token punctuation">(</span><span class="token number">3</span><span class="token punctuation">)</span><span class="token punctuation">,</span> <span class="token keyword">ROW</span><span class="token punctuation">(</span><span class="token number">1</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output">Query OK, 4 rows affected (0.01 sec)</span>
<span class="token output">Records: 4 Duplicates: 0 Warnings: 0</span>
<span class="token prompt">mysql></span> <span class="token keyword">INSERT</span> <span class="token keyword">INTO</span> child <span class="token punctuation">(</span>id<span class="token punctuation">,</span>parent_id<span class="token punctuation">)</span>
<span class="token prompt"> -></span> <span class="token keyword">VALUES</span> <span class="token keyword">ROW</span><span class="token punctuation">(</span><span class="token number">1</span><span class="token punctuation">,</span><span class="token number">1</span><span class="token punctuation">)</span><span class="token punctuation">,</span> <span class="token keyword">ROW</span><span class="token punctuation">(</span><span class="token number">2</span><span class="token punctuation">,</span><span class="token number">2</span><span class="token punctuation">)</span><span class="token punctuation">,</span> <span class="token keyword">ROW</span><span class="token punctuation">(</span><span class="token number">3</span><span class="token punctuation">,</span><span class="token number">3</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output">Query OK, 3 rows affected (0.01 sec)</span>
<span class="token output">Records: 3 Duplicates: 0 Warnings: 0</span>
<span class="token prompt">mysql></span> <span class="token keyword">DELETE</span> <span class="token keyword">FROM</span> parent <span class="token keyword">WHERE</span> id<span class="token operator">=</span><span class="token number">1</span><span class="token punctuation">;</span>
<span class="token output">ERROR 1451 (23000)<span class="token punctuation">:</span> Cannot delete or update a parent row<span class="token punctuation">:</span> a foreign key
constraint fails (`test`.`child`, CONSTRAINT `child_ibfk_1` FOREIGN KEY
(`parent_id`) REFERENCES `parent` (`id`) ON DELETE RESTRICT)</span></code></pre>
</div>
</li>
<li class="listitem">
<p>
If
<code class="literal">
ON UPDATE CASCADE
</code>
or
<code class="literal">
ON
UPDATE SET NULL
</code>
recurses to update the
<span class="emphasis">
<em>
same table
</em>
</span>
it has previously updated
during the same cascade, it acts like
<code class="literal">
RESTRICT
</code>
. This means that you cannot
use self-referential
<code class="literal">
ON UPDATE CASCADE
</code>
or
<code class="literal">
ON UPDATE SET NULL
</code>
operations. This
is to prevent infinite loops resulting from cascaded
updates. A self-referential
<code class="literal">
ON DELETE SET
NULL
</code>
, on the other hand, is possible, as is a
self-referential
<code class="literal">
ON DELETE CASCADE
</code>
.
Cascading operations may not be nested more than 15 levels
deep.
</p>
</li>
<li class="listitem">
<p>
In an SQL statement that inserts, deletes, or updates many
rows, foreign key constraints (like unique constraints)
are checked row-by-row. When performing foreign key
checks,
<a class="link" href="innodb-storage-engine.html" title="Chapter 17 The InnoDB Storage Engine">
<code class="literal">
InnoDB
</code>
</a>
sets shared
row-level locks on child or parent records that it must
examine. MySQL checks foreign key constraints immediately;
the check is not deferred to transaction commit. According
to the SQL standard, the default behavior should be
deferred checking. That is, constraints are only checked
after the
<span class="emphasis">
<em>
entire SQL statement
</em>
</span>
has
been processed. This means that it is not possible to
delete a row that refers to itself using a foreign key.
</p>
</li>
<li class="listitem">
<p>
No storage engine, including
<code class="literal">
InnoDB
</code>
,
recognizes or enforces the
<code class="literal">
MATCH
</code>
clause
used in referential-integrity constraint definitions. Use
of an explicit
<code class="literal">
MATCH
</code>
clause does not
have the specified effect, and it causes
<code class="literal">
ON
DELETE
</code>
and
<code class="literal">
ON UPDATE
</code>
clauses
to be ignored. Specifying the
<code class="literal">
MATCH
</code>
should be avoided.
</p>
<p>
The
<code class="literal">
MATCH
</code>
clause in the SQL standard
controls how
<code class="literal">
NULL
</code>
values in a composite
(multiple-column) foreign key are handled when comparing
to a primary key in the referenced table. MySQL
essentially implements the semantics defined by
<code class="literal">
MATCH SIMPLE
</code>
, which permits a foreign
key to be all or partially
<code class="literal">
NULL
</code>
. In
that case, a (child table) row containing such a foreign
key can be inserted even though it does not match any row
in the referenced (parent) table. (It is possible to
implement other semantics using triggers.)
</p>
</li>
<li class="listitem">
<p>
A
<code class="literal">
FOREIGN KEY
</code>
constraint that
references a non-
<code class="literal">
UNIQUE
</code>
key is not
standard SQL but rather an
<a class="link" href="innodb-storage-engine.html" title="Chapter 17 The InnoDB Storage Engine">
<code class="literal">
InnoDB
</code>
</a>
extension that is now
deprecated, and must be enabled by setting
<a class="link" href="server-system-variables.html#sysvar_restrict_fk_on_non_standard_key">
<code class="literal">
restrict_fk_on_non_standard_key
</code>
</a>
.
You should expect support for use of nonstandard keys to
be removed in a future version of MySQL, and migrate away
from them now.
</p>
<p>
The
<a class="link" href="mysql-cluster.html" title="Chapter 25 MySQL NDB Cluster 8.4">
<code class="literal">
NDB
</code>
</a>
storage engine
requires an explicit unique key (or primary key) on any
column referenced as a foreign key, as per the SQL
standard.
</p>
</li>
<li class="listitem">
<p>
For storage engines that do not support foreign keys (such
as
<a class="link" href="myisam-storage-engine.html" title="18.2 The MyISAM Storage Engine">
<code class="literal">
MyISAM
</code>
</a>
), MySQL Server
parses and ignores foreign key specifications.
</p>
</li>
<li class="listitem">
<p>
MySQL parses but ignores
<span class="quote">
“
<span class="quote">
inline
<code class="literal">
REFERENCES
</code>
specifications
</span>
”
</span>
(as
defined in the SQL standard) where the references are
defined as part of the column specification. MySQL accepts
<code class="literal">
REFERENCES
</code>
clauses only when specified
as part of a separate
<code class="literal">
FOREIGN KEY
</code>
specification.
</p>
<p>
Defining a column to use a
<code class="literal">
REFERENCES
<em class="replaceable">
<code>
tbl_name
</code>
</em>
(
<em class="replaceable">
<code>
col_name
</code>
</em>
)
</code>
clause has no actual effect and
<span class="emphasis">
<em>
serves only as a
memo or comment to you that the column which you are
currently defining is intended to refer to a column in
another table
</em>
</span>
. It is important to realize when
using this syntax that:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
MySQL does not perform any sort of check to make sure
that
<em class="replaceable">
<code>
col_name
</code>
</em>
actually
exists in
<em class="replaceable">
<code>
tbl_name
</code>
</em>
(or even
that
<em class="replaceable">
<code>
tbl_name
</code>
</em>
itself
exists).
</p>
</li>
<li class="listitem">
<p>
MySQL does not perform any sort of action on
<em class="replaceable">
<code>
tbl_name
</code>
</em>
such as deleting
rows in response to actions taken on rows in the table
which you are defining; in other words, this syntax
induces no
<code class="literal">
ON DELETE
</code>
or
<code class="literal">
ON
UPDATE
</code>
behavior whatsoever. (Although you
can write an
<code class="literal">
ON DELETE
</code>
or
<code class="literal">
ON UPDATE
</code>
clause as part of the
<code class="literal">
REFERENCES
</code>
clause, it is also
ignored.)
</p>
</li>
<li class="listitem">
<p>
This syntax creates a
<span class="emphasis">
<em>
column
</em>
</span>
; it
does
<span class="bold">
<strong>
not
</strong>
</span>
create any
sort of index or key.
</p>
</li>
</ul>
</div>
<p>
You can use a column so created as a join column, as shown
here:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa99434239"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">CREATE</span> <span class="token keyword">TABLE</span> person <span class="token punctuation">(</span>
id <span class="token datatype">SMALLINT</span> <span class="token keyword">UNSIGNED</span> <span class="token operator">NOT</span> <span class="token boolean">NULL</span> <span class="token keyword">AUTO_INCREMENT</span><span class="token punctuation">,</span>
<span class="token keyword">name</span> <span class="token datatype">CHAR</span><span class="token punctuation">(</span><span class="token number">60</span><span class="token punctuation">)</span> <span class="token operator">NOT</span> <span class="token boolean">NULL</span><span class="token punctuation">,</span>
<span class="token keyword">PRIMARY</span> <span class="token keyword">KEY</span> <span class="token punctuation">(</span>id<span class="token punctuation">)</span>
<span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token keyword">CREATE</span> <span class="token keyword">TABLE</span> shirt <span class="token punctuation">(</span>
id <span class="token datatype">SMALLINT</span> <span class="token keyword">UNSIGNED</span> <span class="token operator">NOT</span> <span class="token boolean">NULL</span> <span class="token keyword">AUTO_INCREMENT</span><span class="token punctuation">,</span>
style <span class="token datatype">ENUM</span><span class="token punctuation">(</span><span class="token string">'t-shirt'</span><span class="token punctuation">,</span> <span class="token string">'polo'</span><span class="token punctuation">,</span> <span class="token string">'dress'</span><span class="token punctuation">)</span> <span class="token operator">NOT</span> <span class="token boolean">NULL</span><span class="token punctuation">,</span>
color <span class="token datatype">ENUM</span><span class="token punctuation">(</span><span class="token string">'red'</span><span class="token punctuation">,</span> <span class="token string">'blue'</span><span class="token punctuation">,</span> <span class="token string">'orange'</span><span class="token punctuation">,</span> <span class="token string">'white'</span><span class="token punctuation">,</span> <span class="token string">'black'</span><span class="token punctuation">)</span> <span class="token operator">NOT</span> <span class="token boolean">NULL</span><span class="token punctuation">,</span>
<span class="token keyword">owner</span> <span class="token datatype">SMALLINT</span> <span class="token keyword">UNSIGNED</span> <span class="token operator">NOT</span> <span class="token boolean">NULL</span> <span class="token keyword">REFERENCES</span> person<span class="token punctuation">(</span>id<span class="token punctuation">)</span><span class="token punctuation">,</span>
<span class="token keyword">PRIMARY</span> <span class="token keyword">KEY</span> <span class="token punctuation">(</span>id<span class="token punctuation">)</span>
<span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token keyword">INSERT</span> <span class="token keyword">INTO</span> person <span class="token keyword">VALUES</span> <span class="token punctuation">(</span><span class="token boolean">NULL</span><span class="token punctuation">,</span> <span class="token string">'Antonio Paz'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token keyword">SELECT</span> <span class="token variable">@last</span> <span class="token operator">:=</span> <span class="token function">LAST_INSERT_ID</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token keyword">INSERT</span> <span class="token keyword">INTO</span> shirt <span class="token keyword">VALUES</span>
<span class="token keyword">ROW</span><span class="token punctuation">(</span><span class="token boolean">NULL</span><span class="token punctuation">,</span> <span class="token string">'polo'</span><span class="token punctuation">,</span> <span class="token string">'blue'</span><span class="token punctuation">,</span> <span class="token variable">@last</span><span class="token punctuation">)</span><span class="token punctuation">,</span>
<span class="token keyword">ROW</span><span class="token punctuation">(</span><span class="token boolean">NULL</span><span class="token punctuation">,</span> <span class="token string">'dress'</span><span class="token punctuation">,</span> <span class="token string">'white'</span><span class="token punctuation">,</span> <span class="token variable">@last</span><span class="token punctuation">)</span><span class="token punctuation">,</span>
<span class="token keyword">ROW</span><span class="token punctuation">(</span><span class="token boolean">NULL</span><span class="token punctuation">,</span> <span class="token string">'t-shirt'</span><span class="token punctuation">,</span> <span class="token string">'blue'</span><span class="token punctuation">,</span> <span class="token variable">@last</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token keyword">INSERT</span> <span class="token keyword">INTO</span> person <span class="token keyword">VALUES</span> <span class="token punctuation">(</span><span class="token boolean">NULL</span><span class="token punctuation">,</span> <span class="token string">'Lilliana Angelovska'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token keyword">SELECT</span> <span class="token variable">@last</span> <span class="token operator">:=</span> <span class="token function">LAST_INSERT_ID</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token keyword">INSERT</span> <span class="token keyword">INTO</span> shirt <span class="token keyword">VALUES</span>
<span class="token keyword">ROW</span><span class="token punctuation">(</span><span class="token boolean">NULL</span><span class="token punctuation">,</span> <span class="token string">'dress'</span><span class="token punctuation">,</span> <span class="token string">'orange'</span><span class="token punctuation">,</span> <span class="token variable">@last</span><span class="token punctuation">)</span><span class="token punctuation">,</span>
<span class="token keyword">ROW</span><span class="token punctuation">(</span><span class="token boolean">NULL</span><span class="token punctuation">,</span> <span class="token string">'polo'</span><span class="token punctuation">,</span> <span class="token string">'red'</span><span class="token punctuation">,</span> <span class="token variable">@last</span><span class="token punctuation">)</span><span class="token punctuation">,</span>
<span class="token keyword">ROW</span><span class="token punctuation">(</span><span class="token boolean">NULL</span><span class="token punctuation">,</span> <span class="token string">'dress'</span><span class="token punctuation">,</span> <span class="token string">'blue'</span><span class="token punctuation">,</span> <span class="token variable">@last</span><span class="token punctuation">)</span><span class="token punctuation">,</span>
<span class="token keyword">ROW</span><span class="token punctuation">(</span><span class="token boolean">NULL</span><span class="token punctuation">,</span> <span class="token string">'t-shirt'</span><span class="token punctuation">,</span> <span class="token string">'white'</span><span class="token punctuation">,</span> <span class="token variable">@last</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token keyword">SELECT</span> <span class="token operator">*</span> <span class="token keyword">FROM</span> person<span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> id <span class="token punctuation">|</span> name <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> 1 <span class="token punctuation">|</span> Antonio Paz <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> 2 <span class="token punctuation">|</span> Lilliana Angelovska <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token keyword">SELECT</span> <span class="token operator">*</span> <span class="token keyword">FROM</span> shirt<span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> id <span class="token punctuation">|</span> style <span class="token punctuation">|</span> color <span class="token punctuation">|</span> owner <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> 1 <span class="token punctuation">|</span> polo <span class="token punctuation">|</span> blue <span class="token punctuation">|</span> 1 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> 2 <span class="token punctuation">|</span> dress <span class="token punctuation">|</span> white <span class="token punctuation">|</span> 1 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> 3 <span class="token punctuation">|</span> t<span class="token punctuation">-</span>shirt <span class="token punctuation">|</span> blue <span class="token punctuation">|</span> 1 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> 4 <span class="token punctuation">|</span> dress <span class="token punctuation">|</span> orange <span class="token punctuation">|</span> 2 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> 5 <span class="token punctuation">|</span> polo <span class="token punctuation">|</span> red <span class="token punctuation">|</span> 2 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> 6 <span class="token punctuation">|</span> dress <span class="token punctuation">|</span> blue <span class="token punctuation">|</span> 2 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> 7 <span class="token punctuation">|</span> t<span class="token punctuation">-</span>shirt <span class="token punctuation">|</span> white <span class="token punctuation">|</span> 2 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token keyword">SELECT</span> s<span class="token punctuation">.</span><span class="token operator">*</span> <span class="token keyword">FROM</span> person p <span class="token keyword">INNER</span> <span class="token keyword">JOIN</span> shirt s
<span class="token keyword">ON</span> s<span class="token punctuation">.</span><span class="token keyword">owner</span> <span class="token operator">=</span> p<span class="token punctuation">.</span>id
<span class="token keyword">WHERE</span> p<span class="token punctuation">.</span><span class="token keyword">name</span> <span class="token operator">LIKE</span> <span class="token string">'Lilliana%'</span>
<span class="token operator">AND</span> s<span class="token punctuation">.</span>color <span class="token operator"><></span> <span class="token string">'white'</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> id <span class="token punctuation">|</span> style <span class="token punctuation">|</span> color <span class="token punctuation">|</span> owner <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> 4 <span class="token punctuation">|</span> dress <span class="token punctuation">|</span> orange <span class="token punctuation">|</span> 2 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> 5 <span class="token punctuation">|</span> polo <span class="token punctuation">|</span> red <span class="token punctuation">|</span> 2 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> 6 <span class="token punctuation">|</span> dress <span class="token punctuation">|</span> blue <span class="token punctuation">|</span> 2 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span></code></pre>
</div>
<p>
When used in this fashion, the
<code class="literal">
REFERENCES
</code>
clause is not displayed in
the output of
<a class="link" href="show-create-table.html" title="15.7.7.11 SHOW CREATE TABLE Statement">
<code class="literal">
SHOW CREATE
TABLE
</code>
</a>
or
<a class="link" href="describe.html" title="15.8.1 DESCRIBE Statement">
<code class="literal">
DESCRIBE
</code>
</a>
:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa77859931"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SHOW</span> <span class="token keyword">CREATE</span> <span class="token keyword">TABLE</span> shirt\G
<span class="token output"><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span> 1. row <span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span>
Table<span class="token punctuation">:</span> shirt
Create Table<span class="token punctuation">:</span> CREATE TABLE `shirt` (
`id` smallint(5) unsigned NOT NULL auto_increment,
`style` enum('t-shirt','polo','dress') NOT NULL,
`color` enum('red','blue','orange','white','black') NOT NULL,
`owner` smallint(5) unsigned NOT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci</span></code></pre>
</div>
</li>
</ul>
</div>
<p>
For information about foreign key constraints, see
<a class="xref" href="create-table-foreign-keys.html" title="15.1.20.5 FOREIGN KEY Constraints">
Section 15.1.20.5, “FOREIGN KEY Constraints”
</a>
.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/replication-sbr-rbr.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="replication-sbr-rbr">
</a>
19.2.1.1 Advantages and Disadvantages of Statement-Based and Row-Based
Replication
</h4>
</div>
</div>
</div>
<a class="indexterm" name="idm46045138524096">
</a>
<a class="indexterm" name="idm46045138522640">
</a>
<p>
Each binary logging format has advantages and disadvantages. For
most users, the mixed replication format should provide the best
combination of data integrity and performance. If, however, you
want to take advantage of the features specific to the
statement-based or row-based replication format when performing
certain tasks, you can use the information in this section,
which provides a summary of their relative advantages and
disadvantages, to determine which is best for your needs.
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<a class="link" href="replication-sbr-rbr.html#replication-sbr-rbr-sbr-advantages" title="Advantages of statement-based replication">
Advantages
of statement-based replication
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="replication-sbr-rbr.html#replication-sbr-rbr-sbr-disadvantages" title="Disadvantages of statement-based replication">
Disadvantages
of statement-based replication
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="replication-sbr-rbr.html#replication-sbr-rbr-rbr-advantages" title="Advantages of row-based replication">
Advantages
of row-based replication
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="replication-sbr-rbr.html#replication-sbr-rbr-rbr-disadvantages" title="Disadvantages of row-based replication">
Disadvantages
of row-based replication
</a>
</p>
</li>
</ul>
</div>
<h5>
<a name="replication-sbr-rbr-sbr-advantages">
</a>
Advantages of statement-based replication
</h5>
<a class="indexterm" name="idm46045138510672">
</a>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
Proven technology.
</p>
</li>
<li class="listitem">
<p>
Less data written to log files. When updates or deletes
affect many rows, this results in
<span class="emphasis">
<em>
much
</em>
</span>
less storage space required for log files. This also means
that taking and restoring from backups can be accomplished
more quickly.
</p>
</li>
<li class="listitem">
<p>
Log files contain all statements that made any changes, so
they can be used to audit the database.
</p>
</li>
</ul>
</div>
<h5>
<a name="replication-sbr-rbr-sbr-disadvantages">
</a>
Disadvantages of statement-based replication
</h5>
<a class="indexterm" name="idm46045138504320">
</a>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<b>
Statements that are unsafe for SBR.
</b>
<a class="indexterm" name="idm46045138501664">
</a>
<a class="indexterm" name="idm46045138500144">
</a>
Not all statements which modify data (such as
<a class="link" href="insert.html" title="15.2.7 INSERT Statement">
<code class="literal">
INSERT
</code>
</a>
<a class="link" href="delete.html" title="15.2.2 DELETE Statement">
<code class="literal">
DELETE
</code>
</a>
,
<a class="link" href="update.html" title="15.2.17 UPDATE Statement">
<code class="literal">
UPDATE
</code>
</a>
, and
<a class="link" href="replace.html" title="15.2.12 REPLACE Statement">
<code class="literal">
REPLACE
</code>
</a>
statements) can be
replicated using statement-based replication. Any
nondeterministic behavior is difficult to replicate when
using statement-based replication. Examples of such Data
Modification Language (DML) statements include the
following:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
A statement that depends on a loadable function or
stored program that is nondeterministic, since the value
returned by such a function or stored program or depends
on factors other than the parameters supplied to it.
(Row-based replication, however, simply replicates the
value returned by the function or stored program, so its
effect on table rows and data is the same on both the
source and replica.) See
<a class="xref" href="replication-features-invoked.html" title="19.5.1.16 Replication of Invoked Features">
Section 19.5.1.16, “Replication of Invoked Features”
</a>
, for more
information.
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="delete.html" title="15.2.2 DELETE Statement">
<code class="literal">
DELETE
</code>
</a>
and
<a class="link" href="update.html" title="15.2.17 UPDATE Statement">
<code class="literal">
UPDATE
</code>
</a>
statements that
use a
<code class="literal">
LIMIT
</code>
clause without an
<code class="literal">
ORDER BY
</code>
are nondeterministic. See
<a class="xref" href="replication-features-limit.html" title="19.5.1.18 Replication and LIMIT">
Section 19.5.1.18, “Replication and LIMIT”
</a>
.
</p>
</li>
<li class="listitem">
<p>
Locking read statements
(
<a class="link" href="select.html" title="15.2.13 SELECT Statement">
<code class="literal">
SELECT ... FOR
UPDATE
</code>
</a>
and
<a class="link" href="select.html" title="15.2.13 SELECT Statement">
<code class="literal">
SELECT ... FOR
SHARE
</code>
</a>
) that use
<code class="literal">
NOWAIT
</code>
or
<code class="literal">
SKIP LOCKED
</code>
options. See
<a class="xref" href="innodb-locking-reads.html#innodb-locking-reads-nowait-skip-locked" title="Locking Read Concurrency with NOWAIT and SKIP LOCKED">
Locking Read Concurrency with NOWAIT and SKIP LOCKED
</a>
.
</p>
</li>
<li class="listitem">
<p>
Deterministic loadable functions must be applied on the
replicas.
</p>
</li>
<li class="listitem">
<p>
Statements using any of the following functions cannot
be replicated properly using statement-based
replication:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: square; ">
<li class="listitem">
<p>
<a class="link" href="string-functions.html#function_load-file">
<code class="literal">
LOAD_FILE()
</code>
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="miscellaneous-functions.html#function_uuid">
<code class="literal">
UUID()
</code>
</a>
,
<a class="link" href="miscellaneous-functions.html#function_uuid-short">
<code class="literal">
UUID_SHORT()
</code>
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="information-functions.html#function_user">
<code class="literal">
USER()
</code>
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="information-functions.html#function_found-rows">
<code class="literal">
FOUND_ROWS()
</code>
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="date-and-time-functions.html#function_sysdate">
<code class="literal">
SYSDATE()
</code>
</a>
(unless
both the source and the replica are started with the
<a class="link" href="server-options.html#option_mysqld_sysdate-is-now">
<code class="option">
--sysdate-is-now
</code>
</a>
option)
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="locking-functions.html#function_get-lock">
<code class="literal">
GET_LOCK()
</code>
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="locking-functions.html#function_is-free-lock">
<code class="literal">
IS_FREE_LOCK()
</code>
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="locking-functions.html#function_is-used-lock">
<code class="literal">
IS_USED_LOCK()
</code>
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="mathematical-functions.html#function_rand">
<code class="literal">
RAND()
</code>
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="locking-functions.html#function_release-lock">
<code class="literal">
RELEASE_LOCK()
</code>
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="replication-functions-synchronization.html#function_source-pos-wait">
<code class="literal">
SOURCE_POS_WAIT()
</code>
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="miscellaneous-functions.html#function_sleep">
<code class="literal">
SLEEP()
</code>
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="information-functions.html#function_version">
<code class="literal">
VERSION()
</code>
</a>
</p>
</li>
</ul>
</div>
<p>
However, all other functions are replicated correctly
using statement-based replication, including
<a class="link" href="date-and-time-functions.html#function_now">
<code class="literal">
NOW()
</code>
</a>
and so forth.
</p>
<p>
For more information, see
<a class="xref" href="replication-features-functions.html" title="19.5.1.14 Replication and System Functions">
Section 19.5.1.14, “Replication and System Functions”
</a>
.
</p>
</li>
</ul>
</div>
<p>
Statements that cannot be replicated correctly using
statement-based replication are logged with a warning like
the one shown here:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-none"><div class="docs-select-all right" id="sa45951381"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-none">[Warning] Statement is not safe to log in statement format.</code></pre>
</div>
<p>
A similar warning is also issued to the client in such
cases. The client can display it using
<a class="link" href="show-warnings.html" title="15.7.7.42 SHOW WARNINGS Statement">
<code class="literal">
SHOW WARNINGS
</code>
</a>
.
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="insert.html" title="15.2.7 INSERT Statement">
<code class="literal">
INSERT ...
SELECT
</code>
</a>
requires a greater number of row-level
locks than with row-based replication.
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="update.html" title="15.2.17 UPDATE Statement">
<code class="literal">
UPDATE
</code>
</a>
statements that
require a table scan (because no index is used in the
<code class="literal">
WHERE
</code>
clause) must lock a greater number
of rows than with row-based replication.
</p>
</li>
<li class="listitem">
<p>
For
<a class="link" href="innodb-storage-engine.html" title="Chapter 17 The InnoDB Storage Engine">
<code class="literal">
InnoDB
</code>
</a>
: An
<a class="link" href="insert.html" title="15.2.7 INSERT Statement">
<code class="literal">
INSERT
</code>
</a>
statement that uses
<code class="literal">
AUTO_INCREMENT
</code>
blocks other
nonconflicting
<a class="link" href="insert.html" title="15.2.7 INSERT Statement">
<code class="literal">
INSERT
</code>
</a>
statements.
</p>
</li>
<li class="listitem">
<p>
For complex statements, the statement must be evaluated and
executed on the replica before the rows are updated or
inserted. With row-based replication, the replica only has
to modify the affected rows, not execute the full statement.
</p>
</li>
<li class="listitem">
<p>
If there is an error in evaluation on the replica,
particularly when executing complex statements,
statement-based replication may slowly increase the margin
of error across the affected rows over time. See
<a class="xref" href="replication-features-errors.html" title="19.5.1.29 Replica Errors During Replication">
Section 19.5.1.29, “Replica Errors During Replication”
</a>
.
</p>
</li>
<li class="listitem">
<p>
Stored functions execute with the same
<a class="link" href="date-and-time-functions.html#function_now">
<code class="literal">
NOW()
</code>
</a>
value as the calling
statement. However, this is not true of stored procedures.
</p>
</li>
<li class="listitem">
<p>
Deterministic loadable functions must be applied on the
replicas.
</p>
</li>
<li class="listitem">
<p>
Table definitions must be (nearly) identical on source and
replica. See
<a class="xref" href="replication-features-differing-tables.html" title="19.5.1.9 Replication with Differing Table Definitions on Source and Replica">
Section 19.5.1.9, “Replication with Differing Table Definitions on Source and Replica”
</a>
, for
more information.
</p>
</li>
<li class="listitem">
<p>
DML operations that read data from MySQL grant tables
(through a join list or subquery) but do not modify them are
performed as non-locking reads on the MySQL grant tables and
are therefore not safe for statement-based replication. For
more information, see
<a class="xref" href="grant-tables.html#grant-tables-concurrency" title="Grant Table Concurrency">
Grant Table Concurrency
</a>
.
</p>
</li>
</ul>
</div>
<h5>
<a name="replication-sbr-rbr-rbr-advantages">
</a>
Advantages of row-based replication
</h5>
<a class="indexterm" name="idm46045138421008">
</a>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
All changes can be replicated. This is the safest form of
replication.
</p>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Note
</div>
<p>
Statements that update the information in the
<code class="literal">
mysql
</code>
system schema, such as
<a class="link" href="grant.html" title="15.7.1.6 GRANT Statement">
<code class="literal">
GRANT
</code>
</a>
,
<a class="link" href="revoke.html" title="15.7.1.8 REVOKE Statement">
<code class="literal">
REVOKE
</code>
</a>
and the manipulation
of triggers, stored routines (including stored
procedures), and views, are all replicated to replicas
using statement-based replication.
</p>
<p>
For statements such as
<a class="link" href="create-table.html" title="15.1.20 CREATE TABLE Statement">
<code class="literal">
CREATE TABLE
... SELECT
</code>
</a>
, a
<code class="literal">
CREATE
</code>
statement is generated from the table definition and
replicated using statement-based format, while the row
insertions are replicated using row-based format.
</p>
</div>
</li>
<li class="listitem">
<p>
Fewer row locks are required on the source, which thus
achieves higher concurrency, for the following types of
statements:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
<a class="link" href="insert-select.html" title="15.2.7.1 INSERT ... SELECT Statement">
<code class="literal">
INSERT
... SELECT
</code>
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="insert.html" title="15.2.7 INSERT Statement">
<code class="literal">
INSERT
</code>
</a>
statements with
<code class="literal">
AUTO_INCREMENT
</code>
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="update.html" title="15.2.17 UPDATE Statement">
<code class="literal">
UPDATE
</code>
</a>
or
<a class="link" href="delete.html" title="15.2.2 DELETE Statement">
<code class="literal">
DELETE
</code>
</a>
statements with
<code class="literal">
WHERE
</code>
clauses that do not use keys or
do not change most of the examined rows.
</p>
</li>
</ul>
</div>
</li>
<li class="listitem">
<p>
Fewer row locks are required on the replica for any
<a class="link" href="insert.html" title="15.2.7 INSERT Statement">
<code class="literal">
INSERT
</code>
</a>
,
<a class="link" href="update.html" title="15.2.17 UPDATE Statement">
<code class="literal">
UPDATE
</code>
</a>
, or
<a class="link" href="delete.html" title="15.2.2 DELETE Statement">
<code class="literal">
DELETE
</code>
</a>
statement.
</p>
</li>
</ul>
</div>
<h5>
<a name="replication-sbr-rbr-rbr-disadvantages">
</a>
Disadvantages of row-based replication
</h5>
<a class="indexterm" name="idm46045138395600">
</a>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
RBR can generate more data that must be logged. To replicate
a DML statement (such as an
<a class="link" href="update.html" title="15.2.17 UPDATE Statement">
<code class="literal">
UPDATE
</code>
</a>
or
<a class="link" href="delete.html" title="15.2.2 DELETE Statement">
<code class="literal">
DELETE
</code>
</a>
statement),
statement-based replication writes only the statement to the
binary log. By contrast, row-based replication writes each
changed row to the binary log. If the statement changes many
rows, row-based replication may write significantly more
data to the binary log; this is true even for statements
that are rolled back. This also means that making and
restoring a backup can require more time. In addition, the
binary log is locked for a longer time to write the data,
which may cause concurrency problems. Use
<a class="link" href="replication-options-binary-log.html#sysvar_binlog_row_image">
<code class="literal">
binlog_row_image=minimal
</code>
</a>
to
reduce the disadvantage considerably.
</p>
</li>
<li class="listitem">
<p>
Deterministic loadable functions that generate large
<a class="link" href="blob.html" title="13.3.4 The BLOB and TEXT Types">
<code class="literal">
BLOB
</code>
</a>
values take longer to
replicate with row-based replication than with
statement-based replication. This is because the
<a class="link" href="blob.html" title="13.3.4 The BLOB and TEXT Types">
<code class="literal">
BLOB
</code>
</a>
column value is logged,
rather than the statement generating the data.
</p>
</li>
<li class="listitem">
<p>
You cannot see on the replica what statements were received
from the source and executed. However, you can see what data
was changed using
<a class="link" href="mysqlbinlog.html" title="6.6.9 mysqlbinlog — Utility for Processing Binary Log Files">
<span class="command">
<strong>
mysqlbinlog
</strong>
</span>
</a>
with the
options
<a class="link" href="mysqlbinlog.html#option_mysqlbinlog_base64-output">
<code class="option">
--base64-output=DECODE-ROWS
</code>
</a>
and
<a class="link" href="mysqlbinlog.html#option_mysqlbinlog_verbose">
<code class="option">
--verbose
</code>
</a>
.
</p>
<p>
Alternatively, use the
<a class="link" href="replication-options-binary-log.html#sysvar_binlog_rows_query_log_events">
<code class="literal">
binlog_rows_query_log_events
</code>
</a>
variable, which if enabled adds a
<code class="literal">
Rows_query
</code>
event with the statement to
<a class="link" href="mysqlbinlog.html" title="6.6.9 mysqlbinlog — Utility for Processing Binary Log Files">
<span class="command">
<strong>
mysqlbinlog
</strong>
</span>
</a>
output when the
<code class="literal">
-vv
</code>
option is used.
</p>
</li>
<li class="listitem">
<p>
For tables using the
<a class="link" href="myisam-storage-engine.html" title="18.2 The MyISAM Storage Engine">
<code class="literal">
MyISAM
</code>
</a>
storage engine, a stronger lock is required on the replica
for
<a class="link" href="insert.html" title="15.2.7 INSERT Statement">
<code class="literal">
INSERT
</code>
</a>
statements when
applying them as row-based events to the binary log than
when applying them as statements. This means that concurrent
inserts on
<a class="link" href="myisam-storage-engine.html" title="18.2 The MyISAM Storage Engine">
<code class="literal">
MyISAM
</code>
</a>
tables are
not supported when using row-based replication.
</p>
</li>
</ul>
</div>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/replication-rules-channel-based-filters.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="replication-rules-channel-based-filters">
</a>
19.2.5.4 Replication Channel Based Filters
</h4>
</div>
</div>
</div>
<a class="indexterm" name="idm46045137337184">
</a>
<p>
This section explains how to work with replication filters when
multiple replication channels exist, for example in a
multi-source replication topology. Replication filters can be
global or specific to a channel, enabling you to configure
multi-source replicas with replication filters on specific
replication channels. Channel specific replication filters are
particularly useful in a multi-source replication topology when
the same database or table is present on multiple sources, and
the replica is only required to replicate it from one source.
</p>
<p>
For instructions to set up replication channels, see
<a class="xref" href="replication-multi-source.html" title="19.1.5 MySQL Multi-Source Replication">
Section 19.1.5, “MySQL Multi-Source Replication”
</a>
, and for more
information on how they work, see
<a class="xref" href="replication-channels.html" title="19.2.2 Replication Channels">
Section 19.2.2, “Replication Channels”
</a>
.
</p>
<div class="important" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Important
</div>
<p>
Each channel on a multi-source replica must replicate from a
different source. You cannot set up multiple replication
channels from a single replica to a single source, even if you
use replication filters to select different data to replicate
on each channel. This is because the server IDs of replicas
must be unique in a replication topology. The source
distinguishes replicas only by their server IDs, not by the
names of the replication channels, so it cannot recognize
different replication channels from the same replica.
</p>
</div>
<div class="important" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Important
</div>
<p>
On a MySQL server instance that is configured for Group
Replication, channel specific replication filters can be used
on replication channels that are not directly involved with
Group Replication, such as where a group member also acts as a
replica to a source that is outside the group. They cannot be
used on the
<code class="literal">
group_replication_applier
</code>
or
<code class="literal">
group_replication_recovery
</code>
channels.
Filtering on these channels would make the group unable to
reach agreement on a consistent state.
</p>
</div>
<div class="important" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Important
</div>
<p>
For a multi-source replica in a diamond topology (where the
replica replicates from two or more sources, which in turn
replicate from a common source), when GTID-based replication
is in use, ensure that any replication filters or other
channel configuration are identical on all channels on the
multi-source replica. With GTID-based replication, filters are
applied only to the transaction data, and GTIDs are not
filtered out. This happens so that a replica’s GTID set
stays consistent with the source’s, meaning GTID
auto-positioning can be used without re-acquiring filtered out
transactions each time. In the case where the downstream
replica is multi-source and receives the same transaction from
multiple sources in a diamond topology, the downstream replica
now has multiple versions of the transaction, and the result
depends on which channel applies the transaction first. The
second channel to attempt it skips the transaction using GTID
auto-skip, because the transaction’s GTID was added to the
<a class="link" href="replication-options-gtids.html#sysvar_gtid_executed">
<code class="literal">
gtid_executed
</code>
</a>
set by the
first channel. With identical filtering on the channels, there
is no problem because all versions of the transaction contain
the same data, so the results are the same. However, with
different filtering on the channels, the database can become
inconsistent and replication can hang.
</p>
</div>
<div class="simplesect">
<div class="titlepage">
<div>
<div class="simple">
<h5 class="title">
<a name="replication-rules-channel-overview">
</a>
Overview of Replication Filters and Channels
</h5>
</div>
</div>
</div>
<p>
When multiple replication channels exist, for example in a
multi-source replication topology, replication filters are
applied as follows:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
Any global replication filter specified is added to the
global replication filters of the filter type
(
<code class="literal">
do_db
</code>
,
<code class="literal">
do_ignore_table
</code>
, and so on).
</p>
</li>
<li class="listitem">
<p>
Any channel specific replication filter adds the filter to
the specified channel’s replication filters for the
specified filter type.
</p>
</li>
<li class="listitem">
<p>
Each replication channel copies global replication filters
to its channel specific replication filters if no channel
specific replication filter of this type is configured.
</p>
</li>
<li class="listitem">
<p>
Each channel uses its channel specific replication filters
to filter the replication stream.
</p>
</li>
</ul>
</div>
<p>
The syntax to create channel specific replication filters
extends the existing SQL statements and command options. When
a replication channel is not specified the global replication
filter is configured to ensure backwards compatibility. The
<a class="link" href="change-replication-filter.html" title="15.4.2.1 CHANGE REPLICATION FILTER Statement">
<code class="literal">
CHANGE REPLICATION FILTER
</code>
</a>
statement supports the
<code class="literal">
FOR CHANNEL
</code>
clause
to configure channel specific filters online. The
<code class="literal">
--replicate-*
</code>
command options to configure
filters can specify a replication channel using the form
<code class="literal">
--replicate-
<em class="replaceable">
<code>
filter_type
</code>
</em>
=
<em class="replaceable">
<code>
channel_name
</code>
</em>
:
<em class="replaceable">
<code>
filter_details
</code>
</em>
</code>
.
Suppose channels
<code class="literal">
channel_1
</code>
and
<code class="literal">
channel_2
</code>
exist before the server starts;
in this case, starting the replica with the command line
options
<a class="link" href="replication-options-replica.html#option_mysqld_replicate-do-db">
<code class="option">
--replicate-do-db=db1
</code>
</a>
<a class="link" href="replication-options-replica.html#option_mysqld_replicate-do-db">
<code class="option">
--replicate-do-db=channel_1:db2
</code>
</a>
<a class="link" href="replication-options-replica.html#option_mysqld_replicate-do-db">
<code class="option">
--replicate-do-db=db3
</code>
</a>
<a class="link" href="replication-options-replica.html#option_mysqld_replicate-ignore-db">
<code class="option">
--replicate-ignore-db=db4
</code>
</a>
<a class="link" href="replication-options-replica.html#option_mysqld_replicate-ignore-db">
<code class="option">
--replicate-ignore-db=channel_2:db5
</code>
</a>
<a class="link" href="replication-options-replica.html#option_mysqld_replicate-wild-do-table">
<code class="option">
--replicate-wild-do-table=channel_1:db6.t1%
</code>
</a>
would result in:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<span class="emphasis">
<em>
Global replication filters
</em>
</span>
:
<code class="literal">
do_db=db1,db3
</code>
;
<code class="literal">
ignore_db=db4
</code>
</p>
</li>
<li class="listitem">
<p>
<span class="emphasis">
<em>
Channel specific filters on
channel_1
</em>
</span>
:
<code class="literal">
do_db=db2
</code>
;
<code class="literal">
ignore_db=db4
</code>
;
<code class="literal">
wild-do-table=db6.t1%
</code>
</p>
</li>
<li class="listitem">
<p>
<span class="emphasis">
<em>
Channel specific filters on
channel_2
</em>
</span>
:
<code class="literal">
do_db=db1,db3
</code>
;
<code class="literal">
ignore_db=db5
</code>
</p>
</li>
</ul>
</div>
<p>
These same rules could be applied at startup when included in
the replica's
<code class="filename">
my.cnf
</code>
file, like
this:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-ini"><div class="docs-select-all right" id="sa36120525"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-ini"><span class="token constant">replicate-do-db</span><span class="token attr-value"><span class="token punctuation">=</span>db1</span>
<span class="token constant">replicate-do-db</span><span class="token attr-value"><span class="token punctuation">=</span>channel_1:db2</span>
<span class="token constant">replicate-ignore-db</span><span class="token attr-value"><span class="token punctuation">=</span>db4</span>
<span class="token constant">replicate-ignore-db</span><span class="token attr-value"><span class="token punctuation">=</span>channel_2:db5</span>
<span class="token constant">replicate-wild-do-table</span><span class="token attr-value"><span class="token punctuation">=</span>db6.channel_1.t1%</span></code></pre>
</div>
<p>
To monitor the replication filters in such a setup use the
<a class="link" href="performance-schema-replication-applier-global-filters-table.html" title="29.12.11.4 The replication_applier_global_filters Table">
<code class="literal">
replication_applier_global_filters
</code>
</a>
and
<a class="link" href="performance-schema-replication-applier-filters-table.html" title="29.12.11.3 The replication_applier_filters Table">
<code class="literal">
replication_applier_filters
</code>
</a>
tables.
</p>
</div>
<div class="simplesect">
<div class="titlepage">
<div>
<div class="simple">
<h5 class="title">
<a name="replication-rules-channel-replication-filter-options">
</a>
Configuring Channel Specific Replication Filters at Startup
</h5>
</div>
</div>
</div>
<p>
The replication filter related command options can take an
optional
<em class="replaceable">
<code>
channel
</code>
</em>
followed by a
colon, followed by the filter specification. The first colon
is interpreted as a separator, subsequent colons are
interpreted as literal colons. The following command options
support channel specific replication filters using this
format:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<code class="literal">
--replicate-do-db=
<em class="replaceable">
<code>
channel
</code>
</em>
:
<em class="replaceable">
<code>
database_id
</code>
</em>
</code>
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
--replicate-ignore-db=
<em class="replaceable">
<code>
channel
</code>
</em>
:
<em class="replaceable">
<code>
database_id
</code>
</em>
</code>
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
--replicate-do-table=
<em class="replaceable">
<code>
channel
</code>
</em>
:
<em class="replaceable">
<code>
table_id
</code>
</em>
</code>
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
--replicate-ignore-table=
<em class="replaceable">
<code>
channel
</code>
</em>
:
<em class="replaceable">
<code>
table_id
</code>
</em>
</code>
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
--replicate-rewrite-db=
<em class="replaceable">
<code>
channel
</code>
</em>
:
<em class="replaceable">
<code>
db1-db2
</code>
</em>
</code>
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
--replicate-wild-do-table=
<em class="replaceable">
<code>
channel
</code>
</em>
:
<em class="replaceable">
<code>
table
</code>
</em>
<em class="replaceable">
<code>
pattern
</code>
</em>
</code>
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
--replicate-wild-ignore-table=
<em class="replaceable">
<code>
channel
</code>
</em>
:
<em class="replaceable">
<code>
table
</code>
</em>
<em class="replaceable">
<code>
pattern
</code>
</em>
</code>
</p>
</li>
</ul>
</div>
<p>
All of the options just listed can be used in the
replica's
<code class="filename">
my.cnf
</code>
file, as with most
other MySQL server startup options, by omitting the two
leading dashes. See
<a class="xref" href="replication-rules-channel-based-filters.html#replication-rules-channel-overview" title="Overview of Replication Filters and Channels">
Overview of Replication Filters and Channels
</a>
, for a
brief example, as well as
<a class="xref" href="option-files.html" title="6.2.2.2 Using Option Files">
Section 6.2.2.2, “Using Option Files”
</a>
.
</p>
<p>
If you use a colon but do not specify a
<em class="replaceable">
<code>
channel
</code>
</em>
for the filter option, for
example
<code class="option">
--replicate-do-db=:
<em class="replaceable">
<code>
database_id
</code>
</em>
</code>
,
the option configures the replication filter for the default
replication channel. The default replication channel is the
replication channel which always exists once replication has
been started, and differs from multi-source replication
channels which you create manually. When neither the colon nor
a
<em class="replaceable">
<code>
channel
</code>
</em>
is specified the option
configures the global replication filters, for example
<code class="option">
--replicate-do-db=
<em class="replaceable">
<code>
database_id
</code>
</em>
</code>
configures the global
<a class="link" href="replication-options-replica.html#option_mysqld_replicate-do-db">
<code class="option">
--replicate-do-db
</code>
</a>
filter.
</p>
<p>
If you configure multiple
<code class="literal">
rewrite-db=
<em class="replaceable">
<code>
from_name
</code>
</em>
->
<em class="replaceable">
<code>
to_name
</code>
</em>
</code>
options with the same
<em class="replaceable">
<code>
from_name
</code>
</em>
database, all filters are added together (put into the
<code class="literal">
rewrite_do
</code>
list) and the first one takes
effect.
</p>
<p>
The
<em class="replaceable">
<code>
pattern
</code>
</em>
used for the
<code class="option">
--replicate-wild-*-table
</code>
options can include
any characters allowed in identifiers as well as the wildcards
<code class="literal">
%
</code>
and
<code class="literal">
_
</code>
. These work the
same way as when used with the
<a class="link" href="string-comparison-functions.html#operator_like">
<code class="literal">
LIKE
</code>
</a>
operator; for example,
<code class="literal">
tbl%
</code>
matches any table name beginning with
<code class="literal">
tbl
</code>
, and
<code class="literal">
tbl_
</code>
matches
any table name matching
<code class="literal">
tbl
</code>
plus one
additional character.
</p>
</div>
<div class="simplesect">
<div class="titlepage">
<div>
<div class="simple">
<h5 class="title">
<a name="replication-rules-channel-change-replication-filter">
</a>
Changing Channel Specific Replication Filters Online
</h5>
</div>
</div>
</div>
<p>
In addition to the
<code class="option">
--replicate-*
</code>
options,
replication filters can be configured using the
<a class="link" href="change-replication-filter.html" title="15.4.2.1 CHANGE REPLICATION FILTER Statement">
<code class="literal">
CHANGE REPLICATION FILTER
</code>
</a>
statement. This removes the need to restart the server, but
the replication SQL thread must be stopped while making the
change. To make this statement apply the filter to a specific
channel, use the
<code class="literal">
FOR CHANNEL
<em class="replaceable">
<code>
channel
</code>
</em>
</code>
clause. For
example:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-sql"><div class="docs-select-all right" id="sa25288439"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">CHANGE</span> <span class="token keyword">REPLICATION</span> <span class="token keyword">FILTER</span> <span class="token keyword">REPLICATE_DO_DB</span><span class="token operator">=</span><span class="token punctuation">(</span>db1<span class="token punctuation">)</span> <span class="token keyword">FOR</span> <span class="token keyword">CHANNEL</span> channel_1<span class="token punctuation">;</span></code></pre>
</div>
<p>
When a
<code class="literal">
FOR CHANNEL
</code>
clause is provided, the
statement acts on the specified channel's replication
filters. If multiple types of filters
(
<code class="literal">
do_db
</code>
,
<code class="literal">
do_ignore_table
</code>
,
<code class="literal">
wild_do_table
</code>
, and so on) are specified,
only the specified filter types are replaced by the statement.
In a replication topology with multiple channels, for example
on a multi-source replica, when no
<code class="literal">
FOR
CHANNEL
</code>
clause is provided, the statement acts on
the global replication filters and all channels’ replication
filters, using a similar logic as the
<code class="literal">
FOR
CHANNEL
</code>
case. For more information see
<a class="xref" href="change-replication-filter.html" title="15.4.2.1 CHANGE REPLICATION FILTER Statement">
Section 15.4.2.1, “CHANGE REPLICATION FILTER Statement”
</a>
.
</p>
</div>
<div class="simplesect">
<div class="titlepage">
<div>
<div class="simple">
<h5 class="title">
<a name="replication-rules-channel-removing">
</a>
Removing Channel Specific Replication Filters
</h5>
</div>
</div>
</div>
<p>
When channel specific replication filters have been
configured, you can remove the filter by issuing an empty
filter type statement. For example to remove all
<code class="literal">
REPLICATE_REWRITE_DB
</code>
filters from a
replication channel named
<code class="literal">
channel_1
</code>
issue:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-sql"><div class="docs-select-all right" id="sa66973850"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">CHANGE</span> <span class="token keyword">REPLICATION</span> <span class="token keyword">FILTER</span> <span class="token keyword">REPLICATE_REWRITE_DB</span><span class="token operator">=</span><span class="token punctuation">(</span><span class="token punctuation">)</span> <span class="token keyword">FOR</span> <span class="token keyword">CHANNEL</span> channel_1<span class="token punctuation">;</span></code></pre>
</div>
<p>
Any
<code class="literal">
REPLICATE_REWRITE_DB
</code>
filters previously
configured, using either command options or
<a class="link" href="change-replication-filter.html" title="15.4.2.1 CHANGE REPLICATION FILTER Statement">
<code class="literal">
CHANGE REPLICATION FILTER
</code>
</a>
, are
removed.
</p>
<p>
The
<a class="link" href="reset-replica.html" title="15.4.2.3 RESET REPLICA Statement">
<code class="literal">
RESET
REPLICA ALL
</code>
</a>
statement removes channel specific
replication filters that were set on channels deleted by the
statement. When the deleted channel or channels are recreated,
any global replication filters specified for the replica are
copied to them, and no channel specific replication filters
are applied.
</p>
</div>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/show-collation.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="show-collation">
</a>
15.7.7.5 SHOW COLLATION Statement
</h4>
</div>
</div>
</div>
<a class="indexterm" name="idm46045171110592">
</a>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa93033195"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">SHOW</span> <span class="token keyword">COLLATION</span>
<span class="token punctuation">[</span><span class="token operator">LIKE</span> <span class="token string">'<em class="replaceable">pattern</em>'</span> <span class="token operator">|</span> <span class="token keyword">WHERE</span> <em class="replaceable">expr</em><span class="token punctuation">]</span></code></pre>
</div>
<p>
This statement lists collations supported by the server. By
default, the output from
<a class="link" href="show-collation.html" title="15.7.7.5 SHOW COLLATION Statement">
<code class="literal">
SHOW
COLLATION
</code>
</a>
includes all available collations. The
<a class="link" href="string-comparison-functions.html#operator_like">
<code class="literal">
LIKE
</code>
</a>
clause, if present, indicates
which collation names to match. The
<code class="literal">
WHERE
</code>
clause can be given to select rows using more general
conditions, as discussed in
<a class="xref" href="extended-show.html" title="28.8 Extensions to SHOW Statements">
Section 28.8, “Extensions to SHOW Statements”
</a>
. For
example:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa14418789"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SHOW</span> <span class="token keyword">COLLATION</span> <span class="token keyword">WHERE</span> <span class="token keyword">Charset</span> <span class="token operator">=</span> <span class="token string">'latin1'</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> Collation <span class="token punctuation">|</span> Charset <span class="token punctuation">|</span> Id <span class="token punctuation">|</span> Default <span class="token punctuation">|</span> Compiled <span class="token punctuation">|</span> Sortlen <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> latin1_german1_ci <span class="token punctuation">|</span> latin1 <span class="token punctuation">|</span> 5 <span class="token punctuation">|</span> <span class="token punctuation">|</span> Yes <span class="token punctuation">|</span> 1 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> latin1_swedish_ci <span class="token punctuation">|</span> latin1 <span class="token punctuation">|</span> 8 <span class="token punctuation">|</span> Yes <span class="token punctuation">|</span> Yes <span class="token punctuation">|</span> 1 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> latin1_danish_ci <span class="token punctuation">|</span> latin1 <span class="token punctuation">|</span> 15 <span class="token punctuation">|</span> <span class="token punctuation">|</span> Yes <span class="token punctuation">|</span> 1 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> latin1_german2_ci <span class="token punctuation">|</span> latin1 <span class="token punctuation">|</span> 31 <span class="token punctuation">|</span> <span class="token punctuation">|</span> Yes <span class="token punctuation">|</span> 2 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> latin1_bin <span class="token punctuation">|</span> latin1 <span class="token punctuation">|</span> 47 <span class="token punctuation">|</span> <span class="token punctuation">|</span> Yes <span class="token punctuation">|</span> 1 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> latin1_general_ci <span class="token punctuation">|</span> latin1 <span class="token punctuation">|</span> 48 <span class="token punctuation">|</span> <span class="token punctuation">|</span> Yes <span class="token punctuation">|</span> 1 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> latin1_general_cs <span class="token punctuation">|</span> latin1 <span class="token punctuation">|</span> 49 <span class="token punctuation">|</span> <span class="token punctuation">|</span> Yes <span class="token punctuation">|</span> 1 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> latin1_spanish_ci <span class="token punctuation">|</span> latin1 <span class="token punctuation">|</span> 94 <span class="token punctuation">|</span> <span class="token punctuation">|</span> Yes <span class="token punctuation">|</span> 1 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span></code></pre>
</div>
<p>
<a class="link" href="show-collation.html" title="15.7.7.5 SHOW COLLATION Statement">
<code class="literal">
SHOW COLLATION
</code>
</a>
output has these
columns:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<code class="literal">
Collation
</code>
</p>
<p>
The collation name.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Charset
</code>
</p>
<p>
The name of the character set with which the collation is
associated.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Id
</code>
</p>
<p>
The collation ID.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Default
</code>
</p>
<p>
Whether the collation is the default for its character set.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Compiled
</code>
</p>
<p>
Whether the character set is compiled into the server.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Sortlen
</code>
</p>
<p>
This is related to the amount of memory required to sort
strings expressed in the character set.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Pad_attribute
</code>
</p>
<p>
The collation pad attribute, one of
<code class="literal">
NO
PAD
</code>
or
<code class="literal">
PAD SPACE
</code>
. This
attribute affects whether trailing spaces are significant in
string comparisons; for more information, see
<a class="xref" href="charset-binary-collations.html#charset-binary-collations-trailing-space-comparisons" title="Trailing Space Handling in Comparisons">
Trailing Space Handling in Comparisons
</a>
.
</p>
</li>
</ul>
</div>
<p>
To see the default collation for each character set, use the
following statement.
<code class="literal">
Default
</code>
is a reserved
word, so to use it as an identifier, it must be quoted as such:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa83883740"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SHOW</span> <span class="token keyword">COLLATION</span> <span class="token keyword">WHERE</span> <span class="token punctuation">`</span><span class="token keyword">Default</span><span class="token punctuation">`</span> <span class="token operator">=</span> <span class="token string">'Yes'</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> Collation <span class="token punctuation">|</span> Charset <span class="token punctuation">|</span> Id <span class="token punctuation">|</span> Default <span class="token punctuation">|</span> Compiled <span class="token punctuation">|</span> Sortlen <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> big5_chinese_ci <span class="token punctuation">|</span> big5 <span class="token punctuation">|</span> 1 <span class="token punctuation">|</span> Yes <span class="token punctuation">|</span> Yes <span class="token punctuation">|</span> 1 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> dec8_swedish_ci <span class="token punctuation">|</span> dec8 <span class="token punctuation">|</span> 3 <span class="token punctuation">|</span> Yes <span class="token punctuation">|</span> Yes <span class="token punctuation">|</span> 1 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> cp850_general_ci <span class="token punctuation">|</span> cp850 <span class="token punctuation">|</span> 4 <span class="token punctuation">|</span> Yes <span class="token punctuation">|</span> Yes <span class="token punctuation">|</span> 1 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> hp8_english_ci <span class="token punctuation">|</span> hp8 <span class="token punctuation">|</span> 6 <span class="token punctuation">|</span> Yes <span class="token punctuation">|</span> Yes <span class="token punctuation">|</span> 1 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> koi8r_general_ci <span class="token punctuation">|</span> koi8r <span class="token punctuation">|</span> 7 <span class="token punctuation">|</span> Yes <span class="token punctuation">|</span> Yes <span class="token punctuation">|</span> 1 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> latin1_swedish_ci <span class="token punctuation">|</span> latin1 <span class="token punctuation">|</span> 8 <span class="token punctuation">|</span> Yes <span class="token punctuation">|</span> Yes <span class="token punctuation">|</span> 1 <span class="token punctuation">|</span></span>
<span class="token punctuation">.</span><span class="token punctuation">.</span><span class="token punctuation">.</span></code></pre>
</div>
<p>
Collation information is also available from the
<code class="literal">
INFORMATION_SCHEMA
</code>
<a class="link" href="information-schema-collations-table.html" title="28.3.6 The INFORMATION_SCHEMA COLLATIONS Table">
<code class="literal">
COLLATIONS
</code>
</a>
table. See
<a class="xref" href="information-schema-collations-table.html" title="28.3.6 The INFORMATION_SCHEMA COLLATIONS Table">
Section 28.3.6, “The INFORMATION_SCHEMA COLLATIONS Table”
</a>
.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/signal.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="signal">
</a>
15.6.7.5 SIGNAL Statement
</h4>
</div>
</div>
</div>
<a class="indexterm" name="idm46045175667120">
</a>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa59702304"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">SIGNAL</span> <em class="replaceable">condition_value</em>
<span class="token punctuation">[</span><span class="token keyword">SET</span> <em class="replaceable">signal_information_item</em>
<span class="token punctuation">[</span><span class="token punctuation">,</span> <em class="replaceable">signal_information_item</em><span class="token punctuation">]</span> <span class="token punctuation">.</span><span class="token punctuation">.</span><span class="token punctuation">.</span><span class="token punctuation">]</span>
<em class="replaceable">condition_value</em>: {
<span class="token keyword">SQLSTATE</span> <span class="token punctuation">[</span><span class="token keyword">VALUE</span><span class="token punctuation">]</span> <em class="replaceable">sqlstate_value</em>
<span class="token operator">|</span> <em class="replaceable">condition_name</em>
}
<em class="replaceable">signal_information_item</em>:
<em class="replaceable">condition_information_item_name</em> <span class="token operator">=</span> <em class="replaceable">simple_value_specification</em>
<em class="replaceable">condition_information_item_name</em>: {
<span class="token keyword">CLASS_ORIGIN</span>
<span class="token operator">|</span> <span class="token keyword">SUBCLASS_ORIGIN</span>
<span class="token operator">|</span> <span class="token keyword">MESSAGE_TEXT</span>
<span class="token operator">|</span> <span class="token keyword">MYSQL_ERRNO</span>
<span class="token operator">|</span> <span class="token keyword">CONSTRAINT_CATALOG</span>
<span class="token operator">|</span> <span class="token keyword">CONSTRAINT_SCHEMA</span>
<span class="token operator">|</span> <span class="token keyword">CONSTRAINT_NAME</span>
<span class="token operator">|</span> <span class="token keyword">CATALOG_NAME</span>
<span class="token operator">|</span> <span class="token keyword">SCHEMA_NAME</span>
<span class="token operator">|</span> <span class="token keyword">TABLE_NAME</span>
<span class="token operator">|</span> <span class="token keyword">COLUMN_NAME</span>
<span class="token operator">|</span> <span class="token keyword">CURSOR_NAME</span>
}
<em class="replaceable">condition_name</em><span class="token punctuation">,</span> <em class="replaceable">simple_value_specification</em>:
<span class="token punctuation">(</span>see <span class="token keyword">following</span> discussion<span class="token punctuation">)</span></code></pre>
</div>
<p>
<a class="link" href="signal.html" title="15.6.7.5 SIGNAL Statement">
<code class="literal">
SIGNAL
</code>
</a>
is the way to
<span class="quote">
“
<span class="quote">
return
</span>
”
</span>
an error.
<a class="link" href="signal.html" title="15.6.7.5 SIGNAL Statement">
<code class="literal">
SIGNAL
</code>
</a>
provides error information
to a handler, to an outer portion of the application, or to the
client. Also, it provides control over the error's
characteristics (error number,
<code class="literal">
SQLSTATE
</code>
value, message). Without
<a class="link" href="signal.html" title="15.6.7.5 SIGNAL Statement">
<code class="literal">
SIGNAL
</code>
</a>
,
it is necessary to resort to workarounds such as deliberately
referring to a nonexistent table to cause a routine to return an
error.
</p>
<p>
No privileges are required to execute the
<a class="link" href="signal.html" title="15.6.7.5 SIGNAL Statement">
<code class="literal">
SIGNAL
</code>
</a>
statement.
</p>
<p>
To retrieve information from the diagnostics area, use the
<a class="link" href="get-diagnostics.html" title="15.6.7.3 GET DIAGNOSTICS Statement">
<code class="literal">
GET DIAGNOSTICS
</code>
</a>
statement (see
<a class="xref" href="get-diagnostics.html" title="15.6.7.3 GET DIAGNOSTICS Statement">
Section 15.6.7.3, “GET DIAGNOSTICS Statement”
</a>
). For information about the
diagnostics area, see
<a class="xref" href="diagnostics-area.html" title="15.6.7.7 The MySQL Diagnostics Area">
Section 15.6.7.7, “The MySQL Diagnostics Area”
</a>
.
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<a class="xref" href="signal.html#signal-overview" title="SIGNAL Overview">
SIGNAL Overview
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="xref" href="signal.html#signal-condition-information-items" title="Signal Condition Information Items">
Signal Condition Information Items
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="xref" href="signal.html#signal-effects" title="Effect of Signals on Handlers, Cursors, and Statements">
Effect of Signals on Handlers, Cursors, and Statements
</a>
</p>
</li>
</ul>
</div>
<div class="simplesect">
<div class="titlepage">
<div>
<div class="simple">
<h5 class="title">
<a name="signal-overview">
</a>
SIGNAL Overview
</h5>
</div>
</div>
</div>
<p>
The
<em class="replaceable">
<code>
condition_value
</code>
</em>
in a
<a class="link" href="signal.html" title="15.6.7.5 SIGNAL Statement">
<code class="literal">
SIGNAL
</code>
</a>
statement indicates the
error value to be returned. It can be an
<code class="literal">
SQLSTATE
</code>
value (a 5-character string
literal) or a
<em class="replaceable">
<code>
condition_name
</code>
</em>
that
refers to a named condition previously defined with
<a class="link" href="declare-condition.html" title="15.6.7.1 DECLARE ... CONDITION Statement">
<code class="literal">
DECLARE ...
CONDITION
</code>
</a>
(see
<a class="xref" href="declare-condition.html" title="15.6.7.1 DECLARE ... CONDITION Statement">
Section 15.6.7.1, “DECLARE ... CONDITION Statement”
</a>
).
</p>
<p>
An
<code class="literal">
SQLSTATE
</code>
value can indicate errors,
warnings, or
<span class="quote">
“
<span class="quote">
not found.
</span>
”
</span>
The first two
characters of the value indicate its error class, as discussed
in
<a class="xref" href="signal.html#signal-condition-information-items" title="Signal Condition Information Items">
Signal Condition Information Items
</a>
. Some
signal values cause statement termination; see
<a class="xref" href="signal.html#signal-effects" title="Effect of Signals on Handlers, Cursors, and Statements">
Effect of Signals on Handlers, Cursors, and Statements
</a>
.
</p>
<p>
The
<code class="literal">
SQLSTATE
</code>
value for a
<a class="link" href="signal.html" title="15.6.7.5 SIGNAL Statement">
<code class="literal">
SIGNAL
</code>
</a>
statement should not
start with
<code class="literal">
'00'
</code>
because such values
indicate success and are not valid for signaling an error.
This is true whether the
<code class="literal">
SQLSTATE
</code>
value is
specified directly in the
<a class="link" href="signal.html" title="15.6.7.5 SIGNAL Statement">
<code class="literal">
SIGNAL
</code>
</a>
statement or in a named
condition referred to in the statement. If the value is
invalid, a
<code class="literal">
Bad SQLSTATE
</code>
error occurs.
</p>
<p>
To signal a generic
<code class="literal">
SQLSTATE
</code>
value, use
<code class="literal">
'45000'
</code>
, which means
<span class="quote">
“
<span class="quote">
unhandled
user-defined exception.
</span>
”
</span>
</p>
<p>
The
<a class="link" href="signal.html" title="15.6.7.5 SIGNAL Statement">
<code class="literal">
SIGNAL
</code>
</a>
statement optionally
includes a
<code class="literal">
SET
</code>
clause that contains
multiple signal items, in a list of
<em class="replaceable">
<code>
condition_information_item_name
</code>
</em>
=
<em class="replaceable">
<code>
simple_value_specification
</code>
</em>
assignments, separated by commas.
</p>
<p>
Each
<em class="replaceable">
<code>
condition_information_item_name
</code>
</em>
may
be specified only once in the
<code class="literal">
SET
</code>
clause.
Otherwise, a
<code class="literal">
Duplicate condition information
item
</code>
error occurs.
</p>
<p>
Valid
<em class="replaceable">
<code>
simple_value_specification
</code>
</em>
designators can be specified using stored procedure or
function parameters, stored program local variables declared
with
<a class="link" href="declare.html" title="15.6.3 DECLARE Statement">
<code class="literal">
DECLARE
</code>
</a>
, user-defined
variables, system variables, or literals. A character literal
may include a
<em class="replaceable">
<code>
_charset
</code>
</em>
introducer.
</p>
<p>
For information about permissible
<em class="replaceable">
<code>
condition_information_item_name
</code>
</em>
values, see
<a class="xref" href="signal.html#signal-condition-information-items" title="Signal Condition Information Items">
Signal Condition Information Items
</a>
.
</p>
<p>
The following procedure signals an error or warning depending
on the value of
<code class="literal">
pval
</code>
, its input parameter:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa7279585"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">CREATE</span> <span class="token keyword">PROCEDURE</span> p <span class="token punctuation">(</span>pval <span class="token datatype">INT</span><span class="token punctuation">)</span>
<span class="token keyword">BEGIN</span>
<span class="token keyword">DECLARE</span> specialty <span class="token keyword">CONDITION</span> <span class="token keyword">FOR</span> <span class="token keyword">SQLSTATE</span> <span class="token string">'45000'</span><span class="token punctuation">;</span>
<span class="token keyword">IF</span> pval <span class="token operator">=</span> <span class="token number">0</span> <span class="token keyword">THEN</span>
<span class="token keyword">SIGNAL</span> <span class="token keyword">SQLSTATE</span> <span class="token string">'01000'</span><span class="token punctuation">;</span>
<span class="token keyword">ELSEIF</span> pval <span class="token operator">=</span> <span class="token number">1</span> <span class="token keyword">THEN</span>
<span class="token keyword">SIGNAL</span> <span class="token keyword">SQLSTATE</span> <span class="token string">'45000'</span>
<span class="token keyword">SET</span> <span class="token keyword">MESSAGE_TEXT</span> <span class="token operator">=</span> <span class="token string">'An error occurred'</span><span class="token punctuation">;</span>
<span class="token keyword">ELSEIF</span> pval <span class="token operator">=</span> <span class="token number">2</span> <span class="token keyword">THEN</span>
<span class="token keyword">SIGNAL</span> specialty
<span class="token keyword">SET</span> <span class="token keyword">MESSAGE_TEXT</span> <span class="token operator">=</span> <span class="token string">'An error occurred'</span><span class="token punctuation">;</span>
<span class="token keyword">ELSE</span>
<span class="token keyword">SIGNAL</span> <span class="token keyword">SQLSTATE</span> <span class="token string">'01000'</span>
<span class="token keyword">SET</span> <span class="token keyword">MESSAGE_TEXT</span> <span class="token operator">=</span> <span class="token string">'A warning occurred'</span><span class="token punctuation">,</span> <span class="token keyword">MYSQL_ERRNO</span> <span class="token operator">=</span> <span class="token number">1000</span><span class="token punctuation">;</span>
<span class="token keyword">SIGNAL</span> <span class="token keyword">SQLSTATE</span> <span class="token string">'45000'</span>
<span class="token keyword">SET</span> <span class="token keyword">MESSAGE_TEXT</span> <span class="token operator">=</span> <span class="token string">'An error occurred'</span><span class="token punctuation">,</span> <span class="token keyword">MYSQL_ERRNO</span> <span class="token operator">=</span> <span class="token number">1001</span><span class="token punctuation">;</span>
<span class="token keyword">END</span> <span class="token keyword">IF</span><span class="token punctuation">;</span>
<span class="token keyword">END</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
If
<code class="literal">
pval
</code>
is 0,
<code class="literal">
p()
</code>
signals a warning because
<code class="literal">
SQLSTATE
</code>
values
that begin with
<code class="literal">
'01'
</code>
are signals in the
warning class. The warning does not terminate the procedure,
and can be seen with
<a class="link" href="show-warnings.html" title="15.7.7.42 SHOW WARNINGS Statement">
<code class="literal">
SHOW
WARNINGS
</code>
</a>
after the procedure returns.
</p>
<p>
If
<code class="literal">
pval
</code>
is 1,
<code class="literal">
p()
</code>
signals an error and sets the
<code class="literal">
MESSAGE_TEXT
</code>
condition information item. The error terminates the
procedure, and the text is returned with the error
information.
</p>
<p>
If
<code class="literal">
pval
</code>
is 2, the same error is signaled,
although the
<code class="literal">
SQLSTATE
</code>
value is specified
using a named condition in this case.
</p>
<p>
If
<code class="literal">
pval
</code>
is anything else,
<code class="literal">
p()
</code>
first signals a warning and sets the
message text and error number condition information items.
This warning does not terminate the procedure, so execution
continues and
<code class="literal">
p()
</code>
then signals an error.
The error does terminate the procedure. The message text and
error number set by the warning are replaced by the values set
by the error, which are returned with the error information.
</p>
<p>
<a class="link" href="signal.html" title="15.6.7.5 SIGNAL Statement">
<code class="literal">
SIGNAL
</code>
</a>
is typically used within
stored programs, but it is a MySQL extension that it is
permitted outside handler context. For example, if you invoke
the
<a class="link" href="mysql.html" title="6.5.1 mysql — The MySQL Command-Line Client">
<span class="command">
<strong>
mysql
</strong>
</span>
</a>
client program, you can enter any
of these statements at the prompt:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa45363892"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">SIGNAL</span> <span class="token keyword">SQLSTATE</span> <span class="token string">'77777'</span><span class="token punctuation">;</span>
<span class="token keyword">CREATE</span> <span class="token keyword">TRIGGER</span> t_bi <span class="token keyword">BEFORE</span> <span class="token keyword">INSERT</span> <span class="token keyword">ON</span> t
<span class="token keyword">FOR</span> <span class="token keyword">EACH</span> <span class="token keyword">ROW</span> <span class="token keyword">SIGNAL</span> <span class="token keyword">SQLSTATE</span> <span class="token string">'77777'</span><span class="token punctuation">;</span>
<span class="token keyword">CREATE</span> <span class="token keyword">EVENT</span> e <span class="token keyword">ON</span> <span class="token keyword">SCHEDULE</span> <span class="token keyword">EVERY</span> <span class="token number">1</span> <span class="token keyword">SECOND</span>
<span class="token keyword">DO</span> <span class="token keyword">SIGNAL</span> <span class="token keyword">SQLSTATE</span> <span class="token string">'77777'</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
<a class="link" href="signal.html" title="15.6.7.5 SIGNAL Statement">
<code class="literal">
SIGNAL
</code>
</a>
executes according to
the following rules:
</p>
<p>
If the
<a class="link" href="signal.html" title="15.6.7.5 SIGNAL Statement">
<code class="literal">
SIGNAL
</code>
</a>
statement
indicates a particular
<code class="literal">
SQLSTATE
</code>
value, that
value is used to signal the condition specified. Example:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa69391285"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">CREATE</span> <span class="token keyword">PROCEDURE</span> p <span class="token punctuation">(</span>divisor <span class="token datatype">INT</span><span class="token punctuation">)</span>
<span class="token keyword">BEGIN</span>
<span class="token keyword">IF</span> divisor <span class="token operator">=</span> <span class="token number">0</span> <span class="token keyword">THEN</span>
<span class="token keyword">SIGNAL</span> <span class="token keyword">SQLSTATE</span> <span class="token string">'22012'</span><span class="token punctuation">;</span>
<span class="token keyword">END</span> <span class="token keyword">IF</span><span class="token punctuation">;</span>
<span class="token keyword">END</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
If the
<a class="link" href="signal.html" title="15.6.7.5 SIGNAL Statement">
<code class="literal">
SIGNAL
</code>
</a>
statement uses a
named condition, the condition must be declared in some scope
that applies to the
<a class="link" href="signal.html" title="15.6.7.5 SIGNAL Statement">
<code class="literal">
SIGNAL
</code>
</a>
statement, and must be defined using an
<code class="literal">
SQLSTATE
</code>
value, not a MySQL error number.
Example:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa61550705"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">CREATE</span> <span class="token keyword">PROCEDURE</span> p <span class="token punctuation">(</span>divisor <span class="token datatype">INT</span><span class="token punctuation">)</span>
<span class="token keyword">BEGIN</span>
<span class="token keyword">DECLARE</span> divide_by_zero <span class="token keyword">CONDITION</span> <span class="token keyword">FOR</span> <span class="token keyword">SQLSTATE</span> <span class="token string">'22012'</span><span class="token punctuation">;</span>
<span class="token keyword">IF</span> divisor <span class="token operator">=</span> <span class="token number">0</span> <span class="token keyword">THEN</span>
<span class="token keyword">SIGNAL</span> divide_by_zero<span class="token punctuation">;</span>
<span class="token keyword">END</span> <span class="token keyword">IF</span><span class="token punctuation">;</span>
<span class="token keyword">END</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
If the named condition does not exist in the scope of the
<a class="link" href="signal.html" title="15.6.7.5 SIGNAL Statement">
<code class="literal">
SIGNAL
</code>
</a>
statement, an
<code class="literal">
Undefined CONDITION
</code>
error occurs.
</p>
<p>
If
<a class="link" href="signal.html" title="15.6.7.5 SIGNAL Statement">
<code class="literal">
SIGNAL
</code>
</a>
refers to a named
condition that is defined with a MySQL error number rather
than an
<code class="literal">
SQLSTATE
</code>
value, a
<code class="literal">
SIGNAL/RESIGNAL can only use a CONDITION defined with
SQLSTATE
</code>
error occurs. The following statements
cause that error because the named condition is associated
with a MySQL error number:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa41350643"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">DECLARE</span> no_such_table <span class="token keyword">CONDITION</span> <span class="token keyword">FOR</span> <span class="token number">1051</span><span class="token punctuation">;</span>
<span class="token keyword">SIGNAL</span> no_such_table<span class="token punctuation">;</span></code></pre>
</div>
<p>
If a condition with a given name is declared multiple times in
different scopes, the declaration with the most local scope
applies. Consider the following procedure:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa36879047"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">CREATE</span> <span class="token keyword">PROCEDURE</span> p <span class="token punctuation">(</span>divisor <span class="token datatype">INT</span><span class="token punctuation">)</span>
<span class="token keyword">BEGIN</span>
<span class="token keyword">DECLARE</span> my_error <span class="token keyword">CONDITION</span> <span class="token keyword">FOR</span> <span class="token keyword">SQLSTATE</span> <span class="token string">'45000'</span><span class="token punctuation">;</span>
<span class="token keyword">IF</span> divisor <span class="token operator">=</span> <span class="token number">0</span> <span class="token keyword">THEN</span>
<span class="token keyword">BEGIN</span>
<span class="token keyword">DECLARE</span> my_error <span class="token keyword">CONDITION</span> <span class="token keyword">FOR</span> <span class="token keyword">SQLSTATE</span> <span class="token string">'22012'</span><span class="token punctuation">;</span>
<span class="token keyword">SIGNAL</span> my_error<span class="token punctuation">;</span>
<span class="token keyword">END</span><span class="token punctuation">;</span>
<span class="token keyword">END</span> <span class="token keyword">IF</span><span class="token punctuation">;</span>
<span class="token keyword">SIGNAL</span> my_error<span class="token punctuation">;</span>
<span class="token keyword">END</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
If
<code class="literal">
divisor
</code>
is 0, the first
<a class="link" href="signal.html" title="15.6.7.5 SIGNAL Statement">
<code class="literal">
SIGNAL
</code>
</a>
statement executes. The
innermost
<code class="literal">
my_error
</code>
condition declaration
applies, raising
<code class="literal">
SQLSTATE
</code>
<code class="literal">
'22012'
</code>
.
</p>
<p>
If
<code class="literal">
divisor
</code>
is not 0, the second
<a class="link" href="signal.html" title="15.6.7.5 SIGNAL Statement">
<code class="literal">
SIGNAL
</code>
</a>
statement executes. The
outermost
<code class="literal">
my_error
</code>
condition declaration
applies, raising
<code class="literal">
SQLSTATE
</code>
<code class="literal">
'45000'
</code>
.
</p>
<p>
For information about how the server chooses handlers when a
condition occurs, see
<a class="xref" href="handler-scope.html" title="15.6.7.6 Scope Rules for Handlers">
Section 15.6.7.6, “Scope Rules for Handlers”
</a>
.
</p>
<p>
Signals can be raised within exception handlers:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa74884565"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">CREATE</span> <span class="token keyword">PROCEDURE</span> p <span class="token punctuation">(</span><span class="token punctuation">)</span>
<span class="token keyword">BEGIN</span>
<span class="token keyword">DECLARE</span> <span class="token keyword">EXIT</span> <span class="token keyword">HANDLER</span> <span class="token keyword">FOR</span> <span class="token keyword">SQLEXCEPTION</span>
<span class="token keyword">BEGIN</span>
<span class="token keyword">SIGNAL</span> <span class="token keyword">SQLSTATE</span> <span class="token keyword">VALUE</span> <span class="token string">'99999'</span>
<span class="token keyword">SET</span> <span class="token keyword">MESSAGE_TEXT</span> <span class="token operator">=</span> <span class="token string">'An error occurred'</span><span class="token punctuation">;</span>
<span class="token keyword">END</span><span class="token punctuation">;</span>
<span class="token keyword">DROP</span> <span class="token keyword">TABLE</span> no_such_table<span class="token punctuation">;</span>
<span class="token keyword">END</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
<code class="literal">
CALL p()
</code>
reaches the
<a class="link" href="drop-table.html" title="15.1.32 DROP TABLE Statement">
<code class="literal">
DROP TABLE
</code>
</a>
statement. There is
no table named
<code class="literal">
no_such_table
</code>
, so the error
handler is activated. The error handler destroys the original
error (
<span class="quote">
“
<span class="quote">
no such table
</span>
”
</span>
) and makes a new error
with
<code class="literal">
SQLSTATE
</code>
<code class="literal">
'99999'
</code>
and message
<code class="literal">
An error occurred
</code>
.
</p>
</div>
<div class="simplesect">
<div class="titlepage">
<div>
<div class="simple">
<h5 class="title">
<a name="signal-condition-information-items">
</a>
Signal Condition Information Items
</h5>
</div>
</div>
</div>
<p>
The following table lists the names of diagnostics area
condition information items that can be set in a
<a class="link" href="signal.html" title="15.6.7.5 SIGNAL Statement">
<code class="literal">
SIGNAL
</code>
</a>
(or
<a class="link" href="resignal.html" title="15.6.7.4 RESIGNAL Statement">
<code class="literal">
RESIGNAL
</code>
</a>
) statement. All items
are standard SQL except
<code class="literal">
MYSQL_ERRNO
</code>
, which
is a MySQL extension. For more information about these items
see
<a class="xref" href="diagnostics-area.html" title="15.6.7.7 The MySQL Diagnostics Area">
Section 15.6.7.7, “The MySQL Diagnostics Area”
</a>
.
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-none"><div class="docs-select-all right" id="sa73481612"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-none">Item Name Definition
--------- ----------
CLASS_ORIGIN VARCHAR(64)
SUBCLASS_ORIGIN VARCHAR(64)
CONSTRAINT_CATALOG VARCHAR(64)
CONSTRAINT_SCHEMA VARCHAR(64)
CONSTRAINT_NAME VARCHAR(64)
CATALOG_NAME VARCHAR(64)
SCHEMA_NAME VARCHAR(64)
TABLE_NAME VARCHAR(64)
COLUMN_NAME VARCHAR(64)
CURSOR_NAME VARCHAR(64)
MESSAGE_TEXT VARCHAR(128)
MYSQL_ERRNO SMALLINT UNSIGNED</code></pre>
</div>
<p>
The character set for character items is UTF-8.
</p>
<p>
It is illegal to assign
<code class="literal">
NULL
</code>
to a condition
information item in a
<a class="link" href="signal.html" title="15.6.7.5 SIGNAL Statement">
<code class="literal">
SIGNAL
</code>
</a>
statement.
</p>
<p>
A
<a class="link" href="signal.html" title="15.6.7.5 SIGNAL Statement">
<code class="literal">
SIGNAL
</code>
</a>
statement always
specifies an
<code class="literal">
SQLSTATE
</code>
value, either
directly, or indirectly by referring to a named condition
defined with an
<code class="literal">
SQLSTATE
</code>
value. The first
two characters of an
<code class="literal">
SQLSTATE
</code>
value are its
class, and the class determines the default value for the
condition information items:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
Class =
<code class="literal">
'00'
</code>
(success)
</p>
<p>
Illegal.
<code class="literal">
SQLSTATE
</code>
values that begin
with
<code class="literal">
'00'
</code>
indicate success and are not
valid for
<a class="link" href="signal.html" title="15.6.7.5 SIGNAL Statement">
<code class="literal">
SIGNAL
</code>
</a>
.
</p>
</li>
<li class="listitem">
<p>
Class =
<code class="literal">
'01'
</code>
(warning)
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa14701011"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">MESSAGE_TEXT</span> <span class="token operator">=</span> <span class="token string">'Unhandled user-defined warning condition'</span><span class="token punctuation">;</span>
<span class="token keyword">MYSQL_ERRNO</span> <span class="token operator">=</span> ER_SIGNAL_WARN</code></pre>
</div>
</li>
<li class="listitem">
<p>
Class =
<code class="literal">
'02'
</code>
(not found)
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa93113130"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">MESSAGE_TEXT</span> <span class="token operator">=</span> <span class="token string">'Unhandled user-defined not found condition'</span><span class="token punctuation">;</span>
<span class="token keyword">MYSQL_ERRNO</span> <span class="token operator">=</span> ER_SIGNAL_NOT_FOUND</code></pre>
</div>
</li>
<li class="listitem">
<p>
Class >
<code class="literal">
'02'
</code>
(exception)
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa24968433"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">MESSAGE_TEXT</span> <span class="token operator">=</span> <span class="token string">'Unhandled user-defined exception condition'</span><span class="token punctuation">;</span>
<span class="token keyword">MYSQL_ERRNO</span> <span class="token operator">=</span> ER_SIGNAL_EXCEPTION</code></pre>
</div>
</li>
</ul>
</div>
<p>
For legal classes, the other condition information items are
set as follows:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa74721402"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">CLASS_ORIGIN</span> <span class="token operator">=</span> <span class="token keyword">SUBCLASS_ORIGIN</span> <span class="token operator">=</span> <span class="token string">''</span><span class="token punctuation">;</span>
<span class="token keyword">CONSTRAINT_CATALOG</span> <span class="token operator">=</span> <span class="token keyword">CONSTRAINT_SCHEMA</span> <span class="token operator">=</span> <span class="token keyword">CONSTRAINT_NAME</span> <span class="token operator">=</span> <span class="token string">''</span><span class="token punctuation">;</span>
<span class="token keyword">CATALOG_NAME</span> <span class="token operator">=</span> <span class="token keyword">SCHEMA_NAME</span> <span class="token operator">=</span> <span class="token keyword">TABLE_NAME</span> <span class="token operator">=</span> <span class="token keyword">COLUMN_NAME</span> <span class="token operator">=</span> <span class="token string">''</span><span class="token punctuation">;</span>
<span class="token keyword">CURSOR_NAME</span> <span class="token operator">=</span> <span class="token string">''</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
The error values that are accessible after
<a class="link" href="signal.html" title="15.6.7.5 SIGNAL Statement">
<code class="literal">
SIGNAL
</code>
</a>
executes are the
<code class="literal">
SQLSTATE
</code>
value raised by the
<a class="link" href="signal.html" title="15.6.7.5 SIGNAL Statement">
<code class="literal">
SIGNAL
</code>
</a>
statement and the
<code class="literal">
MESSAGE_TEXT
</code>
and
<code class="literal">
MYSQL_ERRNO
</code>
items. These values are
available from the C API:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<a class="ulink" href="/doc/c-api/8.4/en/mysql-sqlstate.html" target="_top">
<code class="literal">
mysql_sqlstate()
</code>
</a>
returns
the
<code class="literal">
SQLSTATE
</code>
value.
</p>
</li>
<li class="listitem">
<p>
<a class="ulink" href="/doc/c-api/8.4/en/mysql-errno.html" target="_top">
<code class="literal">
mysql_errno()
</code>
</a>
returns the
<code class="literal">
MYSQL_ERRNO
</code>
value.
</p>
</li>
<li class="listitem">
<p>
<a class="ulink" href="/doc/c-api/8.4/en/mysql-error.html" target="_top">
<code class="literal">
mysql_error()
</code>
</a>
returns the
<code class="literal">
MESSAGE_TEXT
</code>
value.
</p>
</li>
</ul>
</div>
<p>
At the SQL level, the output from
<a class="link" href="show-warnings.html" title="15.7.7.42 SHOW WARNINGS Statement">
<code class="literal">
SHOW
WARNINGS
</code>
</a>
and
<a class="link" href="show-errors.html" title="15.7.7.18 SHOW ERRORS Statement">
<code class="literal">
SHOW
ERRORS
</code>
</a>
indicates the
<code class="literal">
MYSQL_ERRNO
</code>
and
<code class="literal">
MESSAGE_TEXT
</code>
values in the
<code class="literal">
Code
</code>
and
<code class="literal">
Message
</code>
columns.
</p>
<p>
To retrieve information from the diagnostics area, use the
<a class="link" href="get-diagnostics.html" title="15.6.7.3 GET DIAGNOSTICS Statement">
<code class="literal">
GET DIAGNOSTICS
</code>
</a>
statement (see
<a class="xref" href="get-diagnostics.html" title="15.6.7.3 GET DIAGNOSTICS Statement">
Section 15.6.7.3, “GET DIAGNOSTICS Statement”
</a>
). For information about the
diagnostics area, see
<a class="xref" href="diagnostics-area.html" title="15.6.7.7 The MySQL Diagnostics Area">
Section 15.6.7.7, “The MySQL Diagnostics Area”
</a>
.
</p>
</div>
<div class="simplesect">
<div class="titlepage">
<div>
<div class="simple">
<h5 class="title">
<a name="signal-effects">
</a>
Effect of Signals on Handlers, Cursors, and Statements
</h5>
</div>
</div>
</div>
<p>
Signals have different effects on statement execution
depending on the signal class. The class determines how severe
an error is. MySQL ignores the value of the
<a class="link" href="server-system-variables.html#sysvar_sql_mode">
<code class="literal">
sql_mode
</code>
</a>
system variable; in
particular, strict SQL mode does not matter. MySQL also
ignores
<code class="literal">
IGNORE
</code>
: The intent of
<a class="link" href="signal.html" title="15.6.7.5 SIGNAL Statement">
<code class="literal">
SIGNAL
</code>
</a>
is to raise a
user-generated error explicitly, so a signal is never ignored.
</p>
<p>
In the following descriptions,
<span class="quote">
“
<span class="quote">
unhandled
</span>
”
</span>
means
that no handler for the signaled
<code class="literal">
SQLSTATE
</code>
value has been defined with
<a class="link" href="declare-handler.html" title="15.6.7.2 DECLARE ... HANDLER Statement">
<code class="literal">
DECLARE ...
HANDLER
</code>
</a>
.
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
Class =
<code class="literal">
'00'
</code>
(success)
</p>
<p>
Illegal.
<code class="literal">
SQLSTATE
</code>
values that begin
with
<code class="literal">
'00'
</code>
indicate success and are not
valid for
<a class="link" href="signal.html" title="15.6.7.5 SIGNAL Statement">
<code class="literal">
SIGNAL
</code>
</a>
.
</p>
</li>
<li class="listitem">
<p>
Class =
<code class="literal">
'01'
</code>
(warning)
</p>
<p>
The value of the
<a class="link" href="server-system-variables.html#sysvar_warning_count">
<code class="literal">
warning_count
</code>
</a>
system
variable goes up.
<a class="link" href="show-warnings.html" title="15.7.7.42 SHOW WARNINGS Statement">
<code class="literal">
SHOW
WARNINGS
</code>
</a>
shows the signal.
<code class="literal">
SQLWARNING
</code>
handlers catch the signal.
</p>
<p>
Warnings cannot be returned from stored functions because
the
<a class="link" href="return.html" title="15.6.5.7 RETURN Statement">
<code class="literal">
RETURN
</code>
</a>
statement that
causes the function to return clears the diagnostic area.
The statement thus clears any warnings that may have been
present there (and resets
<a class="link" href="server-system-variables.html#sysvar_warning_count">
<code class="literal">
warning_count
</code>
</a>
to 0).
</p>
</li>
<li class="listitem">
<p>
Class =
<code class="literal">
'02'
</code>
(not found)
</p>
<p>
<code class="literal">
NOT FOUND
</code>
handlers catch the signal.
There is no effect on cursors. If the signal is unhandled
in a stored function, statements end.
</p>
</li>
<li class="listitem">
<p>
Class >
<code class="literal">
'02'
</code>
(exception)
</p>
<p>
<code class="literal">
SQLEXCEPTION
</code>
handlers catch the signal.
If the signal is unhandled in a stored function,
statements end.
</p>
</li>
<li class="listitem">
<p>
Class =
<code class="literal">
'40'
</code>
</p>
<p>
Treated as an ordinary exception.
</p>
</li>
</ul>
</div>
</div>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/outer-join-optimization.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="outer-join-optimization">
</a>
10.2.1.9 Outer Join Optimization
</h4>
</div>
</div>
</div>
<a class="indexterm" name="idm46045229445232">
</a>
<a class="indexterm" name="idm46045229443744">
</a>
<a class="indexterm" name="idm46045229442256">
</a>
<a class="indexterm" name="idm46045229441184">
</a>
<a class="indexterm" name="idm46045229439696">
</a>
<a class="indexterm" name="idm46045229438624">
</a>
<p>
Outer joins include
<code class="literal">
LEFT JOIN
</code>
and
<code class="literal">
RIGHT JOIN
</code>
.
</p>
<p>
MySQL implements an
<code class="literal">
<em class="replaceable">
<code>
A
</code>
</em>
LEFT
JOIN
<em class="replaceable">
<code>
B
</code>
</em>
<em class="replaceable">
<code>
join_specification
</code>
</em>
</code>
as
follows:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
Table
<em class="replaceable">
<code>
B
</code>
</em>
is set to depend on
table
<em class="replaceable">
<code>
A
</code>
</em>
and all tables on which
<em class="replaceable">
<code>
A
</code>
</em>
depends.
</p>
</li>
<li class="listitem">
<p>
Table
<em class="replaceable">
<code>
A
</code>
</em>
is set to depend on all
tables (except
<em class="replaceable">
<code>
B
</code>
</em>
) that are used
in the
<code class="literal">
LEFT JOIN
</code>
condition.
</p>
</li>
<li class="listitem">
<p>
The
<code class="literal">
LEFT JOIN
</code>
condition is used to
decide how to retrieve rows from table
<em class="replaceable">
<code>
B
</code>
</em>
. (In other words, any
condition in the
<code class="literal">
WHERE
</code>
clause is not
used.)
</p>
</li>
<li class="listitem">
<p>
All standard join optimizations are performed, with the
exception that a table is always read after all tables on
which it depends. If there is a circular dependency, an
error occurs.
</p>
</li>
<li class="listitem">
<p>
All standard
<code class="literal">
WHERE
</code>
optimizations are
performed.
</p>
</li>
<li class="listitem">
<p>
If there is a row in
<em class="replaceable">
<code>
A
</code>
</em>
that
matches the
<code class="literal">
WHERE
</code>
clause, but there is
no row in
<em class="replaceable">
<code>
B
</code>
</em>
that matches the
<code class="literal">
ON
</code>
condition, an extra
<em class="replaceable">
<code>
B
</code>
</em>
row is generated with all
columns set to
<code class="literal">
NULL
</code>
.
</p>
</li>
<li class="listitem">
<p>
If you use
<code class="literal">
LEFT JOIN
</code>
to find rows that
do not exist in some table and you have the following
test:
<code class="literal">
<em class="replaceable">
<code>
col_name
</code>
</em>
IS
NULL
</code>
in the
<code class="literal">
WHERE
</code>
part, where
<em class="replaceable">
<code>
col_name
</code>
</em>
is a column that is
declared as
<code class="literal">
NOT NULL
</code>
, MySQL stops
searching for more rows (for a particular key combination)
after it has found one row that matches the
<code class="literal">
LEFT
JOIN
</code>
condition.
</p>
</li>
</ul>
</div>
<p>
The
<code class="literal">
RIGHT JOIN
</code>
implementation is analogous
to that of
<code class="literal">
LEFT JOIN
</code>
with the table roles
reversed. Right joins are converted to equivalent left joins,
as described in
<a class="xref" href="outer-join-simplification.html" title="10.2.1.10 Outer Join Simplification">
Section 10.2.1.10, “Outer Join Simplification”
</a>
.
</p>
<p>
For a
<code class="literal">
LEFT JOIN
</code>
, if the
<code class="literal">
WHERE
</code>
condition is always false for the
generated
<code class="literal">
NULL
</code>
row, the
<code class="literal">
LEFT
JOIN
</code>
is changed to an inner join. For example, the
<code class="literal">
WHERE
</code>
clause would be false in the
following query if
<code class="literal">
t2.column1
</code>
were
<code class="literal">
NULL
</code>
:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-sql"><div class="docs-select-all right" id="sa15174580"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">SELECT</span> <span class="token operator">*</span> <span class="token keyword">FROM</span> t1 <span class="token keyword">LEFT</span> <span class="token keyword">JOIN</span> t2 <span class="token keyword">ON</span> <span class="token punctuation">(</span>column1<span class="token punctuation">)</span> <span class="token keyword">WHERE</span> t2<span class="token punctuation">.</span>column2<span class="token operator">=</span><span class="token number">5</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
Therefore, it is safe to convert the query to an inner join:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-sql"><div class="docs-select-all right" id="sa38754113"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">SELECT</span> <span class="token operator">*</span> <span class="token keyword">FROM</span> t1<span class="token punctuation">,</span> t2 <span class="token keyword">WHERE</span> t2<span class="token punctuation">.</span>column2<span class="token operator">=</span><span class="token number">5</span> <span class="token operator">AND</span> t1<span class="token punctuation">.</span>column1<span class="token operator">=</span>t2<span class="token punctuation">.</span>column1<span class="token punctuation">;</span></code></pre>
</div>
<p>
Trivial
<code class="literal">
WHERE
</code>
conditions arising from
constant literal expressions are removed during preparation,
rather than at a later stage in optimization, by which time
joins have already been simplified. Earlier removal of trivial
conditions allows the optimizer to convert outer joins to
inner joins; this can result in improved plans for queries
with outer joins containing trivial conditions in the
<code class="literal">
WHERE
</code>
clause, such as this one:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-sql"><div class="docs-select-all right" id="sa31063617"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">SELECT</span> <span class="token operator">*</span> <span class="token keyword">FROM</span> t1 <span class="token keyword">LEFT</span> <span class="token keyword">JOIN</span> t2 <span class="token keyword">ON</span> <em class="replaceable">condition_1</em> <span class="token keyword">WHERE</span> <em class="replaceable">condition_2</em> <span class="token operator">OR</span> <span class="token number">0</span> <span class="token operator">=</span> <span class="token number">1</span></code></pre>
</div>
<p>
The optimizer now sees during preparation that 0 = 1 is always
false, making
<code class="literal">
OR 0 = 1
</code>
redundant, and
removes it, leaving this:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-sql"><div class="docs-select-all right" id="sa88002847"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">SELECT</span> <span class="token operator">*</span> <span class="token keyword">FROM</span> t1 <span class="token keyword">LEFT</span> <span class="token keyword">JOIN</span> t2 <span class="token keyword">ON</span> <em class="replaceable">condition_1</em> <span class="token keyword">where</span> <em class="replaceable">condition_2</em></code></pre>
</div>
<p>
Now the optimizer can rewrite the query as an inner join, like
this:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-sql"><div class="docs-select-all right" id="sa80784111"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">SELECT</span> <span class="token operator">*</span> <span class="token keyword">FROM</span> t1 <span class="token keyword">JOIN</span> t2 <span class="token keyword">WHERE</span> <em class="replaceable">condition_1</em> <span class="token operator">AND</span> <em class="replaceable">condition_2</em></code></pre>
</div>
<a class="indexterm" name="idm46045229392944">
</a>
<p>
Now the optimizer can use table
<code class="literal">
t2
</code>
before
table
<code class="literal">
t1
</code>
if doing so would result in a
better query plan. To provide a hint about the table join
order, use optimizer hints; see
<a class="xref" href="optimizer-hints.html" title="10.9.3 Optimizer Hints">
Section 10.9.3, “Optimizer Hints”
</a>
. Alternatively, use
<code class="literal">
STRAIGHT_JOIN
</code>
; see
<a class="xref" href="select.html" title="15.2.13 SELECT Statement">
Section 15.2.13, “SELECT Statement”
</a>
. However,
<code class="literal">
STRAIGHT_JOIN
</code>
may prevent indexes from
being used because it disables semijoin transformations; see
<a class="ulink" href="/doc/refman/8.0/en/semijoins.html" target="_top">
Optimizing IN and EXISTS Subquery Predicates with Semijoin Transformations
</a>
.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/replication-solutions-backups.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="replication-solutions-backups">
</a>
19.4.1 Using Replication for Backups
</h3>
</div>
</div>
</div>
<div class="toc">
<dl class="toc">
<dt>
<span class="section">
<a href="replication-solutions-backups-mysqldump.html">
19.4.1.1 Backing Up a Replica Using mysqldump
</a>
</span>
</dt>
<dt>
<span class="section">
<a href="replication-solutions-backups-rawdata.html">
19.4.1.2 Backing Up Raw Data from a Replica
</a>
</span>
</dt>
<dt>
<span class="section">
<a href="replication-solutions-backups-read-only.html">
19.4.1.3 Backing Up a Source or Replica by Making It Read Only
</a>
</span>
</dt>
</dl>
</div>
<p>
To use replication as a backup solution, replicate data from the
source to a replica, and then back up the replica. The replica can
be paused and shut down without affecting the running operation of
the source, so you can produce an effective snapshot of
<span class="quote">
“
<span class="quote">
live
</span>
”
</span>
data that would otherwise require the source
to be shut down.
</p>
<p>
How you back up a database depends on its size and whether you are
backing up only the data, or the data and the replica state so
that you can rebuild the replica in the event of failure. There
are therefore two choices:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
If you are using replication as a solution to enable you to
back up the data on the source, and the size of your database
is not too large, the
<a class="link" href="mysqldump.html" title="6.5.4 mysqldump — A Database Backup Program">
<span class="command">
<strong>
mysqldump
</strong>
</span>
</a>
tool may be
suitable. See
<a class="xref" href="replication-solutions-backups-mysqldump.html" title="19.4.1.1 Backing Up a Replica Using mysqldump">
Section 19.4.1.1, “Backing Up a Replica Using mysqldump”
</a>
.
</p>
</li>
<li class="listitem">
<p>
For larger databases, where
<a class="link" href="mysqldump.html" title="6.5.4 mysqldump — A Database Backup Program">
<span class="command">
<strong>
mysqldump
</strong>
</span>
</a>
would
be impractical or inefficient, you can back up the raw data
files instead. Using the raw data files option also means that
you can back up the binary and relay logs that make it
possible to re-create the replica in the event of a replica
failure. For more information, see
<a class="xref" href="replication-solutions-backups-rawdata.html" title="19.4.1.2 Backing Up Raw Data from a Replica">
Section 19.4.1.2, “Backing Up Raw Data from a Replica”
</a>
.
</p>
</li>
</ul>
</div>
<p>
Another backup strategy, which can be used for either source or
replica servers, is to put the server in a read-only state. The
backup is performed against the read-only server, which then is
changed back to its usual read/write operational status. See
<a class="xref" href="replication-solutions-backups-read-only.html" title="19.4.1.3 Backing Up a Source or Replica by Making It Read Only">
Section 19.4.1.3, “Backing Up a Source or Replica by Making It Read Only”
</a>
.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/account-activity-auditing.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="account-activity-auditing">
</a>
8.2.23 SQL-Based Account Activity Auditing
</h3>
</div>
</div>
</div>
<p>
Applications can use the following guidelines to perform SQL-based
auditing that ties database activity to MySQL accounts.
</p>
<p>
MySQL accounts correspond to rows in the
<code class="literal">
mysql.user
</code>
system table. When a client connects
successfully, the server authenticates the client to a particular
row in this table. The
<code class="literal">
User
</code>
and
<code class="literal">
Host
</code>
column values in this row uniquely
identify the account and correspond to the
<code class="literal">
'
<em class="replaceable">
<code>
user_name
</code>
</em>
'@'
<em class="replaceable">
<code>
host_name
</code>
</em>
'
</code>
format in which account names are written in SQL statements.
</p>
<p>
The account used to authenticate a client determines which
privileges the client has. Normally, the
<a class="link" href="information-functions.html#function_current-user">
<code class="literal">
CURRENT_USER()
</code>
</a>
function can be
invoked to determine which account this is for the client user.
Its value is constructed from the
<code class="literal">
User
</code>
and
<code class="literal">
Host
</code>
columns of the
<code class="literal">
user
</code>
table row for the account.
</p>
<p>
However, there are circumstances under which the
<a class="link" href="information-functions.html#function_current-user">
<code class="literal">
CURRENT_USER()
</code>
</a>
value corresponds
not to the client user but to a different account. This occurs in
contexts when privilege checking is not based the client's
account:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
Stored routines (procedures and functions) defined with the
<code class="literal">
SQL SECURITY DEFINER
</code>
characteristic
</p>
</li>
<li class="listitem">
<p>
Views defined with the
<code class="literal">
SQL SECURITY DEFINER
</code>
characteristic
</p>
</li>
<li class="listitem">
<p>
Triggers and events
</p>
</li>
</ul>
</div>
<p>
In those contexts, privilege checking is done against the
<code class="literal">
DEFINER
</code>
account and
<a class="link" href="information-functions.html#function_current-user">
<code class="literal">
CURRENT_USER()
</code>
</a>
refers to that
account, not to the account for the client who invoked the stored
routine or view or who caused the trigger to activate. To
determine the invoking user, you can call the
<a class="link" href="information-functions.html#function_user">
<code class="literal">
USER()
</code>
</a>
function, which returns a
value indicating the actual user name provided by the client and
the host from which the client connected. However, this value does
not necessarily correspond directly to an account in the
<code class="literal">
user
</code>
table, because the
<a class="link" href="information-functions.html#function_user">
<code class="literal">
USER()
</code>
</a>
value never contains
wildcards, whereas account values (as returned by
<a class="link" href="information-functions.html#function_current-user">
<code class="literal">
CURRENT_USER()
</code>
</a>
) may contain user
name and host name wildcards.
</p>
<p>
For example, a blank user name matches any user, so an account of
<code class="literal">
''@'localhost'
</code>
enables clients to connect as an
anonymous user from the local host with any user name. In this
case, if a client connects as
<code class="literal">
user1
</code>
from the
local host,
<a class="link" href="information-functions.html#function_user">
<code class="literal">
USER()
</code>
</a>
and
<a class="link" href="information-functions.html#function_current-user">
<code class="literal">
CURRENT_USER()
</code>
</a>
return different
values:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa75509038"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">USER</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">,</span> <span class="token function">CURRENT_USER</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> USER() <span class="token punctuation">|</span> CURRENT_USER() <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> user1@localhost <span class="token punctuation">|</span> @localhost <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span></code></pre>
</div>
<p>
The host name part of an account can also contain wildcards. If
the host name contains a
<code class="literal">
'%'
</code>
or
<code class="literal">
'_'
</code>
pattern character or uses netmask notation,
the account can be used for clients connecting from multiple hosts
and the
<a class="link" href="information-functions.html#function_current-user">
<code class="literal">
CURRENT_USER()
</code>
</a>
value does
not indicate which one. For example, the account
<code class="literal">
'user2'@'%.example.com'
</code>
can be used by
<code class="literal">
user2
</code>
to connect from any host in the
<code class="literal">
example.com
</code>
domain. If
<code class="literal">
user2
</code>
connects from
<code class="literal">
remote.example.com
</code>
,
<a class="link" href="information-functions.html#function_user">
<code class="literal">
USER()
</code>
</a>
and
<a class="link" href="information-functions.html#function_current-user">
<code class="literal">
CURRENT_USER()
</code>
</a>
return different
values:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa21735375"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">USER</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">,</span> <span class="token function">CURRENT_USER</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> USER() <span class="token punctuation">|</span> CURRENT_USER() <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> [email protected] <span class="token punctuation">|</span> user2@%.example.com <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span></code></pre>
</div>
<p>
If an application must invoke
<a class="link" href="information-functions.html#function_user">
<code class="literal">
USER()
</code>
</a>
for user auditing (for
example, if it does auditing from within triggers) but must also
be able to associate the
<a class="link" href="information-functions.html#function_user">
<code class="literal">
USER()
</code>
</a>
value with an account in the
<code class="literal">
user
</code>
table, it is
necessary to avoid accounts that contain wildcards in the
<code class="literal">
User
</code>
or
<code class="literal">
Host
</code>
column.
Specifically, do not permit
<code class="literal">
User
</code>
to be empty
(which creates an anonymous-user account), and do not permit
pattern characters or netmask notation in
<code class="literal">
Host
</code>
values. All accounts must have a nonempty
<code class="literal">
User
</code>
value and literal
<code class="literal">
Host
</code>
value.
</p>
<p>
With respect to the previous examples, the
<code class="literal">
''@'localhost'
</code>
and
<code class="literal">
'user2'@'%.example.com'
</code>
accounts should be
changed not to use wildcards:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa80687288"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">RENAME</span> <span class="token keyword">USER</span> <span class="token string">''</span>@<span class="token string">'localhost'</span> <span class="token keyword">TO</span> <span class="token string">'user1'</span>@<span class="token string">'localhost'</span><span class="token punctuation">;</span>
<span class="token keyword">RENAME</span> <span class="token keyword">USER</span> <span class="token string">'user2'</span>@<span class="token string">'%.example.com'</span> <span class="token keyword">TO</span> <span class="token string">'user2'</span>@<span class="token string">'remote.example.com'</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
If
<code class="literal">
user2
</code>
must be able to connect from several
hosts in the
<code class="literal">
example.com
</code>
domain, there should
be a separate account for each host.
</p>
<p>
To extract the user name or host name part from a
<a class="link" href="information-functions.html#function_current-user">
<code class="literal">
CURRENT_USER()
</code>
</a>
or
<a class="link" href="information-functions.html#function_user">
<code class="literal">
USER()
</code>
</a>
value, use the
<a class="link" href="string-functions.html#function_substring-index">
<code class="literal">
SUBSTRING_INDEX()
</code>
</a>
function:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa75959185"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">SUBSTRING_INDEX</span><span class="token punctuation">(</span><span class="token function">CURRENT_USER</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">,</span><span class="token string">'@'</span><span class="token punctuation">,</span><span class="token number">1</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> SUBSTRING_INDEX(CURRENT_USER(),'@',1) <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> user1 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">SUBSTRING_INDEX</span><span class="token punctuation">(</span><span class="token function">CURRENT_USER</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">,</span><span class="token string">'@'</span><span class="token punctuation">,</span><span class="token operator">-</span><span class="token number">1</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> SUBSTRING_INDEX(CURRENT_USER(),'@',<span class="token punctuation">-</span>1) <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> localhost <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span></code></pre>
</div>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-backup-parallel-data-nodes.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="mysql-cluster-backup-parallel-data-nodes">
</a>
25.6.8.5 Taking an NDB Backup with Parallel Data Nodes
</h4>
</div>
</div>
</div>
<p>
It is possible to take a backup with multiple local data
managers (LDMs) acting in parallel on the data nodes. For this
to work, all data nodes in the cluster must use multiple LDMs,
and each data node must use the same number of LDMs. This means
that all data nodes must run
<a class="link" href="mysql-cluster-programs-ndbmtd.html" title="25.5.3 ndbmtd — The NDB Cluster Data Node Daemon (Multi-Threaded)">
<span class="command">
<strong>
ndbmtd
</strong>
</span>
</a>
(
<a class="link" href="mysql-cluster-programs-ndbd.html" title="25.5.1 ndbd — The NDB Cluster Data Node Daemon">
<span class="command">
<strong>
ndbd
</strong>
</span>
</a>
is single-threaded and thus always has
only one LDM) and they must be configured to use multiple LDMs
before taking the backup;
<a class="link" href="mysql-cluster-programs-ndbmtd.html" title="25.5.3 ndbmtd — The NDB Cluster Data Node Daemon (Multi-Threaded)">
<span class="command">
<strong>
ndbmtd
</strong>
</span>
</a>
by default
runs in single-threaded mode. You can cause them to use multiple
LDMs by choosing an appropriate setting for one of the
multi-threaded data node configuration parameters
<a class="link" href="mysql-cluster-ndbd-definition.html#ndbparam-ndbmtd-maxnoofexecutionthreads">
<code class="literal">
MaxNoOfExecutionThreads
</code>
</a>
or
<a class="link" href="mysql-cluster-ndbd-definition.html#ndbparam-ndbmtd-threadconfig">
<code class="literal">
ThreadConfig
</code>
</a>
. Keep
in mind that changing these parameters requires a restart of the
cluster; this can be a rolling restart. In addition, the
<a class="link" href="mysql-cluster-ndbd-definition.html#ndbparam-ndbmtd-enablemultithreadedbackup">
<code class="literal">
EnableMultithreadedBackup
</code>
</a>
parameter must be set to 1 for each data node (this is the
default).
</p>
<p>
Depending on the number of LDMs and other factors, you may also
need to increase
<a class="link" href="mysql-cluster-ndbd-definition.html#ndbparam-ndbmtd-nooffragmentlogparts">
<code class="literal">
NoOfFragmentLogParts
</code>
</a>
.
If you are using large Disk Data tables, you may also need to
increase
<a class="link" href="mysql-cluster-ndbd-definition.html#ndbparam-ndbd-diskpagebuffermemory">
<code class="literal">
DiskPageBufferMemory
</code>
</a>
. As
with single-threaded backups, you may also want or need to make
adjustments to settings for
<a class="link" href="mysql-cluster-ndbd-definition.html#ndbparam-ndbd-backupdatabuffersize">
<code class="literal">
BackupDataBufferSize
</code>
</a>
,
<a class="link" href="mysql-cluster-ndbd-definition.html#ndbparam-ndbd-backupmemory">
<code class="literal">
BackupMemory
</code>
</a>
, and other
configuration parameters relating to backups (see
<a class="xref" href="mysql-cluster-ndbd-definition.html#mysql-cluster-backup-parameters" title="Backup parameters">
Backup parameters
</a>
).
</p>
<p>
Once all data nodes are using multiple LDMs, you can take the
parallel backup using the
<a class="link" href="mysql-cluster-backup-using-management-client.html" title="25.6.8.2 Using The NDB Cluster Management Client to Create a Backup">
<code class="literal">
START
BACKUP
</code>
</a>
command in the NDB management client just as
you would if the data nodes were running
<a class="link" href="mysql-cluster-programs-ndbd.html" title="25.5.1 ndbd — The NDB Cluster Data Node Daemon">
<span class="command">
<strong>
ndbd
</strong>
</span>
</a>
(or
<a class="link" href="mysql-cluster-programs-ndbmtd.html" title="25.5.3 ndbmtd — The NDB Cluster Data Node Daemon (Multi-Threaded)">
<span class="command">
<strong>
ndbmtd
</strong>
</span>
</a>
in single-threaded mode); no
additional or special syntax is required, and you can specify a
backup ID, wait option, or snapshot option in any combination as
needed or desired.
</p>
<p>
Backups using multiple LDMs create subdirectories, one per LDM,
under the directory
<code class="filename">
BACKUP/BACKUP-
<em class="replaceable">
<code>
backup_id
</code>
</em>
/
</code>
(which in turn resides under the
<a class="link" href="mysql-cluster-ndbd-definition.html#ndbparam-ndbd-backupdatadir">
<code class="literal">
BackupDataDir
</code>
</a>
) on each
data node; these subdirectories are named
<code class="filename">
BACKUP-
<em class="replaceable">
<code>
backup_id
</code>
</em>
-PART-1-OF-
<em class="replaceable">
<code>
N
</code>
</em>
/
</code>
,
<code class="filename">
BACKUP-
<em class="replaceable">
<code>
backup_id
</code>
</em>
-PART-2-OF-
<em class="replaceable">
<code>
N
</code>
</em>
/
</code>
,
and so on, up to
<code class="filename">
BACKUP-
<em class="replaceable">
<code>
backup_id
</code>
</em>
-PART-
<em class="replaceable">
<code>
N
</code>
</em>
-OF-
<em class="replaceable">
<code>
N
</code>
</em>
/
</code>
,
where
<em class="replaceable">
<code>
backup_id
</code>
</em>
is the backup ID used
for this backup and
<em class="replaceable">
<code>
N
</code>
</em>
is the number
of LDMs per data node. Each of these subdirectories contains the
usual backup files
<code class="literal">
BACKUP-
<em class="replaceable">
<code>
backup_id
</code>
</em>
-0.
<em class="replaceable">
<code>
node_id
</code>
</em>
.Data
</code>
,
<code class="literal">
BACKUP-
<em class="replaceable">
<code>
backup_id
</code>
</em>
.
<em class="replaceable">
<code>
node_id
</code>
</em>
.ctl
</code>
,
and
<code class="literal">
BACKUP-backup_id.node_id.log
</code>
, where
<em class="replaceable">
<code>
node_id
</code>
</em>
is the node ID of this data
node.
</p>
<p>
<a class="link" href="mysql-cluster-programs-ndb-restore.html" title="25.5.23 ndb_restore — Restore an NDB Cluster Backup">
<span class="command">
<strong>
ndb_restore
</strong>
</span>
</a>
automatically checks for the
presence of the subdirectories just described; if it finds them,
it attempts to restore the backup in parallel. For information
about restoring backups taken with multiple LDMs, see
<a class="ulink" href="/doc/refman/8.0/en/ndb-restore-parallel-data-node-backup.html" target="_top">
Restoring from a backup taken in parallel
</a>
.
</p>
<p>
To force creation of a single-threaded backup, set
<a class="link" href="mysql-cluster-ndbd-definition.html#ndbparam-ndbmtd-enablemultithreadedbackup">
<code class="literal">
EnableMultithreadedBackup =
0
</code>
</a>
for all data nodes (you can do this by setting the
parameter in the
<code class="literal">
[ndbd default]
</code>
section of
the
<code class="filename">
config.ini
</code>
global configuration file).
It is also possible to restore a parallel backup to a cluster
running an older version of
<code class="filename">
NDB
</code>
. See
<a class="ulink" href="/doc/refman/8.0/en/ndb-restore-to-different-version.html#ndb-restore-to-previous-version" target="_top">
Restoring an NDB backup to a previous version of NDB Cluster
</a>
, for more
information.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-ndb-innodb-usage.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="mysql-cluster-ndb-innodb-usage">
</a>
25.2.6.3 NDB and InnoDB Feature Usage Summary
</h4>
</div>
</div>
</div>
<a class="indexterm" name="idm46045123713984">
</a>
<a class="indexterm" name="idm46045123712480">
</a>
<a class="indexterm" name="idm46045123710992">
</a>
<a class="indexterm" name="idm46045123709504">
</a>
<a class="indexterm" name="idm46045123708016">
</a>
<a class="indexterm" name="idm46045123706512">
</a>
<a class="indexterm" name="idm46045123705008">
</a>
<p>
When comparing application feature requirements to the
capabilities of
<a class="link" href="innodb-storage-engine.html" title="Chapter 17 The InnoDB Storage Engine">
<code class="literal">
InnoDB
</code>
</a>
with
<a class="link" href="mysql-cluster.html" title="Chapter 25 MySQL NDB Cluster 8.4">
<code class="literal">
NDB
</code>
</a>
, some are clearly more
compatible with one storage engine than the other.
</p>
<p>
The following table lists supported application features
according to the storage engine to which each feature is
typically better suited.
</p>
<div class="table">
<a name="idm46045123699920">
</a>
<p class="title">
<b>
Table 25.3 Supported application features according to the
storage engine to which each feature is typically better
suited
</b>
</p>
<div class="table-contents">
<table>
<colgroup>
<col style="width: 50%"/>
<col style="width: 50%"/>
</colgroup>
<thead>
<tr>
<th>
Preferred application requirements for
<a class="link" href="innodb-storage-engine.html" title="Chapter 17 The InnoDB Storage Engine">
<code class="literal">
InnoDB
</code>
</a>
</th>
<th>
Preferred application requirements for
<a class="link" href="mysql-cluster.html" title="Chapter 25 MySQL NDB Cluster 8.4">
<code class="literal">
NDB
</code>
</a>
</th>
</tr>
</thead>
<tbody>
<tr>
<td>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
Foreign keys
</p>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Note
</div>
<p>
NDB Cluster 8.4 supports foreign keys
</p>
</div>
</li>
<li class="listitem">
<p>
Full table scans
</p>
</li>
<li class="listitem">
<p>
Very large databases, rows, or transactions
</p>
</li>
<li class="listitem">
<p>
Transactions other than
<a class="link" href="innodb-transaction-isolation-levels.html#isolevel_read-committed">
<code class="literal">
READ COMMITTED
</code>
</a>
</p>
</li>
</ul>
</div>
</td>
<td>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
Write scaling
</p>
</li>
<li class="listitem">
<p>
99.999% uptime
</p>
</li>
<li class="listitem">
<p>
Online addition of nodes and online schema
operations
</p>
</li>
<li class="listitem">
<p>
Multiple SQL and NoSQL APIs (see
<a class="ulink" href="/doc/ndbapi/en/mysql-cluster-api-overview.html" target="_top">
NDB Cluster APIs: Overview and Concepts
</a>
)
</p>
</li>
<li class="listitem">
<p>
Real-time performance
</p>
</li>
<li class="listitem">
<p>
Limited use of
<a class="link" href="blob.html" title="13.3.4 The BLOB and TEXT Types">
<code class="literal">
BLOB
</code>
</a>
columns
</p>
</li>
<li class="listitem">
<p>
Foreign keys are supported, although their use may
have an impact on performance at high throughput
</p>
</li>
</ul>
</div>
</td>
</tr>
</tbody>
</table>
</div>
</div>
<br class="table-break"/>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/replication-solutions-backups-rawdata.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="replication-solutions-backups-rawdata">
</a>
19.4.1.2 Backing Up Raw Data from a Replica
</h4>
</div>
</div>
</div>
<p>
To guarantee the integrity of the files that are copied, backing
up the raw data files on your MySQL replica should take place
while your replica server is shut down. If the MySQL server is
still running, background tasks may still be updating the
database files, particularly those involving storage engines
with background processes such as
<code class="literal">
InnoDB
</code>
.
With
<code class="literal">
InnoDB
</code>
, these problems should be
resolved during crash recovery, but since the replica server can
be shut down during the backup process without affecting the
execution of the source it makes sense to take advantage of this
capability.
</p>
<p>
To shut down the server and back up the files:
</p>
<div class="orderedlist">
<ol class="orderedlist" type="1">
<li class="listitem">
<p>
Shut down the replica MySQL server:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-terminal"><div class="docs-select-all right" id="sa78023725"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal"><span class="token prompt">$> </span><span class="token command">mysqladmin</span> shutdown</code></pre>
</div>
</li>
<li class="listitem">
<p>
Copy the data files. You can use any suitable copying or
archive utility, including
<span class="command">
<strong>
cp
</strong>
</span>
,
<span class="command">
<strong>
tar
</strong>
</span>
or
<span class="command">
<strong>
WinZip
</strong>
</span>
. For
example, assuming that the data directory is located under
the current directory, you can archive the entire directory
as follows:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-terminal"><div class="docs-select-all right" id="sa27904775"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal"><span class="token prompt">$> </span><span class="token command">tar</span> cf /tmp/dbbackup<span class="token punctuation">.</span>tar <span class="token punctuation">.</span>/data</code></pre>
</div>
</li>
<li class="listitem">
<p>
Start the MySQL server again. Under Unix:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-terminal"><div class="docs-select-all right" id="sa42391753"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal"><span class="token prompt">$> </span><span class="token command">mysqld_safe</span> &</code></pre>
</div>
<p>
Under Windows:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-terminal"><div class="docs-select-all right" id="sa29132836"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal"><span class="token prompt">C:\></span> <span class="token atrule">"C:\Program Files\MySQL\MySQL Server 8.4\bin\mysqld"</span></code></pre>
</div>
</li>
</ol>
</div>
<p>
Normally you should back up the entire data directory for the
replica MySQL server. If you want to be able to restore the data
and operate as a replica (for example, in the event of failure
of the replica), in addition to the data, you need to have the
replica's connection metadata repository and applier metadata
repository, and the relay log files. These items are needed to
resume replication after you restore the replica's data.
Assuming tables have been used for the replica's connection
metadata repository and applier metadata repository (see
<a class="xref" href="replica-logs.html" title="19.2.4 Relay Log and Replication Metadata Repositories">
Section 19.2.4, “Relay Log and Replication Metadata Repositories”
</a>
), which is the default in MySQL
8.4, these tables are backed up along with the data
directory. If files have been used for the repositories, which
is deprecated, you must back these up separately. The relay log
files must be backed up separately if they have been placed in a
different location to the data directory.
</p>
<p>
If you lose the relay logs but still have the
<code class="filename">
relay-log.info
</code>
file, you can check it to
determine how far the replication SQL thread has executed in the
source's binary logs. Then you can use
<a class="link" href="change-replication-source-to.html" title="15.4.2.2 CHANGE REPLICATION SOURCE TO Statement">
<code class="literal">
CHANGE REPLICATION SOURCE TO
</code>
</a>
with
the
<code class="literal">
SOURCE_LOG_FILE
</code>
and
<code class="literal">
SOURCE_LOG_POS
</code>
options to tell the replica to
re-read the binary logs from that point. This requires that the
binary logs still exist on the source server.
</p>
<p>
If your replica is replicating
<a class="link" href="load-data.html" title="15.2.9 LOAD DATA Statement">
<code class="literal">
LOAD
DATA
</code>
</a>
statements, you should also back up any
<code class="filename">
SQL_LOAD-*
</code>
files that exist in the
directory that the replica uses for this purpose. The replica
needs these files to resume replication of any interrupted
<a class="link" href="load-data.html" title="15.2.9 LOAD DATA Statement">
<code class="literal">
LOAD DATA
</code>
</a>
operations. The
location of this directory is the value of the system variable
<a class="link" href="replication-options-replica.html#sysvar_replica_load_tmpdir">
<code class="literal">
replica_load_tmpdir
</code>
</a>
. If the
server was not started with that variable set, the directory
location is the value of the
<a class="link" href="server-system-variables.html#sysvar_tmpdir">
<code class="literal">
tmpdir
</code>
</a>
system variable.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-ndbinfo-config-nodes.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="mysql-cluster-ndbinfo-config-nodes">
</a>
25.6.17.10 The ndbinfo config_nodes Table
</h4>
</div>
</div>
</div>
<a class="indexterm" name="idm46045090224400">
</a>
<p>
The
<code class="literal">
config_nodes
</code>
table shows nodes configured
in an NDB Cluster
<code class="filename">
config.ini
</code>
file. For each
node, the table displays a row containing the node ID, the type
of node (management node, data node, or API node), and the name
or IP address of the host on which the node is configured to
run.
</p>
<p>
This table does not indicate whether a given node is actually
running, or whether it is currently connected to the cluster.
Information about nodes connected to an NDB Cluster can be
obtained from the
<a class="link" href="mysql-cluster-ndbinfo-nodes.html" title="25.6.17.48 The ndbinfo nodes Table">
<code class="literal">
nodes
</code>
</a>
and
<a class="link" href="mysql-cluster-ndbinfo-processes.html" title="25.6.17.51 The ndbinfo processes Table">
<code class="literal">
processes
</code>
</a>
table.
</p>
<p>
The
<code class="literal">
config_nodes
</code>
table contains the following
columns:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<code class="literal">
node_id
</code>
</p>
<p>
The node's ID
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
node_type
</code>
</p>
<p>
The type of node
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
node_hostname
</code>
</p>
<p>
The name or IP address of the host on which the node resides
</p>
</li>
</ul>
</div>
<h5>
<a name="idm46045090210208">
</a>
Notes
</h5>
<p>
The
<code class="literal">
node_id
</code>
column shows the node ID used in
the
<code class="filename">
config.ini
</code>
file for this node; if none
is specified, the node ID that would be assigned automatically
to this node is displayed.
</p>
<p>
The
<code class="literal">
node_type
</code>
column displays one of the
following three values:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<code class="literal">
MGM
</code>
: Management node.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
NDB
</code>
: Data node.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
API
</code>
: API node; this includes SQL nodes.
</p>
</li>
</ul>
</div>
<p>
The
<code class="literal">
node_hostname
</code>
column shows the node host
as specified in the
<code class="filename">
config.ini
</code>
file. This
can be empty for an API node, if
<a class="link" href="mysql-cluster-api-definition.html#ndbparam-api-hostname">
<code class="literal">
HostName
</code>
</a>
has not been set
in the cluster configuration file. If
<a class="link" href="mysql-cluster-ndbd-definition.html#ndbparam-ndbd-hostname">
<code class="literal">
HostName
</code>
</a>
has not been
set for a data node in the configuration file,
<code class="literal">
localhost
</code>
is used here.
<code class="literal">
localhost
</code>
is also used if
<a class="link" href="mysql-cluster-mgm-definition.html#ndbparam-mgmd-hostname">
<code class="literal">
HostName
</code>
</a>
has not been
specified for a management node.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/innodb-tablespace.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="innodb-tablespace">
</a>
17.6.3 Tablespaces
</h3>
</div>
</div>
</div>
<div class="toc">
<dl class="toc">
<dt>
<span class="section">
<a href="innodb-system-tablespace.html">
17.6.3.1 The System Tablespace
</a>
</span>
</dt>
<dt>
<span class="section">
<a href="innodb-file-per-table-tablespaces.html">
17.6.3.2 File-Per-Table Tablespaces
</a>
</span>
</dt>
<dt>
<span class="section">
<a href="general-tablespaces.html">
17.6.3.3 General Tablespaces
</a>
</span>
</dt>
<dt>
<span class="section">
<a href="innodb-undo-tablespaces.html">
17.6.3.4 Undo Tablespaces
</a>
</span>
</dt>
<dt>
<span class="section">
<a href="innodb-temporary-tablespace.html">
17.6.3.5 Temporary Tablespaces
</a>
</span>
</dt>
<dt>
<span class="section">
<a href="innodb-moving-data-files-offline.html">
17.6.3.6 Moving Tablespace Files While the Server is Offline
</a>
</span>
</dt>
<dt>
<span class="section">
<a href="innodb-disabling-tablespace-path-validation.html">
17.6.3.7 Disabling Tablespace Path Validation
</a>
</span>
</dt>
<dt>
<span class="section">
<a href="innodb-optimize-tablespace-page-allocation.html">
17.6.3.8 Optimizing Tablespace Space Allocation on Linux
</a>
</span>
</dt>
<dt>
<span class="section">
<a href="innodb-tablespace-autoextend-size.html">
17.6.3.9 Tablespace AUTOEXTEND_SIZE Configuration
</a>
</span>
</dt>
</dl>
</div>
<p>
This section covers topics related to
<code class="literal">
InnoDB
</code>
tablespaces.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/group-replication-replication-technologies.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="group-replication-replication-technologies">
</a>
20.1.1 Replication Technologies
</h3>
</div>
</div>
</div>
<div class="toc">
<dl class="toc">
<dt>
<span class="section">
<a href="group-replication-primary-secondary-replication.html">
20.1.1.1 Source to Replica Replication
</a>
</span>
</dt>
<dt>
<span class="section">
<a href="group-replication-summary.html">
20.1.1.2 Group Replication
</a>
</span>
</dt>
</dl>
</div>
<a class="indexterm" name="idm46045134578736">
</a>
<a class="indexterm" name="idm46045134577232">
</a>
<p>
Before getting into the details of MySQL Group Replication, this
section introduces some background concepts and an overview of how
things work. This provides some context to help understand what is
required for Group Replication and what the differences are
between classic asynchronous MySQL Replication and Group
Replication.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-tde.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="mysql-cluster-tde">
</a>
25.6.14 File System Encryption for NDB Cluster
</h3>
</div>
</div>
</div>
<div class="toc">
<dl class="toc">
<dt>
<span class="section">
<a href="mysql-cluster-tde-setup.html">
25.6.14.1 NDB File System Encryption Setup and Usage
</a>
</span>
</dt>
<dt>
<span class="section">
<a href="mysql-cluster-tde-implementation.html">
25.6.14.2 NDB File System Encryption Implementation
</a>
</span>
</dt>
<dt>
<span class="section">
<a href="mysql-cluster-tde-limitations.html">
25.6.14.3 NDB File System Encryption Limitations
</a>
</span>
</dt>
</dl>
</div>
<p>
The following sections provide information about
<code class="literal">
NDB
</code>
data node file system encryption.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/keyring-service.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="keyring-service">
</a>
7.6.9.2 The Keyring Service
</h4>
</div>
</div>
</div>
<a class="indexterm" name="idm46045254330512">
</a>
<a class="indexterm" name="idm46045254329024">
</a>
<p>
MySQL Server supports a keyring service that enables internal
components and plugins to securely store sensitive information
for later retrieval. MySQL distributions provide a keyring
interface that is accessible at two levels:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
At the SQL level, as a set of loadable functions that each
map onto calls to the service routines.
</p>
</li>
<li class="listitem">
<p>
As a C language interface, callable as a plugin service from
server plugins or loadable functions.
</p>
</li>
</ul>
</div>
<p>
This section describes how to use the keyring service functions
to store, retrieve, and remove keys in the MySQL keyring
keystore. For information about the SQL interface that uses
functions,
<a class="xref" href="keyring-functions-general-purpose.html" title="8.4.4.12 General-Purpose Keyring Key-Management Functions">
Section 8.4.4.12, “General-Purpose Keyring Key-Management Functions”
</a>
.
For general keyring information, see
<a class="xref" href="keyring.html" title="8.4.4 The MySQL Keyring">
Section 8.4.4, “The MySQL Keyring”
</a>
.
</p>
<p>
The keyring service uses whatever underlying keyring plugin is
enabled, if any. If no keyring plugin is enabled, keyring
service calls fail.
</p>
<p>
A
<span class="quote">
“
<span class="quote">
record
</span>
”
</span>
in the keystore consists of data (the
key itself) and a unique identifier through which the key is
accessed. The identifier has two parts:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<code class="literal">
key_id
</code>
: The key ID or name.
<code class="literal">
key_id
</code>
values that begin with
<code class="literal">
mysql_
</code>
are reserved by MySQL Server.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
user_id
</code>
: The session effective user ID.
If there is no user context, this value can be
<code class="literal">
NULL
</code>
. The value need not actually be a
<span class="quote">
“
<span class="quote">
user
</span>
”
</span>
; the meaning depends on the application.
</p>
<p>
Functions that implement the keyring function interface pass
the value of
<a class="link" href="information-functions.html#function_current-user">
<code class="literal">
CURRENT_USER()
</code>
</a>
as the
<code class="literal">
user_id
</code>
value to keyring service
functions.
</p>
</li>
</ul>
</div>
<p>
The keyring service functions have these characteristics in
common:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
Each function returns 0 for success, 1 for failure.
</p>
</li>
<li class="listitem">
<p>
The
<code class="literal">
key_id
</code>
and
<code class="literal">
user_id
</code>
arguments form a unique combination indicating which key in
the keyring to use.
</p>
</li>
<li class="listitem">
<p>
The
<code class="literal">
key_type
</code>
argument provides additional
information about the key, such as its encryption method or
intended use.
</p>
</li>
<li class="listitem">
<p>
Keyring service functions treat key IDs, user names, types,
and values as binary strings, so comparisons are
case-sensitive. For example, IDs of
<code class="literal">
MyKey
</code>
and
<code class="literal">
mykey
</code>
refer to different keys.
</p>
</li>
</ul>
</div>
<p>
These keyring service functions are available:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<code class="literal">
my_key_fetch()
</code>
</p>
<a class="indexterm" name="idm46045254302400">
</a>
<a class="indexterm" name="idm46045254301312">
</a>
<p>
Deobfuscates and retrieves a key from the keyring, along
with its type. The function allocates the memory for the
buffers used to store the returned key and key type. The
caller should zero or obfuscate the memory when it is no
longer needed, then free it.
</p>
<p>
Syntax:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-c"><div class="docs-select-all right" id="sa41835447"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-c">bool <span class="token function">my_key_fetch</span><span class="token punctuation">(</span><span class="token keyword">const</span> <span class="token keyword">char</span> <span class="token operator">*</span>key_id<span class="token punctuation">,</span> <span class="token keyword">const</span> <span class="token keyword">char</span> <span class="token operator">*</span><span class="token operator">*</span>key_type<span class="token punctuation">,</span>
<span class="token keyword">const</span> <span class="token keyword">char</span><span class="token operator">*</span> user_id<span class="token punctuation">,</span> <span class="token keyword">void</span> <span class="token operator">*</span><span class="token operator">*</span>key<span class="token punctuation">,</span> size_t <span class="token operator">*</span>key_len<span class="token punctuation">)</span></code></pre>
</div>
<p>
Arguments:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
<code class="literal">
key_id
</code>
,
<code class="literal">
user_id
</code>
:
Null-terminated strings that as a pair form a unique
identifier indicating which key to fetch.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
key_type
</code>
: The address of a buffer
pointer. The function stores into it a pointer to a
null-terminated string that provides additional
information about the key (stored when the key was
added).
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
key
</code>
: The address of a buffer pointer.
The function stores into it a pointer to the buffer
containing the fetched key data.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
key_len
</code>
: The address of a variable
into which the function stores the size in bytes of the
<code class="literal">
*key
</code>
buffer.
</p>
</li>
</ul>
</div>
<p>
Return value:
</p>
<p>
Returns 0 for success, 1 for failure.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
my_key_generate()
</code>
</p>
<a class="indexterm" name="idm46045254286496">
</a>
<a class="indexterm" name="idm46045254285392">
</a>
<p>
Generates a new random key of a given type and length and
stores it in the keyring. The key has a length of
<code class="literal">
key_len
</code>
and is associated with the
identifier formed from
<code class="literal">
key_id
</code>
and
<code class="literal">
user_id
</code>
. The type and length values must
be consistent with the values supported by the underlying
keyring plugin. See
<a class="xref" href="keyring-key-types.html" title="8.4.4.10 Supported Keyring Key Types and Lengths">
Section 8.4.4.10, “Supported Keyring Key Types and Lengths”
</a>
.
</p>
<p>
Syntax:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-c"><div class="docs-select-all right" id="sa94271826"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-c">bool <span class="token function">my_key_generate</span><span class="token punctuation">(</span><span class="token keyword">const</span> <span class="token keyword">char</span> <span class="token operator">*</span>key_id<span class="token punctuation">,</span> <span class="token keyword">const</span> <span class="token keyword">char</span> <span class="token operator">*</span>key_type<span class="token punctuation">,</span>
<span class="token keyword">const</span> <span class="token keyword">char</span> <span class="token operator">*</span>user_id<span class="token punctuation">,</span> size_t key_len<span class="token punctuation">)</span></code></pre>
</div>
<p>
Arguments:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
<code class="literal">
key_id
</code>
,
<code class="literal">
user_id
</code>
:
Null-terminated strings that as a pair form a unique
identifier for the key to be generated.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
key_type
</code>
: A null-terminated string
that provides additional information about the key.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
key_len
</code>
: The size in bytes of the key
to be generated.
</p>
</li>
</ul>
</div>
<p>
Return value:
</p>
<p>
Returns 0 for success, 1 for failure.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
my_key_remove()
</code>
</p>
<a class="indexterm" name="idm46045254270128">
</a>
<a class="indexterm" name="idm46045254269024">
</a>
<p>
Removes a key from the keyring.
</p>
<p>
Syntax:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-c"><div class="docs-select-all right" id="sa85380486"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-c">bool <span class="token function">my_key_remove</span><span class="token punctuation">(</span><span class="token keyword">const</span> <span class="token keyword">char</span> <span class="token operator">*</span>key_id<span class="token punctuation">,</span> <span class="token keyword">const</span> <span class="token keyword">char</span><span class="token operator">*</span> user_id<span class="token punctuation">)</span></code></pre>
</div>
<p>
Arguments:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
<code class="literal">
key_id
</code>
,
<code class="literal">
user_id
</code>
:
Null-terminated strings that as a pair form a unique
identifier for the key to be removed.
</p>
</li>
</ul>
</div>
<p>
Return value:
</p>
<p>
Returns 0 for success, 1 for failure.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
my_key_store()
</code>
</p>
<a class="indexterm" name="idm46045254260192">
</a>
<a class="indexterm" name="idm46045254259104">
</a>
<p>
Obfuscates and stores a key in the keyring.
</p>
<p>
Syntax:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-c"><div class="docs-select-all right" id="sa16892601"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-c">bool <span class="token function">my_key_store</span><span class="token punctuation">(</span><span class="token keyword">const</span> <span class="token keyword">char</span> <span class="token operator">*</span>key_id<span class="token punctuation">,</span> <span class="token keyword">const</span> <span class="token keyword">char</span> <span class="token operator">*</span>key_type<span class="token punctuation">,</span>
<span class="token keyword">const</span> <span class="token keyword">char</span><span class="token operator">*</span> user_id<span class="token punctuation">,</span> <span class="token keyword">void</span> <span class="token operator">*</span>key<span class="token punctuation">,</span> size_t key_len<span class="token punctuation">)</span></code></pre>
</div>
<p>
Arguments:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
<code class="literal">
key_id
</code>
,
<code class="literal">
user_id
</code>
:
Null-terminated strings that as a pair form a unique
identifier for the key to be stored.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
key_type
</code>
: A null-terminated string
that provides additional information about the key.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
key
</code>
: The buffer containing the key
data to be stored.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
key_len
</code>
: The size in bytes of the
<code class="literal">
key
</code>
buffer.
</p>
</li>
</ul>
</div>
<p>
Return value:
</p>
<p>
Returns 0 for success, 1 for failure.
</p>
</li>
</ul>
</div>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-programs-ndbinfo-select-all.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="mysql-cluster-programs-ndbinfo-select-all">
</a>
25.5.2 ndbinfo_select_all — Select From ndbinfo Tables
</h3>
</div>
</div>
</div>
<a class="indexterm" name="idm46045107677152">
</a>
<a class="indexterm" name="idm46045107676208">
</a>
<p>
<a class="link" href="mysql-cluster-programs-ndbinfo-select-all.html" title="25.5.2 ndbinfo_select_all — Select From ndbinfo Tables">
<span class="command">
<strong>
ndbinfo_select_all
</strong>
</span>
</a>
is a client program that
selects all rows and columns from one or more tables in the
<a class="link" href="mysql-cluster-ndbinfo.html" title="25.6.17 ndbinfo: The NDB Cluster Information Database">
<code class="literal">
ndbinfo
</code>
</a>
database
</p>
<p>
Not all
<code class="literal">
ndbinfo
</code>
tables available in the
<a class="link" href="mysql.html" title="6.5.1 mysql — The MySQL Command-Line Client">
<span class="command">
<strong>
mysql
</strong>
</span>
</a>
client can be read by this program (see
later in this section). In addition,
<a class="link" href="mysql-cluster-programs-ndbinfo-select-all.html" title="25.5.2 ndbinfo_select_all — Select From ndbinfo Tables">
<span class="command">
<strong>
ndbinfo_select_all
</strong>
</span>
</a>
can show information about
some tables internal to
<code class="literal">
ndbinfo
</code>
which cannot
be accessed using SQL, including the
<code class="literal">
tables
</code>
and
<code class="literal">
columns
</code>
metadata tables.
</p>
<p>
To select from one or more
<code class="literal">
ndbinfo
</code>
tables
using
<a class="link" href="mysql-cluster-programs-ndbinfo-select-all.html" title="25.5.2 ndbinfo_select_all — Select From ndbinfo Tables">
<span class="command">
<strong>
ndbinfo_select_all
</strong>
</span>
</a>
, it is necessary to
supply the names of the tables when invoking the program as
shown here:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-terminal"><div class="docs-select-all right" id="sa56598198"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal"><span class="token prompt">$> </span><span class="token command">ndbinfo_select_all</span> <em class="replaceable">table_name1</em> <span class="token punctuation">[</span><em class="replaceable">table_name2</em><span class="token punctuation">]</span> <span class="token punctuation">[</span><span class="token punctuation">.</span><span class="token punctuation">.</span><span class="token punctuation">.</span><span class="token punctuation">]</span></code></pre>
</div>
<p>
For example:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-terminal"><div class="docs-select-all right" id="sa81453036"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal"><span class="token prompt">$> </span><span class="token command">ndbinfo_select_all</span> logbuffers logspaces
<span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">=</span></span> logbuffers <span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">=</span></span>
node_id log_type log_id log_part total used high
5 0 0 0 33554432 262144 0
6 0 0 0 33554432 262144 0
7 0 0 0 33554432 262144 0
8 0 0 0 33554432 262144 0
<span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">=</span></span> logspaces <span class="token attr-value"><span class="token punctuation">=</span><span class="token punctuation">=</span></span>
node_id log_type log_id log_part total used high
5 0 0 0 268435456 0 0
5 0 0 1 268435456 0 0
5 0 0 2 268435456 0 0
5 0 0 3 268435456 0 0
6 0 0 0 268435456 0 0
6 0 0 1 268435456 0 0
6 0 0 2 268435456 0 0
6 0 0 3 268435456 0 0
7 0 0 0 268435456 0 0
7 0 0 1 268435456 0 0
7 0 0 2 268435456 0 0
7 0 0 3 268435456 0 0
8 0 0 0 268435456 0 0
8 0 0 1 268435456 0 0
8 0 0 2 268435456 0 0
8 0 0 3 268435456 0 0
$></code></pre>
</div>
<a class="indexterm" name="idm46045107655680">
</a>
<p>
Options that can be used with
<a class="link" href="mysql-cluster-programs-ndbinfo-select-all.html" title="25.5.2 ndbinfo_select_all — Select From ndbinfo Tables">
<span class="command">
<strong>
ndbinfo_select_all
</strong>
</span>
</a>
are shown in the following
table. Additional descriptions follow the table.
</p>
<p>
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<a name="option_ndbinfo_select_all_character-sets-dir">
</a>
<a class="link" href="mysql-cluster-programs-ndbinfo-select-all.html#option_ndbinfo_select_all_character-sets-dir">
<code class="option">
--character-sets-dir
</code>
</a>
</p>
<a class="indexterm" name="idm46045107649296">
</a>
<a class="indexterm" name="idm46045107647792">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for character-sets-dir">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--character-sets-dir=path
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Directory containing character sets.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndbinfo_select_all_core-file">
</a>
<a class="link" href="mysql-cluster-programs-ndbinfo-select-all.html#option_ndbinfo_select_all_core-file">
<code class="option">
--core-file
</code>
</a>
</p>
<a class="indexterm" name="idm46045107638000">
</a>
<a class="indexterm" name="idm46045107636512">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for core-file">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--core-file
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Write core file on error; used in debugging.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndbinfo_select_all_connect-retries">
</a>
<a class="link" href="mysql-cluster-programs-ndbinfo-select-all.html#option_ndbinfo_select_all_connect-retries">
<code class="option">
--connect-retries
</code>
</a>
</p>
<a class="indexterm" name="idm46045107626656">
</a>
<a class="indexterm" name="idm46045107625168">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for connect-retries">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--connect-retries=#
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Integer
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
12
</code>
</td>
</tr>
<tr>
<th>
Minimum Value
</th>
<td>
<code class="literal">
0
</code>
</td>
</tr>
<tr>
<th>
Maximum Value
</th>
<td>
<code class="literal">
12
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Number of times to retry connection before giving up.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndbinfo_select_all_connect-retry-delay">
</a>
<a class="link" href="mysql-cluster-programs-ndbinfo-select-all.html#option_ndbinfo_select_all_connect-retry-delay">
<code class="option">
--connect-retry-delay
</code>
</a>
</p>
<a class="indexterm" name="idm46045107606016">
</a>
<a class="indexterm" name="idm46045107604512">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for connect-retry-delay">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--connect-retry-delay=#
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Integer
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
5
</code>
</td>
</tr>
<tr>
<th>
Minimum Value
</th>
<td>
<code class="literal">
0
</code>
</td>
</tr>
<tr>
<th>
Maximum Value
</th>
<td>
<code class="literal">
5
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Number of seconds to wait between attempts to contact
management server.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndbinfo_select_all_connect-string">
</a>
<a class="link" href="mysql-cluster-programs-ndbinfo-select-all.html#option_ndbinfo_select_all_connect-string">
<code class="option">
--connect-string
</code>
</a>
</p>
<a class="indexterm" name="idm46045107585248">
</a>
<a class="indexterm" name="idm46045107583760">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for connect-string">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--connect-string=connection-string
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
String
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
[none]
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Same as
<a class="link" href="mysql-cluster-programs-ndbinfo-select-all.html#option_ndbinfo_select_all_ndb-connectstring">
<code class="option">
--ndb-connectstring
</code>
</a>
.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndbinfo_select_all_defaults-extra-file">
</a>
<a class="link" href="mysql-cluster-programs-ndbinfo-select-all.html#option_ndbinfo_select_all_defaults-extra-file">
<code class="option">
--defaults-extra-file
</code>
</a>
</p>
<a class="indexterm" name="idm46045107568304">
</a>
<a class="indexterm" name="idm46045107566800">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for defaults-extra-file">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--defaults-extra-file=path
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
String
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
[none]
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Read given file after global files are read.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndbinfo_select_all_defaults-file">
</a>
<a class="link" href="mysql-cluster-programs-ndbinfo-select-all.html#option_ndbinfo_select_all_defaults-file">
<code class="option">
--defaults-file
</code>
</a>
</p>
<a class="indexterm" name="idm46045107552576">
</a>
<a class="indexterm" name="idm46045107551088">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for defaults-file">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--defaults-file=path
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
String
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
[none]
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Read default options from given file only.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndbinfo_select_all_defaults-group-suffix">
</a>
<a class="link" href="mysql-cluster-programs-ndbinfo-select-all.html#option_ndbinfo_select_all_defaults-group-suffix">
<code class="option">
--defaults-group-suffix
</code>
</a>
</p>
<a class="indexterm" name="idm46045107536800">
</a>
<a class="indexterm" name="idm46045107535296">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for defaults-group-suffix">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--defaults-group-suffix=string
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
String
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
[none]
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Also read groups with concat(group, suffix).
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndbinfo_select_all_delay">
</a>
<a class="link" href="mysql-cluster-programs-ndbinfo-select-all.html#option_ndbinfo_select_all_delay">
<code class="option">
--delay=
<code class="literal">
seconds
</code>
</code>
</a>
</p>
<a class="indexterm" name="idm46045107520512">
</a>
<a class="indexterm" name="idm46045107519024">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for delay">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--delay=#
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Numeric
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
5
</code>
</td>
</tr>
<tr>
<th>
Minimum Value
</th>
<td>
<code class="literal">
0
</code>
</td>
</tr>
<tr>
<th>
Maximum Value
</th>
<td>
<code class="literal">
MAX_INT
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
This option sets the number of seconds to wait between
executing loops. Has no effect if
<a class="link" href="mysql-cluster-programs-ndbinfo-select-all.html#option_ndbinfo_select_all_loops">
<code class="option">
--loops
</code>
</a>
is set to
0 or 1.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndbinfo_select_all_help">
</a>
<a class="link" href="mysql-cluster-programs-ndbinfo-select-all.html#option_ndbinfo_select_all_help">
<code class="option">
--help
</code>
</a>
</p>
<a class="indexterm" name="idm46045107498800">
</a>
<a class="indexterm" name="idm46045107497312">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for help">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--help
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Display help text and exit.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndbinfo_select_all_login-path">
</a>
<a class="link" href="mysql-cluster-programs-ndbinfo-select-all.html#option_ndbinfo_select_all_login-path">
<code class="option">
--login-path
</code>
</a>
</p>
<a class="indexterm" name="idm46045107487568">
</a>
<a class="indexterm" name="idm46045107486080">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for login-path">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--login-path=path
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
String
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
[none]
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Read given path from login file.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndbinfo_select_all_no-login-paths">
</a>
<a class="link" href="mysql-cluster-programs-ndbinfo-select-all.html#option_ndbinfo_select_all_no-login-paths">
<code class="option">
--no-login-paths
</code>
</a>
</p>
<a class="indexterm" name="idm46045107471792">
</a>
<a class="indexterm" name="idm46045107470304">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for no-login-paths">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--no-login-paths
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Skips reading options from the login path file.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndbinfo_select_all_loops">
</a>
<a class="link" href="mysql-cluster-programs-ndbinfo-select-all.html#option_ndbinfo_select_all_loops">
<code class="option">
--loops=
<code class="literal">
number
</code>
</code>
</a>
,
<code class="option">
-l
<em class="replaceable">
<code>
number
</code>
</em>
</code>
</p>
<a class="indexterm" name="idm46045107459392">
</a>
<a class="indexterm" name="idm46045107457904">
</a>
<a class="indexterm" name="idm46045107456416">
</a>
<a class="indexterm" name="idm46045107454928">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for loops">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--loops=#
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Numeric
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
1
</code>
</td>
</tr>
<tr>
<th>
Minimum Value
</th>
<td>
<code class="literal">
0
</code>
</td>
</tr>
<tr>
<th>
Maximum Value
</th>
<td>
<code class="literal">
MAX_INT
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
This option sets the number of times to execute the select.
Use
<a class="link" href="mysql-cluster-programs-ndbinfo-select-all.html#option_ndbinfo_select_all_delay">
<code class="option">
--delay
</code>
</a>
to
set the time between loops.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndbinfo_select_all_ndb-connectstring">
</a>
<a class="link" href="mysql-cluster-programs-ndbinfo-select-all.html#option_ndbinfo_select_all_ndb-connectstring">
<code class="option">
--ndb-connectstring
</code>
</a>
</p>
<a class="indexterm" name="idm46045107434880">
</a>
<a class="indexterm" name="idm46045107433376">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for ndb-connectstring">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--ndb-connectstring=connection-string
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
String
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
[none]
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Set connection string for connecting to
<a class="link" href="mysql-cluster-programs-ndb-mgmd.html" title="25.5.4 ndb_mgmd — The NDB Cluster Management Server Daemon">
<span class="command">
<strong>
ndb_mgmd
</strong>
</span>
</a>
. Syntax:
<code class="literal">
[nodeid=
<em class="replaceable">
<code>
id
</code>
</em>
;][host=]
<em class="replaceable">
<code>
hostname
</code>
</em>
[:
<em class="replaceable">
<code>
port
</code>
</em>
]
</code>
.
Overrides entries in
<code class="literal">
NDB_CONNECTSTRING
</code>
and
<code class="filename">
my.cnf
</code>
.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndbinfo_select_all_ndb-mgmd-host">
</a>
<a class="link" href="mysql-cluster-programs-ndbinfo-select-all.html#option_ndbinfo_select_all_ndb-mgmd-host">
<code class="option">
--ndb-mgmd-host
</code>
</a>
</p>
<a class="indexterm" name="idm46045107414464">
</a>
<a class="indexterm" name="idm46045107412976">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for ndb-mgmd-host">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--ndb-mgmd-host=connection-string
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
String
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
[none]
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Same as
<a class="link" href="mysql-cluster-programs-ndbinfo-select-all.html#option_ndbinfo_select_all_ndb-connectstring">
<code class="option">
--ndb-connectstring
</code>
</a>
.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndbinfo_select_all_ndb-nodeid">
</a>
<a class="link" href="mysql-cluster-programs-ndbinfo-select-all.html#option_ndbinfo_select_all_ndb-nodeid">
<code class="option">
--ndb-nodeid
</code>
</a>
</p>
<a class="indexterm" name="idm46045107397632">
</a>
<a class="indexterm" name="idm46045107396144">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for ndb-nodeid">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--ndb-nodeid=#
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Integer
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
[none]
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Set node ID for this node, overriding any ID set by
--ndb-connectstring.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndbinfo_select_all_ndb-optimized-node-selection">
</a>
<a class="link" href="mysql-cluster-programs-ndbinfo-select-all.html#option_ndbinfo_select_all_ndb-optimized-node-selection">
<code class="option">
--ndb-optimized-node-selection
</code>
</a>
</p>
<a class="indexterm" name="idm46045107381792">
</a>
<a class="indexterm" name="idm46045107380288">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for ndb-optimized-node-selection">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--ndb-optimized-node-selection
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Enable optimizations for selection of nodes for
transactions. Enabled by default; use
<code class="option">
--skip-ndb-optimized-node-selection
</code>
to
disable.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndbinfo_select_all_no-defaults">
</a>
<a class="link" href="mysql-cluster-programs-ndbinfo-select-all.html#option_ndbinfo_select_all_no-defaults">
<code class="option">
--no-defaults
</code>
</a>
</p>
<a class="indexterm" name="idm46045107370000">
</a>
<a class="indexterm" name="idm46045107368512">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for no-defaults">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--no-defaults
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Do not read default options from any option file other than
login file.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndbinfo_select_all_print-defaults">
</a>
<a class="link" href="mysql-cluster-programs-ndbinfo-select-all.html#option_ndbinfo_select_all_print-defaults">
<code class="option">
--print-defaults
</code>
</a>
</p>
<a class="indexterm" name="idm46045107358608">
</a>
<a class="indexterm" name="idm46045107357120">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for print-defaults">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--print-defaults
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Print program argument list and exit.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndbinfo_select_all_usage">
</a>
<a class="link" href="mysql-cluster-programs-ndbinfo-select-all.html#option_ndbinfo_select_all_usage">
<code class="option">
--usage
</code>
</a>
</p>
<a class="indexterm" name="idm46045107347360">
</a>
<a class="indexterm" name="idm46045107345872">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for usage">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--usage
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Display help text and exit; same as --help.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndbinfo_select_all_version">
</a>
<a class="link" href="mysql-cluster-programs-ndbinfo-select-all.html#option_ndbinfo_select_all_version">
<code class="option">
--version
</code>
</a>
</p>
<a class="indexterm" name="idm46045107336112">
</a>
<a class="indexterm" name="idm46045107334624">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for version">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--version
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Display version information and exit.
</p>
</li>
</ul>
</div>
<p>
<a class="link" href="mysql-cluster-programs-ndbinfo-select-all.html" title="25.5.2 ndbinfo_select_all — Select From ndbinfo Tables">
<span class="command">
<strong>
ndbinfo_select_all
</strong>
</span>
</a>
is unable to read the
following tables:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<a class="link" href="mysql-cluster-ndbinfo-arbitrator-validity-detail.html" title="25.6.17.1 The ndbinfo arbitrator_validity_detail Table">
<code class="literal">
arbitrator_validity_detail
</code>
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="mysql-cluster-ndbinfo-arbitrator-validity-summary.html" title="25.6.17.2 The ndbinfo arbitrator_validity_summary Table">
<code class="literal">
arbitrator_validity_summary
</code>
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="mysql-cluster-ndbinfo-cluster-locks.html" title="25.6.17.7 The ndbinfo cluster_locks Table">
<code class="literal">
cluster_locks
</code>
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="mysql-cluster-ndbinfo-cluster-operations.html" title="25.6.17.8 The ndbinfo cluster_operations Table">
<code class="literal">
cluster_operations
</code>
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="mysql-cluster-ndbinfo-cluster-transactions.html" title="25.6.17.9 The ndbinfo cluster_transactions Table">
<code class="literal">
cluster_transactions
</code>
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="mysql-cluster-ndbinfo-disk-write-speed-aggregate-node.html" title="25.6.17.30 The ndbinfo disk_write_speed_aggregate_node Table">
<code class="literal">
disk_write_speed_aggregate_node
</code>
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="mysql-cluster-ndbinfo-locks-per-fragment.html" title="25.6.17.42 The ndbinfo locks_per_fragment Table">
<code class="literal">
locks_per_fragment
</code>
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="mysql-cluster-ndbinfo-memory-per-fragment.html" title="25.6.17.47 The ndbinfo memory_per_fragment Table">
<code class="literal">
memory_per_fragment
</code>
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="mysql-cluster-ndbinfo-memoryusage.html" title="25.6.17.46 The ndbinfo memoryusage Table">
<code class="literal">
memoryusage
</code>
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="mysql-cluster-ndbinfo-operations-per-fragment.html" title="25.6.17.49 The ndbinfo operations_per_fragment Table">
<code class="literal">
operations_per_fragment
</code>
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="mysql-cluster-ndbinfo-server-locks.html" title="25.6.17.54 The ndbinfo server_locks Table">
<code class="literal">
server_locks
</code>
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="mysql-cluster-ndbinfo-server-operations.html" title="25.6.17.55 The ndbinfo server_operations Table">
<code class="literal">
server_operations
</code>
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="mysql-cluster-ndbinfo-server-transactions.html" title="25.6.17.56 The ndbinfo server_transactions Table">
<code class="literal">
server_transactions
</code>
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="mysql-cluster-ndbinfo-table-info.html" title="25.6.17.59 The ndbinfo table_info Table">
<code class="literal">
table_info
</code>
</a>
</p>
</li>
</ul>
</div>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/replication-features-create-select.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="replication-features-create-select">
</a>
19.5.1.7 Replication of CREATE TABLE ... SELECT Statements
</h4>
</div>
</div>
</div>
<a class="indexterm" name="idm46045135901088">
</a>
<a class="indexterm" name="idm46045135899632">
</a>
<p>
MySQL applies these rules when
<a class="link" href="create-table-select.html" title="15.1.20.4 CREATE TABLE ... SELECT Statement">
<code class="literal">
CREATE
TABLE ... SELECT
</code>
</a>
statements are replicated:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<a class="link" href="create-table-select.html" title="15.1.20.4 CREATE TABLE ... SELECT Statement">
<code class="literal">
CREATE
TABLE ... SELECT
</code>
</a>
always performs an implicit
commit (
<a class="xref" href="implicit-commit.html" title="15.3.3 Statements That Cause an Implicit Commit">
Section 15.3.3, “Statements That Cause an Implicit Commit”
</a>
).
</p>
</li>
<li class="listitem">
<p>
If the destination table does not exist, logging occurs as
follows. It does not matter whether
<code class="literal">
IF NOT
EXISTS
</code>
is present.
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
<code class="literal">
STATEMENT
</code>
or
<code class="literal">
MIXED
</code>
format: The statement is logged as written.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
ROW
</code>
format: The statement is logged
as a
<a class="link" href="create-table.html" title="15.1.20 CREATE TABLE Statement">
<code class="literal">
CREATE TABLE
</code>
</a>
statement followed by a series of insert-row events.
</p>
<p>
With storage engines that support atomic DDL, the
statement is logged as one transaction. For more
information, see
<a class="xref" href="atomic-ddl.html" title="15.1.1 Atomic Data Definition Statement Support">
Section 15.1.1, “Atomic Data Definition Statement Support”
</a>
.
</p>
</li>
</ul>
</div>
</li>
<li class="listitem">
<p>
If the
<a class="link" href="create-table-select.html" title="15.1.20.4 CREATE TABLE ... SELECT Statement">
<code class="literal">
CREATE
TABLE ... SELECT
</code>
</a>
statement fails, nothing is
logged. This includes the case that the destination table
exists and
<code class="literal">
IF NOT EXISTS
</code>
is not given.
</p>
</li>
<li class="listitem">
<p>
If the destination table exists and
<code class="literal">
IF NOT
EXISTS
</code>
is given, MySQL 8.4 ignores
the statement completely; nothing is inserted or logged.
</p>
</li>
</ul>
</div>
<p>
MySQL 8.4 does not allow a
<a class="link" href="create-table-select.html" title="15.1.20.4 CREATE TABLE ... SELECT Statement">
<code class="literal">
CREATE
TABLE ... SELECT
</code>
</a>
statement to make any changes in
tables other than the table that is created by the statement.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/comments.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h2 class="title">
<a name="comments">
</a>
11.7 Comments
</h2>
</div>
</div>
</div>
<a class="indexterm" name="idm46045218248560">
</a>
<a class="indexterm" name="idm46045218247488">
</a>
<p>
MySQL Server supports three comment styles:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
From a
<code class="literal">
#
</code>
character to the end of the line.
</p>
</li>
<li class="listitem">
<p>
From a
<code class="literal">
--
</code>
sequence to the end of the
line. In MySQL, the
<code class="literal">
--
</code>
(double-dash)
comment style requires the second dash to be followed by at
least one whitespace or control character (such as a space,
tab, newline, and so on). This syntax differs slightly from
standard SQL comment syntax, as discussed in
<a class="xref" href="ansi-diff-comments.html" title="1.7.2.4 '--' as the Start of a Comment">
Section 1.7.2.4, “'--' as the Start of a Comment”
</a>
.
</p>
</li>
<li class="listitem">
<p>
From a
<code class="literal">
/*
</code>
sequence to the following
<code class="literal">
*/
</code>
sequence, as in the C programming
language. This syntax enables a comment to extend over
multiple lines because the beginning and closing sequences
need not be on the same line.
</p>
</li>
</ul>
</div>
<p>
The following example demonstrates all three comment styles:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa74548659"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token number">1</span><span class="token operator">+</span><span class="token number">1</span><span class="token punctuation">;</span> <span class="token comment" spellcheck="true"># This comment continues to the end of line</span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token number">1</span><span class="token operator">+</span><span class="token number">1</span><span class="token punctuation">;</span> <span class="token comment" spellcheck="true">-- This comment continues to the end of line</span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token number">1</span> <span class="token comment" spellcheck="true">/* this is an in-line comment */</span> <span class="token operator">+</span> <span class="token number">1</span><span class="token punctuation">;</span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token number">1</span><span class="token operator">+</span>
<span class="token comment" spellcheck="true">/*
this is a
multiple-line comment
*/</span>
<span class="token number">1</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
Nested comments are not supported, and are deprecated; expect them
to be removed in a future MySQL release. (Under some conditions,
nested comments might be permitted, but usually are not, and users
should avoid them.)
</p>
<p>
MySQL Server supports certain variants of C-style comments. These
enable you to write code that includes MySQL extensions, but is
still portable, by using comments of the following form:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-sql"><div class="docs-select-all right" id="sa93741027"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token comment" spellcheck="true">/*! <em class="replaceable">MySQL-specific code</em> */</span></code></pre>
</div>
<p>
In this case, MySQL Server parses and executes the code within the
comment as it would any other SQL statement, but other SQL servers
should ignore the extensions. For example, MySQL Server recognizes
the
<code class="literal">
STRAIGHT_JOIN
</code>
keyword in the following
statement, but other servers should not:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-sql"><div class="docs-select-all right" id="sa479381"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">SELECT</span> <span class="token comment" spellcheck="true">/*! STRAIGHT_JOIN */</span> col1 <span class="token keyword">FROM</span> table1<span class="token punctuation">,</span>table2 <span class="token keyword">WHERE</span> <span class="token punctuation">.</span><span class="token punctuation">.</span><span class="token punctuation">.</span></code></pre>
</div>
<p>
If you add a version number after the
<code class="literal">
!
</code>
character, the syntax within the comment is executed only if the
MySQL version is greater than or equal to the specified version
number. The
<code class="literal">
KEY_BLOCK_SIZE
</code>
keyword in the
following comment is executed only by servers from MySQL 5.1.10 or
higher:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-sql"><div class="docs-select-all right" id="sa65295402"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">CREATE</span> <span class="token keyword">TABLE</span> t1<span class="token punctuation">(</span>a <span class="token datatype">INT</span><span class="token punctuation">,</span> <span class="token keyword">KEY</span> <span class="token punctuation">(</span>a<span class="token punctuation">)</span><span class="token punctuation">)</span> <span class="token comment" spellcheck="true">/*!50110 KEY_BLOCK_SIZE=1024 */</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
The version number uses the format
<em class="replaceable">
<code>
Mmmrr
</code>
</em>
, where
<em class="replaceable">
<code>
M
</code>
</em>
is a major version,
<em class="replaceable">
<code>
mm
</code>
</em>
is a two-digit minor version, and
<em class="replaceable">
<code>
rr
</code>
</em>
is a two-digit release number. For
example: In a statement to be run only by a MySQL server version
8.4.3 or later, use
<code class="literal">
80403
</code>
in the comment.
</p>
<p>
In MySQL 8.4, the version number can also optionally
be comprised of six digits in
<em class="replaceable">
<code>
MMmmrr
</code>
</em>
format, where
<em class="replaceable">
<code>
MM
</code>
</em>
is a two-digit major
version, and
<em class="replaceable">
<code>
mm
</code>
</em>
and
<em class="replaceable">
<code>
rr
</code>
</em>
are the two-digit minor version and
two-digit release numbers, respectively.
</p>
<p>
The version number should be followed by at least one whitespace
character (or the end of the comment). If the comment begins with
six digits followed by whitespace, this is interpreted as a
six-digit version number. Otherwise, if it begins with at least
five digits, these are interpreted as a five-digit version number
(and any remaining characters ignored for this purpose); if it
begins with fewer than five digits, the comment is handled as a
normal MySQL comment.
</p>
<p>
The comment syntax just described applies to how the
<a class="link" href="mysqld.html" title="6.3.1 mysqld — The MySQL Server">
<span class="command">
<strong>
mysqld
</strong>
</span>
</a>
server parses SQL statements. The
<a class="link" href="mysql.html" title="6.5.1 mysql — The MySQL Command-Line Client">
<span class="command">
<strong>
mysql
</strong>
</span>
</a>
client program also performs some parsing
of statements before sending them to the server. (It does this to
determine statement boundaries within a multiple-statement input
line.) For information about differences between the server and
<a class="link" href="mysql.html" title="6.5.1 mysql — The MySQL Command-Line Client">
<span class="command">
<strong>
mysql
</strong>
</span>
</a>
client parsers, see
<a class="xref" href="mysql-tips.html" title="6.5.1.6 mysql Client Tips">
Section 6.5.1.6, “mysql Client Tips”
</a>
.
</p>
<p>
Comments in
<code class="literal">
/*!12345 ... */
</code>
format are not
stored on the server. If this format is used to comment stored
programs, the comments are not retained in the program body.
</p>
<p>
Another variant of C-style comment syntax is used to specify
optimizer hints. Hint comments include a
<code class="literal">
+
</code>
character following the
<code class="literal">
/*
</code>
comment opening
sequence. Example:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-sql"><div class="docs-select-all right" id="sa25263082"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">SELECT</span> <span class="token comment" spellcheck="true">/*+ BKA(t1) */</span> <span class="token keyword">FROM</span> <span class="token punctuation">.</span><span class="token punctuation">.</span><span class="token punctuation">.</span> <span class="token punctuation">;</span></code></pre>
</div>
<p>
For more information, see
<a class="xref" href="optimizer-hints.html" title="10.9.3 Optimizer Hints">
Section 10.9.3, “Optimizer Hints”
</a>
.
</p>
<p>
The use of short-form
<a class="link" href="mysql.html" title="6.5.1 mysql — The MySQL Command-Line Client">
<span class="command">
<strong>
mysql
</strong>
</span>
</a>
commands such as
<code class="literal">
\C
</code>
within multiple-line
<code class="literal">
/* ...
*/
</code>
comments is not supported. Short-form commands do
work within single-line
<code class="literal">
/*! ... */
</code>
version
comments, as do
<code class="literal">
/*+ ... */
</code>
optimizer-hint
comments, which are stored in object definitions. If there is a
concern that optimizer-hint comments may be stored in object
definitions so that dump files when reloaded with
<code class="literal">
mysql
</code>
would result in execution of such
commands, either invoke
<a class="link" href="mysql.html" title="6.5.1 mysql — The MySQL Command-Line Client">
<span class="command">
<strong>
mysql
</strong>
</span>
</a>
with the
<a class="link" href="mysql-command-options.html#option_mysql_binary-mode">
<code class="option">
--binary-mode
</code>
</a>
option or use a reload
client other than
<a class="link" href="mysql.html" title="6.5.1 mysql — The MySQL Command-Line Client">
<span class="command">
<strong>
mysql
</strong>
</span>
</a>
.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/clone-plugin.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="clone-plugin">
</a>
7.6.7 The Clone Plugin
</h3>
</div>
</div>
</div>
<div class="toc">
<dl class="toc">
<dt>
<span class="section">
<a href="clone-plugin-installation.html">
7.6.7.1 Installing the Clone Plugin
</a>
</span>
</dt>
<dt>
<span class="section">
<a href="clone-plugin-local.html">
7.6.7.2 Cloning Data Locally
</a>
</span>
</dt>
<dt>
<span class="section">
<a href="clone-plugin-remote.html">
7.6.7.3 Cloning Remote Data
</a>
</span>
</dt>
<dt>
<span class="section">
<a href="clone-plugin-concurrent-ddl.html">
7.6.7.4 Cloning and Concurrent DDL
</a>
</span>
</dt>
<dt>
<span class="section">
<a href="clone-plugin-encrypted-data.html">
7.6.7.5 Cloning Encrypted Data
</a>
</span>
</dt>
<dt>
<span class="section">
<a href="clone-plugin-compressed-data.html">
7.6.7.6 Cloning Compressed Data
</a>
</span>
</dt>
<dt>
<span class="section">
<a href="clone-plugin-replication.html">
7.6.7.7 Cloning for Replication
</a>
</span>
</dt>
<dt>
<span class="section">
<a href="clone-plugin-directories.html">
7.6.7.8 Directories and Files Created During a Cloning Operation
</a>
</span>
</dt>
<dt>
<span class="section">
<a href="clone-plugin-failure-handling.html">
7.6.7.9 Remote Cloning Operation Failure Handling
</a>
</span>
</dt>
<dt>
<span class="section">
<a href="clone-plugin-monitoring.html">
7.6.7.10 Monitoring Cloning Operations
</a>
</span>
</dt>
<dt>
<span class="section">
<a href="clone-plugin-stop.html">
7.6.7.11 Stopping a Cloning Operation
</a>
</span>
</dt>
<dt>
<span class="section">
<a href="clone-plugin-option-variable-reference.html">
7.6.7.12 Clone System Variable Reference
</a>
</span>
</dt>
<dt>
<span class="section">
<a href="clone-plugin-options-variables.html">
7.6.7.13 Clone System Variables
</a>
</span>
</dt>
<dt>
<span class="section">
<a href="clone-plugin-limitations.html">
7.6.7.14 Clone Plugin Limitations
</a>
</span>
</dt>
</dl>
</div>
<a class="indexterm" name="idm46045255743680">
</a>
<a class="indexterm" name="idm46045255742608">
</a>
<a class="indexterm" name="idm46045255741536">
</a>
<p>
The clone plugin permits cloning data locally or from a remote
MySQL server instance. Cloned data is a physical snapshot of data
stored in
<code class="literal">
InnoDB
</code>
that includes schemas, tables,
tablespaces, and data dictionary metadata. The cloned data
comprises a fully functional data directory, which permits using
the clone plugin for MySQL server provisioning.
</p>
<div class="figure">
<a name="clone-plugin-local-diagram">
</a>
<p class="title">
<b>
Figure 7.1 Local Cloning Operation
</b>
</p>
<div class="figure-contents">
<div class="mediaobject">
<img alt="The CLONE LOCAL statement clones the data directory on a local MySQL Server instance to another local directory, which is referred to as the clone directory." src="images/clone-local.png" style="width: 100%; max-width: 307px;"/>
</div>
</div>
</div>
<br class="figure-break"/>
<p>
A local cloning operation clones data from the MySQL server
instance where the cloning operation is initiated to a directory
on the same server or node where MySQL server instance runs.
</p>
<div class="figure">
<a name="clone-plugin-remote-diagram">
</a>
<p class="title">
<b>
Figure 7.2 Remote Cloning Operation
</b>
</p>
<div class="figure-contents">
<div class="mediaobject">
<img alt="The CLONE INSTANCE statement issued from the local recipient MySQL Server instance clones the data directory from the remote donor MySQL server instance to the data directory on the local recipient MySQL Server instance." src="images/clone-remote.png" style="width: 100%; max-width: 307px;"/>
</div>
</div>
</div>
<br class="figure-break"/>
<p>
A remote cloning operation involves a local MySQL server instance
(the
<span class="quote">
“
<span class="quote">
recipient
</span>
”
</span>
) where the cloning operation is
initiated, and a remote MySQL server instance (the
<span class="quote">
“
<span class="quote">
donor
</span>
”
</span>
) where the source data is located. When a
remote cloning operation is initiated on the recipient, cloned
data is transferred over the network from the donor to the
recipient. By default, a remote cloning operation removes existing
user-created data (schemas, tables, tablespaces) and binary logs
from the recipient data directory before cloning data from the
donor. Optionally, you can clone data to a different directory on
the recipient to avoid removing data from the current recipient
data directory.
</p>
<p>
There is no difference with respect to data that is cloned by a
local cloning operation as compared to a remote cloning operation.
Both operations clone the same set of data.
</p>
<p>
The clone plugin supports replication. In addition to cloning
data, a cloning operation extracts and transfers replication
coordinates from the donor and applies them on the recipient,
which enables using the clone plugin for provisioning Group
Replication members and replicas. Using the clone plugin for
provisioning is considerably faster and more efficient than
replicating a large number of transactions (see
<a class="xref" href="clone-plugin-replication.html" title="7.6.7.7 Cloning for Replication">
Section 7.6.7.7, “Cloning for Replication”
</a>
). Group Replication
members can also be configured to use the clone plugin as an
alternative method of recovery, so that members automatically
choose the most efficient way to retrieve group data from seed
members. For more information, see
<a class="xref" href="group-replication-cloning.html" title="20.5.4.2 Cloning for Distributed Recovery">
Section 20.5.4.2, “Cloning for Distributed Recovery”
</a>
.
</p>
<p>
The clone plugin supports cloning of encrypted and page-compressed
data. See
<a class="xref" href="clone-plugin-encrypted-data.html" title="7.6.7.5 Cloning Encrypted Data">
Section 7.6.7.5, “Cloning Encrypted Data”
</a>
, and
<a class="xref" href="clone-plugin-compressed-data.html" title="7.6.7.6 Cloning Compressed Data">
Section 7.6.7.6, “Cloning Compressed Data”
</a>
.
</p>
<p>
The clone plugin must be installed before you can use it. For
installation instructions, see
<a class="xref" href="clone-plugin-installation.html" title="7.6.7.1 Installing the Clone Plugin">
Section 7.6.7.1, “Installing the Clone Plugin”
</a>
. For cloning
instructions, see
<a class="xref" href="clone-plugin-local.html" title="7.6.7.2 Cloning Data Locally">
Section 7.6.7.2, “Cloning Data Locally”
</a>
, and
<a class="xref" href="clone-plugin-remote.html" title="7.6.7.3 Cloning Remote Data">
Section 7.6.7.3, “Cloning Remote Data”
</a>
.
</p>
<p>
Performance Schema tables and instrumentation are provided for
monitoring cloning operations. See
<a class="xref" href="clone-plugin-monitoring.html" title="7.6.7.10 Monitoring Cloning Operations">
Section 7.6.7.10, “Monitoring Cloning Operations”
</a>
.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/macos-installation-prefpane.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="macos-installation-prefpane">
</a>
2.4.4 Installing and Using the MySQL Preference Pane
</h3>
</div>
</div>
</div>
<p>
The MySQL Installation Package includes a MySQL preference pane
that enables you to start, stop, and control automated startup
during boot of your MySQL installation.
</p>
<p>
This preference pane is installed by default, and is listed under
your system's
<span class="emphasis">
<em>
System Preferences
</em>
</span>
window.
</p>
<div class="figure">
<a name="mac-installer-preference-pane-location-initial">
</a>
<p class="title">
<b>
Figure 2.8 MySQL Preference Pane: Location
</b>
</p>
<div class="figure-contents">
<div class="mediaobject">
<img alt='Shows "MySQL" typed into the macOS System Preferences search box, and a highlighted "MySQL" icon in the bottom left.' src="images/mac-installer-preference-pane-location.png" style="width: 100%; max-width: 668px;"/>
</div>
</div>
</div>
<br class="figure-break"/>
<p>
The MySQL preference pane is installed with the same DMG file that
installs MySQL Server. Typically it is installed with MySQL Server
but it can be installed by itself too.
</p>
<p>
To install the MySQL preference pane:
</p>
<div class="orderedlist">
<ol class="orderedlist" type="1">
<li class="listitem">
<p>
Go through the process of installing the MySQL server, as
described in the documentation at
<a class="xref" href="macos-installation-pkg.html" title="2.4.2 Installing MySQL on macOS Using Native Packages">
Section 2.4.2, “Installing MySQL on macOS Using Native Packages”
</a>
.
</p>
</li>
<li class="listitem">
<p>
Click
<span class="guibutton">
Customize
</span>
at the
<span class="guilabel">
Installation Type
</span>
step. The "Preference
Pane" option is listed there and enabled by default; make sure
it is not deselected. The other options, such as MySQL Server,
can be selected or deselected.
</p>
<div class="figure">
<a name="mac-installer-installation-customize-pane">
</a>
<p class="title">
<b>
Figure 2.9 MySQL Package Installer Wizard: Customize
</b>
</p>
<div class="figure-contents">
<div class="mediaobject">
<img alt="Customize shows three package name options: MySQL Server, MySQL Test, Preference Pane, and Launchd Support. All three options are checked." src="images/mac-installer-installation-type-customize.png" style="width: 100%; max-width: 688px;"/>
</div>
</div>
</div>
<br class="figure-break"/>
</li>
<li class="listitem">
<p>
Complete the installation process.
</p>
</li>
</ol>
</div>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Note
</div>
<p>
The MySQL preference pane only starts and stops MySQL
installation installed from the MySQL package installation that
have been installed in the default location.
</p>
</div>
<p>
Once the MySQL preference pane has been installed, you can control
your MySQL server instance using this preference pane.
</p>
<p>
The
<span class="guilabel">
Instances
</span>
page includes an option to
start or stop MySQL, and
<span class="guibutton">
Initialize
Database
</span>
recreates the
<code class="filename">
data/
</code>
directory.
<span class="guibutton">
Uninstall
</span>
uninstalls MySQL
Server and optionally the MySQL preference panel and launchd
information.
</p>
<div class="figure">
<a name="mac-installer-preference-pane-instances-instances">
</a>
<p class="title">
<b>
Figure 2.10 MySQL Preference Pane: Instances
</b>
</p>
<div class="figure-contents">
<div class="mediaobject">
<img alt='The left side shows a list of MySQL instances separated by "Active Instance", "Installed Instances", and "Data Directories" sections. The right side shows a "Stop MySQL Server" button, a check box titled "Start MySQL when your computer starts up", and "Initialize Database" and "Uninstall" buttons.' src="images/mac-installer-preference-pane-instances.png" style="width: 100%; max-width: 780px;"/>
</div>
</div>
</div>
<br class="figure-break"/>
<p>
The
<span class="guilabel">
Configuration
</span>
page shows MySQL Server
options including the path to the MySQL configuration file.
</p>
<div class="figure">
<a name="mac-installer-preference-pane-configuration">
</a>
<p class="title">
<b>
Figure 2.11 MySQL Preference Pane: Configuration
</b>
</p>
<div class="figure-contents">
<div class="mediaobject">
<img alt="Content is described in the surrounding text." src="images/mac-installer-preference-pane-configuration.png" style="width: 100%; max-width: 780px;"/>
</div>
</div>
</div>
<br class="figure-break"/>
<p>
The MySQL Preference Pane shows the current status of the MySQL
server, showing
<span class="guilabel">
stopped
</span>
(in red) if the
server is not running and
<span class="guilabel">
running
</span>
(in green)
if the server has already been started. The preference pane also
shows the current setting for whether the MySQL server has been
set to start automatically.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-functions.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h2 class="title">
<a name="performance-schema-functions">
</a>
14.21 Performance Schema Functions
</h2>
</div>
</div>
</div>
<a class="indexterm" name="idm46045191704160">
</a>
<a class="indexterm" name="idm46045191702672">
</a>
<p>
MySQL includes built-in SQL functions that format or retrieve
Performance Schema data, and that may be used as equivalents for
the corresponding
<code class="literal">
sys
</code>
schema stored functions.
The built-in functions can be invoked in any schema and require no
qualifier, unlike the
<code class="literal">
sys
</code>
functions, which
require either a
<code class="literal">
sys.
</code>
schema qualifier or that
<code class="literal">
sys
</code>
be the current schema.
</p>
<div class="table">
<a name="idm46045191698064">
</a>
<p class="title">
<b>
Table 14.31 Performance Schema Functions
</b>
</p>
<div class="table-contents">
<table frame="box" rules="all" summary="A reference that lists Performance Schema functions.">
<colgroup>
<col style="width: 28%"/>
<col style="width: 71%"/>
</colgroup>
<thead>
<tr>
<th>
Name
</th>
<th>
Description
</th>
</tr>
</thead>
<tbody>
<tr>
<td>
<a class="link" href="performance-schema-functions.html#function_format-bytes">
<code class="literal">
FORMAT_BYTES()
</code>
</a>
</td>
<td>
Convert byte count to value with units
</td>
</tr>
<tr>
<td>
<a class="link" href="performance-schema-functions.html#function_format-pico-time">
<code class="literal">
FORMAT_PICO_TIME()
</code>
</a>
</td>
<td>
Convert time in picoseconds to value with units
</td>
</tr>
<tr>
<td>
<a class="link" href="performance-schema-functions.html#function_ps-current-thread-id">
<code class="literal">
PS_CURRENT_THREAD_ID()
</code>
</a>
</td>
<td>
Performance Schema thread ID for current thread
</td>
</tr>
<tr>
<td>
<a class="link" href="performance-schema-functions.html#function_ps-thread-id">
<code class="literal">
PS_THREAD_ID()
</code>
</a>
</td>
<td>
Performance Schema thread ID for given thread
</td>
</tr>
</tbody>
</table>
</div>
</div>
<br class="table-break"/>
<p>
The built-in functions supersede the corresponding
<code class="literal">
sys
</code>
functions, which are deprecated; expect
them to be removed in a future version of MySQL. Applications that
use the
<code class="literal">
sys
</code>
functions should be adjusted to use
the built-in functions instead, keeping in mind some minor
differences between the
<code class="literal">
sys
</code>
functions and the
built-in functions. For details about these differences, see the
function descriptions in this section.
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<a name="function_format-bytes">
</a>
<p>
<a class="link" href="performance-schema-functions.html#function_format-bytes">
<code class="literal">
FORMAT_BYTES(
<em class="replaceable">
<code>
count
</code>
</em>
)
</code>
</a>
</p>
<a class="indexterm" name="idm46045191671424">
</a>
<p>
Given a numeric byte count, converts it to human-readable
format and returns a string consisting of a value and a units
indicator. The string contains the number of bytes rounded to
2 decimal places and a minimum of 3 significant digits.
Numbers less than 1024 bytes are represented as whole numbers
and are not rounded. Returns
<code class="literal">
NULL
</code>
if
<em class="replaceable">
<code>
count
</code>
</em>
is
<code class="literal">
NULL
</code>
.
</p>
<p>
The units indicator depends on the size of the byte-count
argument as shown in the following table.
</p>
<div class="informaltable">
<table summary="Units indicators used by FORMAT_BYTES() function.">
<colgroup>
<col style="width: 30%"/>
<col style="width: 25%"/>
<col style="width: 45%"/>
</colgroup>
<thead>
<tr>
<th scope="col">
Argument Value
</th>
<th scope="col">
Result Units
</th>
<th scope="col">
Result Units Indicator
</th>
</tr>
</thead>
<tbody>
<tr>
<th scope="row">
Up to 1023
</th>
<td>
bytes
</td>
<td>
bytes
</td>
</tr>
<tr>
<th scope="row">
Up to 1024
<sup>
2
</sup>
− 1
</th>
<td>
kibibytes
</td>
<td>
KiB
</td>
</tr>
<tr>
<th scope="row">
Up to 1024
<sup>
3
</sup>
− 1
</th>
<td>
mebibytes
</td>
<td>
MiB
</td>
</tr>
<tr>
<th scope="row">
Up to 1024
<sup>
4
</sup>
− 1
</th>
<td>
gibibytes
</td>
<td>
GiB
</td>
</tr>
<tr>
<th scope="row">
Up to 1024
<sup>
5
</sup>
− 1
</th>
<td>
tebibytes
</td>
<td>
TiB
</td>
</tr>
<tr>
<th scope="row">
Up to 1024
<sup>
6
</sup>
− 1
</th>
<td>
pebibytes
</td>
<td>
PiB
</td>
</tr>
<tr>
<th scope="row">
1024
<sup>
6
</sup>
and up
</th>
<td>
exbibytes
</td>
<td>
EiB
</td>
</tr>
</tbody>
</table>
</div>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa82214424"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> FORMAT_BYTES<span class="token punctuation">(</span><span class="token number">512</span><span class="token punctuation">)</span><span class="token punctuation">,</span> FORMAT_BYTES<span class="token punctuation">(</span><span class="token number">18446644073709551615</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> FORMAT_BYTES(512) <span class="token punctuation">|</span> FORMAT_BYTES(18446644073709551615) <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> 512 bytes <span class="token punctuation">|</span> 16.00 EiB <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span></code></pre>
</div>
<p>
<a class="link" href="performance-schema-functions.html#function_format-bytes">
<code class="literal">
FORMAT_BYTES()
</code>
</a>
may be used
instead of the
<code class="literal">
sys
</code>
schema
<a class="link" href="sys-format-bytes.html" title="30.4.5.3 The format_bytes() Function">
<code class="literal">
format_bytes()
</code>
</a>
function, keeping
in mind this difference:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
<a class="link" href="performance-schema-functions.html#function_format-bytes">
<code class="literal">
FORMAT_BYTES()
</code>
</a>
uses the
<code class="literal">
EiB
</code>
units indicator.
<a class="link" href="sys-format-bytes.html" title="30.4.5.3 The format_bytes() Function">
<code class="literal">
sys.format_bytes()
</code>
</a>
does not.
</p>
</li>
</ul>
</div>
</li>
<li class="listitem">
<a name="function_format-pico-time">
</a>
<p>
<a class="link" href="performance-schema-functions.html#function_format-pico-time">
<code class="literal">
FORMAT_PICO_TIME(
<em class="replaceable">
<code>
time_val
</code>
</em>
)
</code>
</a>
</p>
<a class="indexterm" name="idm46045191617248">
</a>
<p>
Given a numeric Performance Schema latency or wait time in
picoseconds, converts it to human-readable format and returns
a string consisting of a value and a units indicator. The
string contains the decimal time rounded to 2 decimal places
and a minimum of 3 significant digits. Times under 1
nanosecond are represented as whole numbers and are not
rounded.
</p>
<p>
If
<em class="replaceable">
<code>
time_val
</code>
</em>
is
<code class="literal">
NULL
</code>
, this function returns
<code class="literal">
NULL
</code>
.
</p>
<p>
The units indicator depends on the size of the time-value
argument as shown in the following table.
</p>
<div class="informaltable">
<table summary="Units indicators used by FORMAT_PICO_TIME() function.">
<colgroup>
<col style="width: 30%"/>
<col style="width: 25%"/>
<col style="width: 45%"/>
</colgroup>
<thead>
<tr>
<th scope="col">
Argument Value
</th>
<th scope="col">
Result Units
</th>
<th scope="col">
Result Units Indicator
</th>
</tr>
</thead>
<tbody>
<tr>
<th scope="row">
Up to 10
<sup>
3
</sup>
− 1
</th>
<td>
picoseconds
</td>
<td>
ps
</td>
</tr>
<tr>
<th scope="row">
Up to 10
<sup>
6
</sup>
− 1
</th>
<td>
nanoseconds
</td>
<td>
ns
</td>
</tr>
<tr>
<th scope="row">
Up to 10
<sup>
9
</sup>
− 1
</th>
<td>
microseconds
</td>
<td>
us
</td>
</tr>
<tr>
<th scope="row">
Up to 10
<sup>
12
</sup>
− 1
</th>
<td>
milliseconds
</td>
<td>
ms
</td>
</tr>
<tr>
<th scope="row">
Up to 60×10
<sup>
12
</sup>
− 1
</th>
<td>
seconds
</td>
<td>
s
</td>
</tr>
<tr>
<th scope="row">
Up to 3.6×10
<sup>
15
</sup>
− 1
</th>
<td>
minutes
</td>
<td>
min
</td>
</tr>
<tr>
<th scope="row">
Up to 8.64×10
<sup>
16
</sup>
− 1
</th>
<td>
hours
</td>
<td>
h
</td>
</tr>
<tr>
<th scope="row">
8.64×10
<sup>
16
</sup>
and up
</th>
<td>
days
</td>
<td>
d
</td>
</tr>
</tbody>
</table>
</div>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa63395209"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> FORMAT_PICO_TIME<span class="token punctuation">(</span><span class="token number">3501</span><span class="token punctuation">)</span><span class="token punctuation">,</span> FORMAT_PICO_TIME<span class="token punctuation">(</span><span class="token number">188732396662000</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> FORMAT_PICO_TIME(3501) <span class="token punctuation">|</span> FORMAT_PICO_TIME(188732396662000) <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> 3.50 ns <span class="token punctuation">|</span> 3.15 min <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span></code></pre>
</div>
<p>
<a class="link" href="performance-schema-functions.html#function_format-pico-time">
<code class="literal">
FORMAT_PICO_TIME()
</code>
</a>
may be used
instead of the
<code class="literal">
sys
</code>
schema
<a class="link" href="sys-format-time.html" title="30.4.5.6 The format_time() Function">
<code class="literal">
format_time()
</code>
</a>
function, keeping
in mind these differences:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
To indicate minutes,
<a class="link" href="sys-format-time.html" title="30.4.5.6 The format_time() Function">
<code class="literal">
sys.format_time()
</code>
</a>
uses the
<code class="literal">
m
</code>
units indicator, whereas
<a class="link" href="performance-schema-functions.html#function_format-pico-time">
<code class="literal">
FORMAT_PICO_TIME()
</code>
</a>
uses
<code class="literal">
min
</code>
.
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="sys-format-time.html" title="30.4.5.6 The format_time() Function">
<code class="literal">
sys.format_time()
</code>
</a>
uses the
<code class="literal">
w
</code>
(weeks) units indicator.
<a class="link" href="performance-schema-functions.html#function_format-pico-time">
<code class="literal">
FORMAT_PICO_TIME()
</code>
</a>
does
not.
</p>
</li>
</ul>
</div>
</li>
<li class="listitem">
<a name="function_ps-current-thread-id">
</a>
<p>
<a class="link" href="performance-schema-functions.html#function_ps-current-thread-id">
<code class="literal">
PS_CURRENT_THREAD_ID()
</code>
</a>
</p>
<a class="indexterm" name="idm46045191554160">
</a>
<p>
Returns a
<code class="literal">
BIGINT UNSIGNED
</code>
value
representing the Performance Schema thread ID assigned to the
current connection.
</p>
<p>
The thread ID return value is a value of the type given in the
<code class="literal">
THREAD_ID
</code>
column of Performance Schema
tables.
</p>
<p>
Performance Schema configuration affects
<a class="link" href="performance-schema-functions.html#function_ps-current-thread-id">
<code class="literal">
PS_CURRENT_THREAD_ID()
</code>
</a>
the same
way as for
<a class="link" href="performance-schema-functions.html#function_ps-thread-id">
<code class="literal">
PS_THREAD_ID()
</code>
</a>
. For
details, see the description of that function.
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa88746901"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> PS_CURRENT_THREAD_ID<span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> PS_CURRENT_THREAD_ID() <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> 52 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> PS_THREAD_ID<span class="token punctuation">(</span><span class="token function">CONNECTION_ID</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> PS_THREAD_ID(CONNECTION_ID()) <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> 52 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span></code></pre>
</div>
<p>
<a class="link" href="performance-schema-functions.html#function_ps-current-thread-id">
<code class="literal">
PS_CURRENT_THREAD_ID()
</code>
</a>
may be
used as a shortcut for invoking the
<code class="literal">
sys
</code>
schema
<a class="link" href="sys-ps-thread-id.html" title="30.4.5.15 The ps_thread_id() Function">
<code class="literal">
ps_thread_id()
</code>
</a>
function
with an argument of
<code class="literal">
NULL
</code>
or
<a class="link" href="information-functions.html#function_connection-id">
<code class="literal">
CONNECTION_ID()
</code>
</a>
.
</p>
</li>
<li class="listitem">
<a name="function_ps-thread-id">
</a>
<p>
<a class="link" href="performance-schema-functions.html#function_ps-thread-id">
<code class="literal">
PS_THREAD_ID(
<em class="replaceable">
<code>
connection_id
</code>
</em>
)
</code>
</a>
</p>
<a class="indexterm" name="idm46045191532640">
</a>
<p>
Given a connection ID, returns a
<code class="literal">
BIGINT
UNSIGNED
</code>
value representing the Performance Schema
thread ID assigned to the connection ID, or
<code class="literal">
NULL
</code>
if no thread ID exists for the
connection ID. The latter can occur for threads that are not
instrumented, or if
<em class="replaceable">
<code>
connection_id
</code>
</em>
is
<code class="literal">
NULL
</code>
.
</p>
<p>
The connection ID argument is a value of the type given in the
<code class="literal">
PROCESSLIST_ID
</code>
column of the Performance
Schema
<a class="link" href="performance-schema-threads-table.html" title="29.12.22.8 The threads Table">
<code class="literal">
threads
</code>
</a>
table or the
<code class="literal">
Id
</code>
column of
<a class="link" href="show-processlist.html" title="15.7.7.31 SHOW PROCESSLIST Statement">
<code class="literal">
SHOW
PROCESSLIST
</code>
</a>
output.
</p>
<p>
The thread ID return value is a value of the type given in the
<code class="literal">
THREAD_ID
</code>
column of Performance Schema
tables.
</p>
<p>
Performance Schema configuration affects
<a class="link" href="performance-schema-functions.html#function_ps-thread-id">
<code class="literal">
PS_THREAD_ID()
</code>
</a>
operation as
follows. (These remarks also apply to
<a class="link" href="performance-schema-functions.html#function_ps-current-thread-id">
<code class="literal">
PS_CURRENT_THREAD_ID()
</code>
</a>
.)
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
Disabling the
<code class="literal">
thread_instrumentation
</code>
consumer disables statistics from being collected and
aggregated at the thread level, but has no effect on
<a class="link" href="performance-schema-functions.html#function_ps-thread-id">
<code class="literal">
PS_THREAD_ID()
</code>
</a>
.
</p>
</li>
<li class="listitem">
<p>
If
<a class="link" href="performance-schema-system-variables.html#sysvar_performance_schema_max_thread_instances">
<code class="literal">
performance_schema_max_thread_instances
</code>
</a>
is not 0, the Performance Schema allocates memory for
thread statistics and assigns an internal ID to each
thread for which instance memory is available. If there
are threads for which instance memory is not available,
<a class="link" href="performance-schema-functions.html#function_ps-thread-id">
<code class="literal">
PS_THREAD_ID()
</code>
</a>
returns
<code class="literal">
NULL
</code>
; in this case,
<a class="link" href="performance-schema-status-variables.html#statvar_Performance_schema_thread_instances_lost">
<code class="literal">
Performance_schema_thread_instances_lost
</code>
</a>
is nonzero.
</p>
</li>
<li class="listitem">
<p>
If
<a class="link" href="performance-schema-system-variables.html#sysvar_performance_schema_max_thread_instances">
<code class="literal">
performance_schema_max_thread_instances
</code>
</a>
is 0, the Performance Schema allocates no thread memory
and
<a class="link" href="performance-schema-functions.html#function_ps-thread-id">
<code class="literal">
PS_THREAD_ID()
</code>
</a>
returns
<code class="literal">
NULL
</code>
.
</p>
</li>
<li class="listitem">
<p>
If the Performance Schema itself is disabled,
<a class="link" href="performance-schema-functions.html#function_ps-thread-id">
<code class="literal">
PS_THREAD_ID()
</code>
</a>
produces an
error.
</p>
</li>
</ul>
</div>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa32280947"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> PS_THREAD_ID<span class="token punctuation">(</span><span class="token number">6</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> PS_THREAD_ID(6) <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> 45 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span></code></pre>
</div>
<p>
<a class="link" href="performance-schema-functions.html#function_ps-thread-id">
<code class="literal">
PS_THREAD_ID()
</code>
</a>
may be used
instead of the
<code class="literal">
sys
</code>
schema
<a class="link" href="sys-ps-thread-id.html" title="30.4.5.15 The ps_thread_id() Function">
<code class="literal">
ps_thread_id()
</code>
</a>
function, keeping
in mind this difference:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
With an argument of
<code class="literal">
NULL
</code>
,
<a class="link" href="sys-ps-thread-id.html" title="30.4.5.15 The ps_thread_id() Function">
<code class="literal">
sys.ps_thread_id()
</code>
</a>
returns
the thread ID for the current connection, whereas
<a class="link" href="performance-schema-functions.html#function_ps-thread-id">
<code class="literal">
PS_THREAD_ID()
</code>
</a>
returns
<code class="literal">
NULL
</code>
. To obtain the current connection
thread ID, use
<a class="link" href="performance-schema-functions.html#function_ps-current-thread-id">
<code class="literal">
PS_CURRENT_THREAD_ID()
</code>
</a>
instead.
</p>
</li>
</ul>
</div>
</li>
</ul>
</div>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/apis-perl.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h2 class="title">
<a name="apis-perl">
</a>
31.9 MySQL Perl API
</h2>
</div>
</div>
</div>
<a class="indexterm" name="idm46045060342208">
</a>
<a class="indexterm" name="idm46045060340752">
</a>
<a class="indexterm" name="idm46045060339680">
</a>
<a class="indexterm" name="idm46045060338608">
</a>
<p>
The Perl
<code class="literal">
DBI
</code>
module provides a generic interface
for database access. You can write a DBI script that works with many
different database engines without change. To use DBI with MySQL,
install the following:
</p>
<div class="orderedlist">
<ol class="orderedlist" type="1">
<li class="listitem">
<p>
The
<code class="literal">
DBI
</code>
module.
</p>
</li>
<li class="listitem">
<p>
The
<code class="literal">
DBD::mysql
</code>
module. This is the DataBase
Driver (DBD) module for Perl.
</p>
</li>
<li class="listitem">
<p>
Optionally, the DBD module for any other type of database server
you want to access.
</p>
</li>
</ol>
</div>
<p>
Perl DBI is the recommended Perl interface. It replaces an older
interface called
<code class="literal">
mysqlperl
</code>
, which should be
considered obsolete.
</p>
<p>
These sections contain information about using Perl with MySQL and
writing MySQL applications in Perl:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
For installation instructions for Perl DBI support, see
<a class="xref" href="perl-support.html" title="2.10 Perl Installation Notes">
Section 2.10, “Perl Installation Notes”
</a>
.
</p>
</li>
<li class="listitem">
<p>
For an example of reading options from option files, see
<a class="xref" href="multiple-server-clients.html" title="7.8.4 Using Client Programs in a Multiple-Server Environment">
Section 7.8.4, “Using Client Programs in a Multiple-Server Environment”
</a>
.
</p>
</li>
<li class="listitem">
<p>
For secure coding tips, see
<a class="xref" href="security-guidelines.html" title="8.1.1 Security Guidelines">
Section 8.1.1, “Security Guidelines”
</a>
.
</p>
</li>
<li class="listitem">
<p>
For debugging tips, see
<a class="xref" href="using-gdb-on-mysqld.html" title="7.9.1.4 Debugging mysqld under gdb">
Section 7.9.1.4, “Debugging mysqld under gdb”
</a>
.
</p>
</li>
<li class="listitem">
<p>
For some Perl-specific environment variables, see
<a class="xref" href="environment-variables.html" title="6.9 Environment Variables">
Section 6.9, “Environment Variables”
</a>
.
</p>
</li>
<li class="listitem">
<p>
For considerations for running on macOS, see
<a class="xref" href="macos-installation.html" title="2.4 Installing MySQL on macOS">
Section 2.4, “Installing MySQL on macOS”
</a>
.
</p>
</li>
<li class="listitem">
<p>
For ways to quote string literals, see
<a class="xref" href="string-literals.html" title="11.1.1 String Literals">
Section 11.1.1, “String Literals”
</a>
.
</p>
</li>
</ul>
</div>
<p>
DBI information is available at the command line, online, or in
printed form:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
Once you have the
<code class="literal">
DBI
</code>
and
<code class="literal">
DBD::mysql
</code>
modules installed, you can get
information about them at the command line with the
<code class="literal">
perldoc
</code>
command:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-terminal"><div class="docs-select-all right" id="sa77570387"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal"><span class="token prompt">$> </span><span class="token command">perldoc</span> DBI
<span class="token prompt">$> </span><span class="token command">perldoc</span> DBI<span class="token punctuation">:</span><span class="token punctuation">:</span>FAQ
<span class="token prompt">$> </span><span class="token command">perldoc</span> DBD<span class="token punctuation">:</span><span class="token punctuation">:</span>mysql</code></pre>
</div>
<p>
You can also use
<code class="literal">
pod2man
</code>
,
<code class="literal">
pod2html
</code>
, and so on to translate this
information into other formats.
</p>
</li>
<li class="listitem">
<p>
For online information about Perl DBI, visit the DBI website,
<a class="ulink" href="http://dbi.perl.org/" target="_blank">
http://dbi.perl.org/
</a>
. That site hosts a general
DBI mailing list.
</p>
</li>
<li class="listitem">
<p>
For printed information, the official DBI book is
<em class="citetitle">
Programming the Perl DBI
</em>
(Alligator
Descartes and Tim Bunce, O'Reilly & Associates, 2000).
Information about the book is available at the DBI website,
<a class="ulink" href="http://dbi.perl.org/" target="_blank">
http://dbi.perl.org/
</a>
.
</p>
</li>
</ul>
</div>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/group-replication-cloning.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="group-replication-cloning">
</a>
20.5.4.2 Cloning for Distributed Recovery
</h4>
</div>
</div>
</div>
<p>
If you want to use remote cloning operations for distributed
recovery in a group, you must set up existing members and
joining members beforehand to support this function. If you do
not want to use this function in a group, do not set it up, in
which case Group Replication only uses state transfer from the
binary log.
</p>
<p>
To use cloning, at least one existing group member and the
joining member must be set up beforehand to support remote
cloning operations. As a minimum, you must install the clone
plugin on the donor and joining member, grant the
<a class="link" href="privileges-provided.html#priv_backup-admin">
<code class="literal">
BACKUP_ADMIN
</code>
</a>
permission to the
replication user for distributed recovery, and set the
<a class="link" href="group-replication-system-variables.html#sysvar_group_replication_clone_threshold">
<code class="literal">
group_replication_clone_threshold
</code>
</a>
system variable to an appropriate level. To ensure the maximum
availability of donors, it is advisable to set up all current
and future group members to support remote cloning operations.
</p>
<p>
Be aware that a remote cloning operation removes user-created
tablespaces and data from the joining member before transferring
the data from the donor. If the operation is stopped while in
progress, the joining member might be left with partial data or
no data. This can be repaired by retrying the remote cloning
operation, which Group Replication does automatically.
</p>
<div class="section">
<div class="titlepage">
<div>
<div>
<h5 class="title">
<a name="group-replication-cloning-prerequisites">
</a>
20.5.4.2.1 Prerequisites for Cloning
</h5>
</div>
</div>
</div>
<p>
For full instructions to set up and configure the clone
plugin, see
<a class="xref" href="clone-plugin.html" title="7.6.7 The Clone Plugin">
Section 7.6.7, “The Clone Plugin”
</a>
. Detailed
prerequisites for a remote cloning operation are covered in
<a class="xref" href="clone-plugin-remote.html" title="7.6.7.3 Cloning Remote Data">
Section 7.6.7.3, “Cloning Remote Data”
</a>
. For Group Replication,
note the following key points and differences:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
The donor (an existing group member) and the recipient
(the joining member) must have the clone plugin installed
and active. For instructions to do this, see
<a class="xref" href="clone-plugin-installation.html" title="7.6.7.1 Installing the Clone Plugin">
Section 7.6.7.1, “Installing the Clone Plugin”
</a>
.
</p>
</li>
<li class="listitem">
<p>
The donor and the recipient must run on the same operating
system, and must use the same MySQL Server release series.
Cloning is therefore not suitable for groups where members
run different minor MySQL Server versions, such as MySQL
8.0 and 8.4.
</p>
</li>
<li class="listitem">
<p>
The donor and the recipient must have the Group
Replication plugin installed and active, and any other
plugins that are active on the donor (such as a keyring
plugin) must also be active on the recipient.
</p>
</li>
<li class="listitem">
<p>
If distributed recovery is configured to use SSL
(
<a class="link" href="group-replication-system-variables.html#sysvar_group_replication_recovery_use_ssl">
<code class="literal">
group_replication_recovery_use_ssl=ON
</code>
</a>
),
Group Replication applies this setting for remote cloning
operations. Group Replication automatically configures the
settings for the clone SSL options
(
<a class="link" href="clone-plugin-options-variables.html#sysvar_clone_ssl_ca">
<code class="literal">
clone_ssl_ca
</code>
</a>
,
<a class="link" href="clone-plugin-options-variables.html#sysvar_clone_ssl_cert">
<code class="literal">
clone_ssl_cert
</code>
</a>
, and
<a class="link" href="clone-plugin-options-variables.html#sysvar_clone_ssl_key">
<code class="literal">
clone_ssl_key
</code>
</a>
) to match
your settings for the corresponding Group Replication
distributed recovery options
(
<a class="link" href="group-replication-system-variables.html#sysvar_group_replication_recovery_ssl_ca">
<code class="literal">
group_replication_recovery_ssl_ca
</code>
</a>
,
<a class="link" href="group-replication-system-variables.html#sysvar_group_replication_recovery_ssl_cert">
<code class="literal">
group_replication_recovery_ssl_cert
</code>
</a>
,
and
<a class="link" href="group-replication-system-variables.html#sysvar_group_replication_recovery_ssl_key">
<code class="literal">
group_replication_recovery_ssl_key
</code>
</a>
).
</p>
</li>
<li class="listitem">
<p>
You do not need to set up a list of valid donors in the
<a class="link" href="clone-plugin-options-variables.html#sysvar_clone_valid_donor_list">
<code class="literal">
clone_valid_donor_list
</code>
</a>
system variable for the purpose of joining a replication
group. Group Replication configures this setting
automatically for you after it selects a donor from the
existing group members. Note that remote cloning
operations use the server's SQL protocol hostname and
port.
</p>
</li>
<li class="listitem">
<p>
The clone plugin has a number of system variables to
manage the network load and performance impact of the
remote cloning operation. Group Replication does not
configure these settings, so you can review them and set
them if you want to, or allow them to default. Note that
when a remote cloning operation is used for distributed
recovery, the clone plugin's
<a class="link" href="clone-plugin-options-variables.html#sysvar_clone_enable_compression">
<code class="literal">
clone_enable_compression
</code>
</a>
setting applies to the operation, rather than the Group
Replication compression setting.
</p>
</li>
<li class="listitem">
<p>
To invoke the remote cloning operation on the recipient,
Group Replication uses the internal
<code class="literal">
mysql.session
</code>
user, which already has
the
<a class="link" href="privileges-provided.html#priv_clone-admin">
<code class="literal">
CLONE_ADMIN
</code>
</a>
privilege,
so you do not need to set this up.
</p>
</li>
<li class="listitem">
<p>
As the clone user on the donor for the remote cloning
operation, Group Replication uses the replication user
that you set up for distributed recovery (which is covered
in
<a class="xref" href="group-replication-user-credentials.html" title="20.2.1.3 User Credentials For Distributed Recovery">
Section 20.2.1.3, “User Credentials For Distributed Recovery”
</a>
).
You must therefore give the
<a class="link" href="privileges-provided.html#priv_backup-admin">
<code class="literal">
BACKUP_ADMIN
</code>
</a>
privilege to
this replication user on all group members that support
cloning. Also give the privilege to the replication user
on joining members when you are configuring them for Group
Replication, because they can act as donors after they
join the group. The same replication user is used for
distributed recovery on every group member. To give this
privilege to the replication user on existing members, you
can issue this statement on each group member individually
with binary logging disabled, or on one group member with
binary logging enabled:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-sql"><div class="docs-select-all right" id="sa17474695"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">GRANT</span> BACKUP_ADMIN <span class="token keyword">ON</span> <span class="token operator">*</span><span class="token punctuation">.</span><span class="token operator">*</span> <span class="token keyword">TO</span> <em class="replaceable">rpl_user</em>@<span class="token string">'%'</span><span class="token punctuation">;</span></code></pre>
</div>
</li>
<li class="listitem">
<p>
If you use
<a class="link" href="start-group-replication.html" title="15.4.3.1 START GROUP_REPLICATION Statement">
<code class="literal">
START
GROUP_REPLICATION
</code>
</a>
to specify the replication
user credentials on a server that previously supplied the
user credentials using
<a class="link" href="change-replication-source-to.html" title="15.4.2.2 CHANGE REPLICATION SOURCE TO Statement">
<code class="literal">
CHANGE
REPLICATION SOURCE TO
</code>
</a>
, ensure that you remove
the user credentials from the replication metadata
repositories before any remote cloning operations take
place. Also ensure that
<a class="link" href="group-replication-system-variables.html#sysvar_group_replication_start_on_boot">
<code class="literal">
group_replication_start_on_boot=OFF
</code>
</a>
is set on the joining member. For instructions, see
<a class="xref" href="group-replication-distributed-recovery-securing.html" title="20.6.3 Securing Distributed Recovery Connections">
Section 20.6.3, “Securing Distributed Recovery Connections”
</a>
.
If you do not unset the user credentials, they are
transferred to the joining member during remote cloning
operations. The
<code class="literal">
group_replication_recovery
</code>
channel
could then be inadvertently started with the stored
credentials, on either the original member or members that
were cloned from it. An automatic start of Group
Replication on server boot (including after a remote
cloning operation) would use the stored user credentials,
and they would also be used if an operator did not specify
the distributed recovery credentials on a
<a class="link" href="start-group-replication.html" title="15.4.3.1 START GROUP_REPLICATION Statement">
<code class="literal">
START GROUP_REPLICATION
</code>
</a>
statement.
</p>
</li>
</ul>
</div>
</div>
<div class="section">
<div class="titlepage">
<div>
<div>
<h5 class="title">
<a name="group-replication-cloning-threshold">
</a>
20.5.4.2.2 Threshold for Cloning
</h5>
</div>
</div>
</div>
<p>
When group members have been set up to support cloning, the
<a class="link" href="group-replication-system-variables.html#sysvar_group_replication_clone_threshold">
<code class="literal">
group_replication_clone_threshold
</code>
</a>
system variable specifies a threshold, expressed as a number
of transactions, for the use of a remote cloning operation in
distributed recovery. If the gap between the transactions on
the donor and the transactions on the joining member is larger
than this number, a remote cloning operation is used for state
transfer to the joining member when this is technically
possible. Group Replication calculates whether the threshold
has been exceeded based on the
<a class="link" href="replication-options-gtids.html#sysvar_gtid_executed">
<code class="literal">
gtid_executed
</code>
</a>
sets of the
existing group members. Using a remote cloning operation in
the event of a large transaction gap lets you add new members
to the group without transferring the group's data to the
server manually beforehand, and also enables a member that is
very out of date to catch up more efficiently.
</p>
<p>
The default setting for the
<a class="link" href="group-replication-system-variables.html#sysvar_group_replication_clone_threshold">
<code class="literal">
group_replication_clone_threshold
</code>
</a>
Group Replication system variable is extremely high (the
maximum permitted sequence number for a transaction in a
GTID), so it effectively deactivates cloning wherever state
transfer from the binary log is possible. To enable Group
Replication to select a remote cloning operation for state
transfer where this is more appropriate, set the system
variable to specify a number of transactions as the
transaction gap above which you want cloning to take place.
</p>
<div class="warning" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Warning
</div>
<p>
Do not use a low setting for
<a class="link" href="group-replication-system-variables.html#sysvar_group_replication_clone_threshold">
<code class="literal">
group_replication_clone_threshold
</code>
</a>
in an active group. If a number of transactions above the
threshold takes place in the group while the remote cloning
operation is in progress, the joining member triggers a
remote cloning operation again after restarting, and could
continue this indefinitely. To avoid this situation, ensure
that you set the threshold to a number higher than the
number of transactions that you would expect to occur in the
group during the time taken for the remote cloning
operation.
</p>
</div>
<p>
Group Replication attempts to execute a remote cloning
operation regardless of your threshold when state transfer
from a donor's binary log is impossible, for example because
the transactions needed by the joining member are not
available in the binary log on any existing group member.
Group Replication identifies this based on the
<a class="link" href="replication-options-gtids.html#sysvar_gtid_purged">
<code class="literal">
gtid_purged
</code>
</a>
sets of the
existing group members. You cannot use the
<a class="link" href="group-replication-system-variables.html#sysvar_group_replication_clone_threshold">
<code class="literal">
group_replication_clone_threshold
</code>
</a>
system variable to deactivate cloning when the required
transactions are not available in any member's binary log
files, because in that situation cloning is the only
alternative to transferring data to the joining member
manually.
</p>
</div>
<div class="section">
<div class="titlepage">
<div>
<div>
<h5 class="title">
<a name="group-replication-cloning-operations">
</a>
20.5.4.2.3 Cloning Operations
</h5>
</div>
</div>
</div>
<p>
When group members and joining members are set up for cloning,
Group Replication manages remote cloning operations for you. A
remote cloning operation might take some time to complete,
depending on the size of the data. See
<a class="xref" href="clone-plugin-monitoring.html" title="7.6.7.10 Monitoring Cloning Operations">
Section 7.6.7.10, “Monitoring Cloning Operations”
</a>
for information on
monitoring the process.
</p>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Note
</div>
<p>
When state transfer is complete, Group Replication restarts
the joining member to complete the process. If
<a class="link" href="group-replication-system-variables.html#sysvar_group_replication_start_on_boot">
<code class="literal">
group_replication_start_on_boot=OFF
</code>
</a>
is set on the joining member, for example because you
specify the replication user credentials on the
<a class="link" href="start-group-replication.html" title="15.4.3.1 START GROUP_REPLICATION Statement">
<code class="literal">
START GROUP_REPLICATION
</code>
</a>
statement, you must issue
<a class="link" href="start-group-replication.html" title="15.4.3.1 START GROUP_REPLICATION Statement">
<code class="literal">
START
GROUP_REPLICATION
</code>
</a>
manually again following this
restart. If
<a class="link" href="group-replication-system-variables.html#sysvar_group_replication_start_on_boot">
<code class="literal">
group_replication_start_on_boot=ON
</code>
</a>
and other settings required to start Group Replication were
set in a configuration file or using a
<code class="literal">
SET
PERSIST
</code>
statement, you do not need to intervene
and the process continues automatically to bring the joining
member online.
</p>
</div>
<p>
A remote cloning operation clones settings that are persisted
in tables from the donor to the recipient, as well as the
data. Group Replication manages the settings that relate
specifically to Group Replication channels. Group Replication
member settings that are persisted in configuration files,
such as the group replication local address, are not cloned
and are not changed on the joining member. Group Replication
also preserves the channel settings that relate to the use of
SSL, so these are unique to the individual member.
</p>
<p>
If the replication user credentials used by the donor for the
<code class="literal">
group_replication_recovery
</code>
replication
channel have been stored in the replication metadata
repositories using a
<a class="link" href="change-replication-source-to.html" title="15.4.2.2 CHANGE REPLICATION SOURCE TO Statement">
<code class="literal">
CHANGE REPLICATION
SOURCE TO
</code>
</a>
statement, they are transferred to and
used by the joining member after cloning, and they must be
valid there. With stored credentials, all group members that
received state transfer by a remote cloning operation
therefore automatically receive the replication user and
password for distributed recovery. If you specify the
replication user credentials on the
<a class="link" href="start-group-replication.html" title="15.4.3.1 START GROUP_REPLICATION Statement">
<code class="literal">
START
GROUP_REPLICATION
</code>
</a>
statement, these are used to start
the remote cloning operation, but they are not transferred to
and used by the joining member after cloning. If you do not
want the credentials transferred to new joiners and recorded
there, ensure that you unset them before remote cloning
operations take place, as described in
<a class="xref" href="group-replication-distributed-recovery-securing.html" title="20.6.3 Securing Distributed Recovery Connections">
Section 20.6.3, “Securing Distributed Recovery Connections”
</a>
,
and use
<a class="link" href="start-group-replication.html" title="15.4.3.1 START GROUP_REPLICATION Statement">
<code class="literal">
START GROUP_REPLICATION
</code>
</a>
to supply them instead.
</p>
<p>
If a
<code class="literal">
PRIVILEGE_CHECKS_USER
</code>
account has been
used to help secure the replication appliers (see
<a class="xref" href="replication-privilege-checks-gr.html" title="19.3.3.2 Privilege Checks For Group Replication Channels">
Section 19.3.3.2, “Privilege Checks For Group Replication Channels”
</a>
), the
<code class="literal">
PRIVILEGE_CHECKS_USER
</code>
account and related
settings from the donor are cloned to the joining member. If
the joining member is set to start Group Replication on boot,
it automatically uses the account for privilege checks on the
appropriate replication channels.
</p>
</div>
<div class="section">
<div class="titlepage">
<div>
<div>
<h5 class="title">
<a name="group-replication-cloning-manual">
</a>
20.5.4.2.4 Cloning for Other Purposes
</h5>
</div>
</div>
</div>
<p>
Group Replication initiates and manages cloning operations for
distributed recovery. Group members that have been set up to
support cloning may also participate in cloning operations
that a user initiates manually. For example, you might want to
create a new server instance by cloning from a group member as
the donor, but you do not want the new server instance to join
the group immediately, or maybe not ever.
</p>
<p>
In all releases that support cloning, you can initiate a
cloning operation manually involving a group member on which
Group Replication is stopped. Note that because cloning
requires that the active plugins on a donor and recipient must
match, the Group Replication plugin must be installed and
active on the other server instance, even if you do not intend
that server instance to join a group. You can install the
plugin by issuing this statement:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-sql"><div class="docs-select-all right" id="sa96693190"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">INSTALL</span> <span class="token keyword">PLUGIN</span> <span class="token keyword">group_replication</span> <span class="token keyword">SONAME</span> <span class="token string">'group_replication.so'</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
You can initiate a cloning operation manually if the operation
involves a group member on which Group Replication is running,
provided that the cloning operation does not remove and
replace the data on the recipient. The statement to initiate
the cloning operation must therefore include the
<code class="literal">
DATA
DIRECTORY
</code>
clause if Group Replication is running.
</p>
</div>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-ndbinfo-logspaces.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="mysql-cluster-ndbinfo-logspaces">
</a>
25.6.17.44 The ndbinfo logspaces Table
</h4>
</div>
</div>
</div>
<a class="indexterm" name="idm46045088977200">
</a>
<p>
This table provides information about NDB Cluster log space
usage.
</p>
<p>
The
<code class="literal">
logspaces
</code>
table contains the following
columns:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<code class="literal">
node_id
</code>
</p>
<p>
The ID of this data node.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
log_type
</code>
</p>
<p>
Type of log; one of:
<code class="literal">
REDO
</code>
or
<code class="literal">
DD-UNDO
</code>
.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
node_id
</code>
</p>
<p>
The log ID; for Disk Data undo log files, this is the same
as the value shown in the
<code class="literal">
LOGFILE_GROUP_NUMBER
</code>
column of the
Information Schema
<a class="link" href="information-schema-files-table.html" title="28.3.15 The INFORMATION_SCHEMA FILES Table">
<code class="literal">
FILES
</code>
</a>
table,
as well as the value shown for the
<code class="literal">
log_id
</code>
column of the
<code class="literal">
ndbinfo
</code>
<a class="link" href="mysql-cluster-ndbinfo-logbuffers.html" title="25.6.17.43 The ndbinfo logbuffers Table">
<code class="literal">
logbuffers
</code>
</a>
table
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
log_part
</code>
</p>
<p>
The log part number.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
total
</code>
</p>
<p>
Total space available for this log.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
used
</code>
</p>
<p>
Space used by this log.
</p>
</li>
</ul>
</div>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-ndbinfo-cluster-locks.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="mysql-cluster-ndbinfo-cluster-locks">
</a>
25.6.17.7 The ndbinfo cluster_locks Table
</h4>
</div>
</div>
</div>
<a class="indexterm" name="idm46045090427296">
</a>
<p>
The
<code class="literal">
cluster_locks
</code>
table provides information
about current lock requests holding and waiting for locks on
<code class="literal">
NDB
</code>
tables in an NDB Cluster, and is intended
as a companion table to
<a class="link" href="mysql-cluster-ndbinfo-cluster-operations.html" title="25.6.17.8 The ndbinfo cluster_operations Table">
<code class="literal">
cluster_operations
</code>
</a>
.
Information obtain from the
<code class="literal">
cluster_locks
</code>
table may be useful in investigating stalls and deadlocks.
</p>
<p>
The
<code class="literal">
cluster_locks
</code>
table contains the
following columns:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<code class="literal">
node_id
</code>
</p>
<p>
ID of reporting node
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
block_instance
</code>
</p>
<p>
ID of reporting LDM instance
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
tableid
</code>
</p>
<p>
ID of table containing this row
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
fragmentid
</code>
</p>
<p>
ID of fragment containing locked row
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
rowid
</code>
</p>
<p>
ID of locked row
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
transid
</code>
</p>
<p>
Transaction ID
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
mode
</code>
</p>
<p>
Lock request mode
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
state
</code>
</p>
<p>
Lock state
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
detail
</code>
</p>
<p>
Whether this is first holding lock in row lock queue
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
op
</code>
</p>
<p>
Operation type
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
duration_millis
</code>
</p>
<p>
Milliseconds spent waiting or holding lock
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
lock_num
</code>
</p>
<p>
ID of lock object
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
waiting_for
</code>
</p>
<p>
Waiting for lock with this ID
</p>
</li>
</ul>
</div>
<h5>
<a name="idm46045090395440">
</a>
Notes
</h5>
<p>
The table ID (
<code class="literal">
tableid
</code>
column) is assigned
internally, and is the same as that used in other
<code class="literal">
ndbinfo
</code>
tables. It is also shown in the
output of
<a class="link" href="mysql-cluster-programs-ndb-show-tables.html" title="25.5.27 ndb_show_tables — Display List of NDB Tables">
<span class="command">
<strong>
ndb_show_tables
</strong>
</span>
</a>
.
</p>
<p>
The transaction ID (
<code class="literal">
transid
</code>
column) is the
identifier generated by the NDB API for the transaction
requesting or holding the current lock.
</p>
<p>
The
<code class="literal">
mode
</code>
column shows the lock mode; this is
always one of
<code class="literal">
S
</code>
(indicating a shared lock) or
<code class="literal">
X
</code>
(an exclusive lock). If a transaction holds
an exclusive lock on a given row, all other locks on that row
have the same transaction ID.
</p>
<p>
The
<code class="literal">
state
</code>
column shows the lock state. Its
value is always one of
<code class="literal">
H
</code>
(holding) or
<code class="literal">
W
</code>
(waiting). A waiting lock request waits for
a lock held by a different transaction.
</p>
<p>
When the
<code class="literal">
detail
</code>
column contains a
<code class="literal">
*
</code>
(asterisk character), this means that this
lock is the first holding lock in the affected row's lock
queue; otherwise, this column is empty. This information can be
used to help identify the unique entries in a list of lock
requests.
</p>
<p>
The
<code class="literal">
op
</code>
column shows the type of operation
requesting the lock. This is always one of the values
<code class="literal">
READ
</code>
,
<code class="literal">
INSERT
</code>
,
<code class="literal">
UPDATE
</code>
,
<code class="literal">
DELETE
</code>
,
<code class="literal">
SCAN
</code>
, or
<code class="literal">
REFRESH
</code>
.
</p>
<p>
The
<code class="literal">
duration_millis
</code>
column shows the number
of milliseconds for which this lock request has been waiting or
holding the lock. This is reset to 0 when a lock is granted for
a waiting request.
</p>
<p>
The lock ID (
<code class="literal">
lockid
</code>
column) is unique to this
node and block instance.
</p>
<p>
The lock state is shown in the
<code class="literal">
lock_state
</code>
column; if this is
<code class="literal">
W
</code>
, the lock is waiting to
be granted, and the
<code class="literal">
waiting_for
</code>
column shows
the lock ID of the lock object this request is waiting for.
Otherwise, the
<code class="literal">
waiting_for
</code>
column is empty.
<code class="literal">
waiting_for
</code>
can refer only to locks on the
same row, as identified by
<code class="literal">
node_id
</code>
,
<code class="literal">
block_instance
</code>
,
<code class="literal">
tableid
</code>
,
<code class="literal">
fragmentid
</code>
, and
<code class="literal">
rowid
</code>
.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/myisam-maintenance-schedule.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="myisam-maintenance-schedule">
</a>
9.6.5 Setting Up a MyISAM Table Maintenance Schedule
</h3>
</div>
</div>
</div>
<a class="indexterm" name="idm46045230456128">
</a>
<a class="indexterm" name="idm46045230454640">
</a>
<p>
It is a good idea to perform table checks on a regular basis
rather than waiting for problems to occur. One way to check and
repair
<code class="literal">
MyISAM
</code>
tables is with the
<a class="link" href="check-table.html" title="15.7.3.2 CHECK TABLE Statement">
<code class="literal">
CHECK TABLE
</code>
</a>
and
<a class="link" href="repair-table.html" title="15.7.3.5 REPAIR TABLE Statement">
<code class="literal">
REPAIR TABLE
</code>
</a>
statements. See
<a class="xref" href="table-maintenance-statements.html" title="15.7.3 Table Maintenance Statements">
Section 15.7.3, “Table Maintenance Statements”
</a>
.
</p>
<p>
Another way to check tables is to use
<a class="link" href="myisamchk.html" title="6.6.4 myisamchk — MyISAM Table-Maintenance Utility">
<span class="command">
<strong>
myisamchk
</strong>
</span>
</a>
. For maintenance purposes, you can
use
<a class="link" href="myisamchk.html" title="6.6.4 myisamchk — MyISAM Table-Maintenance Utility">
<span class="command">
<strong>
myisamchk -s
</strong>
</span>
</a>
. The
<code class="option">
-s
</code>
option (short for
<a class="link" href="myisamchk-general-options.html#option_myisamchk_silent">
<code class="option">
--silent
</code>
</a>
)
causes
<a class="link" href="myisamchk.html" title="6.6.4 myisamchk — MyISAM Table-Maintenance Utility">
<span class="command">
<strong>
myisamchk
</strong>
</span>
</a>
to run in silent mode,
printing messages only when errors occur.
</p>
<a class="indexterm" name="idm46045230443088">
</a>
<p>
It is also a good idea to enable automatic
<code class="literal">
MyISAM
</code>
table checking. For example, whenever
the machine has done a restart in the middle of an update, you
usually need to check each table that could have been affected
before it is used further. (These are
<span class="quote">
“
<span class="quote">
expected crashed
tables.
</span>
”
</span>
) To cause the server to check
<code class="literal">
MyISAM
</code>
tables automatically, start it with
the
<a class="link" href="server-system-variables.html#sysvar_myisam_recover_options">
<code class="literal">
myisam_recover_options
</code>
</a>
system variable set. See
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
.
</p>
<p>
You should also check your tables regularly during normal system
operation. For example, you can run a
<span class="command">
<strong>
cron
</strong>
</span>
job to check important tables once a week, using a line like
this in a
<code class="filename">
crontab
</code>
file:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-simple"><div class="docs-select-all right" id="sa28209721"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-simple">35 0 <span class="token operator">*</span> <span class="token operator">*</span> 0 <span class="token operator"></span><em class="replaceable"><span class="token operator">/</span>path<span class="token operator">/</span>to<span class="token operator">/</span>myisamchk</em> <span class="token operator">--</span>fast <span class="token operator">--</span>silent <span class="token operator"></span><em class="replaceable"><span class="token operator">/</span>path<span class="token operator">/</span>to<span class="token operator">/</span>datadir</em><span class="token operator">/</span><span class="token operator">*</span><span class="token operator">/</span><span class="token operator">*</span><span class="token punctuation">.</span>MYI</code></pre>
</div>
<p>
This prints out information about crashed tables so that you can
examine and repair them as necessary.
</p>
<p>
To start with, execute
<a class="link" href="myisamchk.html" title="6.6.4 myisamchk — MyISAM Table-Maintenance Utility">
<span class="command">
<strong>
myisamchk -s
</strong>
</span>
</a>
each
night on all tables that have been updated during the last 24
hours. As you see that problems occur infrequently, you can back
off the checking frequency to once a week or so.
</p>
<a class="indexterm" name="idm46045230431136">
</a>
<p>
Normally, MySQL tables need little maintenance. If you are
performing many updates to
<code class="literal">
MyISAM
</code>
tables with
dynamic-sized rows (tables with
<a class="link" href="char.html" title="13.3.2 The CHAR and VARCHAR Types">
<code class="literal">
VARCHAR
</code>
</a>
,
<a class="link" href="blob.html" title="13.3.4 The BLOB and TEXT Types">
<code class="literal">
BLOB
</code>
</a>
, or
<a class="link" href="blob.html" title="13.3.4 The BLOB and TEXT Types">
<code class="literal">
TEXT
</code>
</a>
columns) or have tables with
many deleted rows you may want to defragment/reclaim space from
the tables from time to time. You can do this by using
<a class="link" href="optimize-table.html" title="15.7.3.4 OPTIMIZE TABLE Statement">
<code class="literal">
OPTIMIZE TABLE
</code>
</a>
on the tables in
question. Alternatively, if you can stop the
<a class="link" href="mysqld.html" title="6.3.1 mysqld — The MySQL Server">
<span class="command">
<strong>
mysqld
</strong>
</span>
</a>
server for a while, change location
into the data directory and use this command while the server is
stopped:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-terminal"><div class="docs-select-all right" id="sa97580296"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal"><span class="token prompt">$> </span><span class="token command">myisamchk</span> <span class="token property">-r</span> <span class="token property">-s</span> <span class="token property">--sort-index</span> <span class="token constant">--myisam_sort_buffer_size</span><span class="token attr-value"><span class="token punctuation">=</span>16M</span> */*<span class="token punctuation">.</span>MYI</code></pre>
</div>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/faqs-information-schema.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h2 class="title">
<a name="faqs-information-schema">
</a>
A.7 MySQL 8.4 FAQ: INFORMATION_SCHEMA
</h2>
</div>
</div>
</div>
<div class="qandaset">
<a name="idm46045056154192">
</a>
<dl>
<dt>
A.7.1.
<a href="faqs-information-schema.html#faq-mysql-where-docs-information-schema">
Where can I find documentation for the MySQL
INFORMATION_SCHEMA database?
</a>
</dt>
<dt>
A.7.2.
<a href="faqs-information-schema.html#faq-mysql-where-forum-information-schema">
Is there a discussion forum for
INFORMATION_SCHEMA?
</a>
</dt>
<dt>
A.7.3.
<a href="faqs-information-schema.html#faq-mysql-where-ansi-information-schema">
Where can I find the ANSI SQL 2003 specification for
INFORMATION_SCHEMA?
</a>
</dt>
<dt>
A.7.4.
<a href="faqs-information-schema.html#faq-mysql-compare-oracle-data-dir-info-schema">
What is the difference between the Oracle Data Dictionary and
MySQL INFORMATION_SCHEMA?
</a>
</dt>
<dt>
A.7.5.
<a href="faqs-information-schema.html#faq-mysql-can-modify-information-schema">
Can I add to or otherwise modify the tables found in the
INFORMATION_SCHEMA database?
</a>
</dt>
</dl>
<table border="0" style="width: 100%;">
<colgroup>
<col align="left" width="1%"/>
<col/>
</colgroup>
<tbody>
<tr class="question">
<td align="left" valign="top">
<a name="faq-mysql-where-docs-information-schema">
</a>
<a name="idm46045056153440">
</a>
<p>
<b>
A.7.1.
</b>
</p>
</td>
<td align="left" valign="top">
<p>
Where can I find documentation for the MySQL
<code class="literal">
INFORMATION_SCHEMA
</code>
database?
</p>
</td>
</tr>
<tr class="answer">
<td align="left" valign="top">
</td>
<td align="left" valign="top">
<p>
See
<a class="xref" href="information-schema.html" title="Chapter 28 INFORMATION_SCHEMA Tables">
Chapter 28,
<i>
INFORMATION_SCHEMA Tables
</i>
</a>
.
</p>
<p>
You may also find the
<a class="ulink" href="https://forums.mysql.com/list.php?20" target="_blank">
MySQL User Forums
</a>
to be helpful.
</p>
</td>
</tr>
<tr class="question">
<td align="left" valign="top">
<a name="faq-mysql-where-forum-information-schema">
</a>
<a name="idm46045056148880">
</a>
<p>
<b>
A.7.2.
</b>
</p>
</td>
<td align="left" valign="top">
<p>
Is there a discussion forum for
<code class="literal">
INFORMATION_SCHEMA
</code>
?
</p>
</td>
</tr>
<tr class="answer">
<td align="left" valign="top">
</td>
<td align="left" valign="top">
<p>
See the
<a class="ulink" href="https://forums.mysql.com/list.php?20" target="_blank">
MySQL User
Forums
</a>
.
</p>
</td>
</tr>
<tr class="question">
<td align="left" valign="top">
<a name="faq-mysql-where-ansi-information-schema">
</a>
<a name="idm46045056145408">
</a>
<p>
<b>
A.7.3.
</b>
</p>
</td>
<td align="left" valign="top">
<p>
Where can I find the ANSI SQL 2003 specification for
<code class="literal">
INFORMATION_SCHEMA
</code>
?
</p>
</td>
</tr>
<tr class="answer">
<td align="left" valign="top">
</td>
<td align="left" valign="top">
<p>
Unfortunately, the official specifications are not freely
available. (ANSI makes them available for purchase.) However,
there are books available, such as
<em class="citetitle">
SQL-99 Complete,
Really
</em>
by Peter Gulutzan and Trudy Pelzer, that
provide a comprehensive overview of the standard, including
<code class="literal">
INFORMATION_SCHEMA
</code>
.
</p>
</td>
</tr>
<tr class="question">
<td align="left" valign="top">
<a name="faq-mysql-compare-oracle-data-dir-info-schema">
</a>
<a name="idm46045056141168">
</a>
<p>
<b>
A.7.4.
</b>
</p>
</td>
<td align="left" valign="top">
<p>
What is the difference between the Oracle Data Dictionary and
MySQL
<code class="literal">
INFORMATION_SCHEMA
</code>
?
</p>
</td>
</tr>
<tr class="answer">
<td align="left" valign="top">
</td>
<td align="left" valign="top">
<p>
Both Oracle and MySQL provide metadata in tables. However,
Oracle and MySQL use different table names and column names. The
MySQL implementation is more similar to those found in DB2 and
SQL Server, which also support
<code class="literal">
INFORMATION_SCHEMA
</code>
as defined in the SQL
standard.
</p>
</td>
</tr>
<tr class="question">
<td align="left" valign="top">
<a name="faq-mysql-can-modify-information-schema">
</a>
<a name="idm46045056137488">
</a>
<p>
<b>
A.7.5.
</b>
</p>
</td>
<td align="left" valign="top">
<p>
Can I add to or otherwise modify the tables found in the
<code class="literal">
INFORMATION_SCHEMA
</code>
database?
</p>
</td>
</tr>
<tr class="answer">
<td align="left" valign="top">
</td>
<td align="left" valign="top">
<p>
No. Since applications may rely on a certain standard structure,
this should not be modified. For this reason,
<span class="emphasis">
<em>
we
cannot support bugs or other issues which result from modifying
<code class="literal">
INFORMATION_SCHEMA
</code>
tables or data
</em>
</span>
.
</p>
</td>
</tr>
</tbody>
</table>
</div>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/multiple-windows-services.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="multiple-windows-services">
</a>
7.8.2.2 Starting Multiple MySQL Instances as Windows Services
</h4>
</div>
</div>
</div>
<p>
On Windows, a MySQL server can run as a Windows service. The
procedures for installing, controlling, and removing a single
MySQL service are described in
<a class="xref" href="windows-start-service.html" title="2.3.3.8 Starting MySQL as a Windows Service">
Section 2.3.3.8, “Starting MySQL as a Windows Service”
</a>
.
</p>
<p>
To set up multiple MySQL services, you must make sure that each
instance uses a different service name in addition to the other
parameters that must be unique per instance.
</p>
<p>
For the following instructions, suppose that you want to run the
<a class="link" href="mysqld.html" title="6.3.1 mysqld — The MySQL Server">
<span class="command">
<strong>
mysqld
</strong>
</span>
</a>
server from two different versions of
MySQL that are installed at
<code class="filename">
C:\mysql-5.7.9
</code>
and
<code class="filename">
C:\mysql-8.4.3
</code>
,
respectively. (This might be the case if you are running 5.7.9
as your production server, but also want to conduct tests using
8.4.3.)
</p>
<p>
To install MySQL as a Windows service, use the
<code class="option">
--install
</code>
or
<code class="option">
--install-manual
</code>
option. For information about these options, see
<a class="xref" href="windows-start-service.html" title="2.3.3.8 Starting MySQL as a Windows Service">
Section 2.3.3.8, “Starting MySQL as a Windows Service”
</a>
.
</p>
<p>
Based on the preceding information, you have several ways to set
up multiple services. The following instructions describe some
examples. Before trying any of them, shut down and remove any
existing MySQL services.
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<span class="bold">
<strong>
Approach 1:
</strong>
</span>
Specify the
options for all services in one of the standard option
files. To do this, use a different service name for each
server. Suppose that you want to run the 5.7.9
<a class="link" href="mysqld.html" title="6.3.1 mysqld — The MySQL Server">
<span class="command">
<strong>
mysqld
</strong>
</span>
</a>
using the service name of
<code class="literal">
mysqld1
</code>
and the 8.4.3
<a class="link" href="mysqld.html" title="6.3.1 mysqld — The MySQL Server">
<span class="command">
<strong>
mysqld
</strong>
</span>
</a>
using the service name
<code class="literal">
mysqld2
</code>
. In this case, you can use the
<code class="literal">
[mysqld1]
</code>
group for 5.7.9 and the
<code class="literal">
[mysqld2]
</code>
group for 8.4.3.
For example, you can set up
<code class="filename">
C:\my.cnf
</code>
like this:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-ini"><div class="docs-select-all right" id="sa12762797"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-ini"><span class="token comment" spellcheck="true"># options for mysqld1 service</span>
<span class="token selector">[mysqld1]</span>
<span class="token constant">basedir</span> <span class="token attr-value"><span class="token punctuation">=</span> C:/mysql-5.7.9</span>
<span class="token constant">port</span> <span class="token attr-value"><span class="token punctuation">=</span> 3307</span>
<span class="token constant">enable-named-pipe</span>
<span class="token constant">socket</span> <span class="token attr-value"><span class="token punctuation">=</span> mypipe1</span>
<span class="token comment" spellcheck="true"># options for mysqld2 service</span>
<span class="token selector">[mysqld2]</span>
<span class="token constant">basedir</span> <span class="token attr-value"><span class="token punctuation">=</span> C:/mysql-8.4.3</span>
<span class="token constant">port</span> <span class="token attr-value"><span class="token punctuation">=</span> 3308</span>
<span class="token constant">enable-named-pipe</span>
<span class="token constant">socket</span> <span class="token attr-value"><span class="token punctuation">=</span> mypipe2</span></code></pre>
</div>
<p>
Install the services as follows, using the full server path
names to ensure that Windows registers the correct
executable program for each service:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-terminal"><div class="docs-select-all right" id="sa95456109"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal"><span class="token prompt">C:\></span><span class="token command"> C:\mysql-5.7.9\bin\mysqld</span> <span class="token property">--install</span> mysqld1
<span class="token prompt">C:\></span><span class="token command"> C:\mysql-8.4.3\bin\mysqld</span> <span class="token property">--install</span> mysqld2</code></pre>
</div>
<p>
To start the services, use the services manager, or
<span class="command">
<strong>
NET START
</strong>
</span>
or
<span class="command">
<strong>
SC START
</strong>
</span>
with the appropriate service names:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-terminal"><div class="docs-select-all right" id="sa75237884"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal"><span class="token prompt">C:\></span><span class="token command"> SC</span> START mysqld1
<span class="token prompt">C:\></span><span class="token command"> SC</span> START mysqld2</code></pre>
</div>
<p>
To stop the services, use the services manager, or use
<span class="command">
<strong>
NET STOP
</strong>
</span>
or
<span class="command">
<strong>
SC STOP
</strong>
</span>
with the appropriate service names:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-terminal"><div class="docs-select-all right" id="sa5456928"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal"><span class="token prompt">C:\></span><span class="token command"> SC</span> STOP mysqld1
<span class="token prompt">C:\></span><span class="token command"> SC</span> STOP mysqld2</code></pre>
</div>
</li>
<li class="listitem">
<p>
<span class="bold">
<strong>
Approach 2:
</strong>
</span>
Specify options
for each server in separate files and use
<a class="link" href="option-file-options.html#option_general_defaults-file">
<code class="option">
--defaults-file
</code>
</a>
when you
install the services to tell each server what file to use.
In this case, each file should list options using a
<code class="literal">
[mysqld]
</code>
group.
</p>
<p>
With this approach, to specify options for the 5.7.9
<a class="link" href="mysqld.html" title="6.3.1 mysqld — The MySQL Server">
<span class="command">
<strong>
mysqld
</strong>
</span>
</a>
, create a file
<code class="filename">
C:\my-opts1.cnf
</code>
that looks like this:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-ini"><div class="docs-select-all right" id="sa49440738"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-ini"><span class="token selector">[mysqld]</span>
<span class="token constant">basedir</span> <span class="token attr-value"><span class="token punctuation">=</span> C:/mysql-5.7.9</span>
<span class="token constant">port</span> <span class="token attr-value"><span class="token punctuation">=</span> 3307</span>
<span class="token constant">enable-named-pipe</span>
<span class="token constant">socket</span> <span class="token attr-value"><span class="token punctuation">=</span> mypipe1</span></code></pre>
</div>
<p>
For the 8.4.3
<a class="link" href="mysqld.html" title="6.3.1 mysqld — The MySQL Server">
<span class="command">
<strong>
mysqld
</strong>
</span>
</a>
, create
a file
<code class="filename">
C:\my-opts2.cnf
</code>
that looks like
this:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-ini"><div class="docs-select-all right" id="sa28760675"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-ini"><span class="token selector">[mysqld]</span>
<span class="token constant">basedir</span> <span class="token attr-value"><span class="token punctuation">=</span> C:/mysql-8.4.3</span>
<span class="token constant">port</span> <span class="token attr-value"><span class="token punctuation">=</span> 3308</span>
<span class="token constant">enable-named-pipe</span>
<span class="token constant">socket</span> <span class="token attr-value"><span class="token punctuation">=</span> mypipe2</span></code></pre>
</div>
<p>
Install the services as follows (enter each command on a
single line):
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-terminal"><div class="docs-select-all right" id="sa25832254"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal"><span class="token prompt">C:\></span><span class="token command"> C:\mysql-5.7.9\bin\mysqld</span> <span class="token property">--install</span> mysqld1
<span class="token constant">--defaults-file</span><span class="token attr-value"><span class="token punctuation">=</span>C:\my-opts1.cnf</span>
<span class="token prompt">C:\></span><span class="token command"> C:\mysql-8.4.3\bin\mysqld</span> <span class="token property">--install</span> mysqld2
<span class="token constant">--defaults-file</span><span class="token attr-value"><span class="token punctuation">=</span>C:\my-opts2.cnf</span></code></pre>
</div>
<p>
When you install a MySQL server as a service and use a
<a class="link" href="option-file-options.html#option_general_defaults-file">
<code class="option">
--defaults-file
</code>
</a>
option, the
service name must precede the option.
</p>
<p>
After installing the services, start and stop them the same
way as in the preceding example.
</p>
</li>
</ul>
</div>
<p>
To remove multiple services, use
<span class="command">
<strong>
SC DELETE
<em class="replaceable">
<code>
mysqld_service_name
</code>
</em>
</strong>
</span>
for
each one. Alternatively, use
<a class="link" href="mysqld.html" title="6.3.1 mysqld — The MySQL Server">
<span class="command">
<strong>
mysqld --remove
</strong>
</span>
</a>
for each one, specifying a service name following the
<a class="link" href="server-options.html#option_mysqld_remove">
<code class="option">
--remove
</code>
</a>
option. If the service
name is the default (
<code class="literal">
MySQL
</code>
), you can omit it
when using
<a class="link" href="mysqld.html" title="6.3.1 mysqld — The MySQL Server">
<span class="command">
<strong>
mysqld --remove
</strong>
</span>
</a>
.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/mysql-oci-marketplace-maintenance.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h2 class="title">
<a name="mysql-oci-marketplace-maintenance">
</a>
34.5 Maintenance
</h2>
</div>
</div>
</div>
<p>
This product is user-managed, meaning you are responsible for
upgrades and maintenance.
</p>
<div class="simplesect">
<div class="titlepage">
<div>
<div class="simple">
<h3 class="title">
<a name="mysql-oci-marketplace-maintenance-upgrading">
</a>
Upgrading MySQL
</h3>
</div>
</div>
</div>
<p>
The existing installation is RPM-based, to upgrade the MySQL
server, see
<a class="xref" href="upgrade-binary-package.html" title="3.7 Upgrading MySQL Binary or Package-based Installations on Unix/Linux">
Section 3.7, “Upgrading MySQL Binary or Package-based Installations on Unix/Linux”
</a>
.
</p>
<p>
You can use
<code class="filename">
scp
</code>
to copy the required RPM to
the OCI Compute Instance, or copy it from OCI Object Storage, if
you have configured access to it. File Storage is also an
option. For more information, see
<a class="ulink" href="https://docs.cloud.oracle.com/iaas/Content/File/Concepts/filestorageoverview.htm" target="_blank">
File
Storage and NFS
</a>
.
</p>
</div>
<div class="simplesect">
<div class="titlepage">
<div>
<div class="simple">
<h3 class="title">
<a name="mysql-oci-marketplace-maintenance-backuprestore">
</a>
Backup and Restore
</h3>
</div>
</div>
</div>
<p>
MySQL Enterprise Backup is the preferred backup and restore solution. For more
information, see
<a class="ulink" href="/doc/mysql-enterprise-backup/8.4/en/meb-backup-cloud.html" target="_top">
Backing Up to Cloud Storage
</a>
.
</p>
<p>
For information on MySQL Enterprise Backup, see
<a class="ulink" href="/doc/mysql-enterprise-backup/8.4/en/meb-getting-started.html" target="_top">
Getting Started with MySQL Enterprise Backup
</a>
.
</p>
<p>
For information on the default MySQL backup and restore, see
<a class="xref" href="backup-and-recovery.html" title="Chapter 9 Backup and Recovery">
Chapter 9,
<i>
Backup and Recovery
</i>
</a>
.
</p>
</div>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/server-configuration-defaults.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="server-configuration-defaults">
</a>
7.1.2 Server Configuration Defaults
</h3>
</div>
</div>
</div>
<p>
The MySQL server has many operating parameters, which you can
change at server startup using command-line options or
configuration files (option files). It is also possible to change
many parameters at runtime. For general instructions on setting
parameters at startup or runtime, see
<a class="xref" href="server-options.html" title="7.1.7 Server Command Options">
Section 7.1.7, “Server Command Options”
</a>
, and
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
.
</p>
<p>
On Windows, MySQL Installer interacts with the user and creates a
file named
<code class="filename">
my.ini
</code>
in the base installation
directory as the default option file.
</p>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Note
</div>
<p>
On Windows, the
<code class="filename">
.ini
</code>
or
<code class="filename">
.cnf
</code>
option file extension might not be
displayed.
</p>
</div>
<p>
After completing the installation process, you can edit the
default option file at any time to modify the parameters used by
the server. For example, to use a parameter setting in the file
that is commented with a
<code class="literal">
#
</code>
character at the
beginning of the line, remove the
<code class="literal">
#
</code>
, and modify
the parameter value if necessary. To disable a setting, either add
a
<code class="literal">
#
</code>
to the beginning of the line or remove it.
</p>
<p>
For non-Windows platforms, no default option file is created
during either the server installation or the data directory
initialization process. Create your option file by following the
instructions given in
<a class="xref" href="option-files.html" title="6.2.2.2 Using Option Files">
Section 6.2.2.2, “Using Option Files”
</a>
. Without an
option file, the server just starts with its default
settings—see
<a class="xref" href="server-configuration-defaults.html" title="7.1.2 Server Configuration Defaults">
Section 7.1.2, “Server Configuration Defaults”
</a>
on how to check those settings.
</p>
<p>
For additional information about option file format and syntax,
see
<a class="xref" href="option-files.html" title="6.2.2.2 Using Option Files">
Section 6.2.2.2, “Using Option Files”
</a>
.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/innodb-information-schema-transactions.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="innodb-information-schema-transactions">
</a>
17.15.2 InnoDB INFORMATION_SCHEMA Transaction and Locking Information
</h3>
</div>
</div>
</div>
<div class="toc">
<dl class="toc">
<dt>
<span class="section">
<a href="innodb-information-schema-examples.html">
17.15.2.1 Using InnoDB Transaction and Locking Information
</a>
</span>
</dt>
<dt>
<span class="section">
<a href="innodb-information-schema-understanding-innodb-locking.html">
17.15.2.2 InnoDB Lock and Lock-Wait Information
</a>
</span>
</dt>
<dt>
<span class="section">
<a href="innodb-information-schema-internal-data.html">
17.15.2.3 Persistence and Consistency of InnoDB Transaction and Locking
Information
</a>
</span>
</dt>
</dl>
</div>
<a class="indexterm" name="idm46045151244656">
</a>
<a class="indexterm" name="idm46045151243168">
</a>
<p>
One
<code class="literal">
INFORMATION_SCHEMA
</code>
table and two
Performance Schema tables enable you to monitor
<code class="literal">
InnoDB
</code>
transactions and diagnose potential
locking problems:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<a class="link" href="information-schema-innodb-trx-table.html" title="28.4.28 The INFORMATION_SCHEMA INNODB_TRX Table">
<code class="literal">
INNODB_TRX
</code>
</a>
: This
<code class="literal">
INFORMATION_SCHEMA
</code>
table provides
information about every transaction currently executing inside
<code class="literal">
InnoDB
</code>
, including the transaction state
(for example, whether it is running or waiting for a lock),
when the transaction started, and the particular SQL statement
the transaction is executing.
</p>
<a class="indexterm" name="idm46045151235824">
</a>
</li>
<li class="listitem">
<p>
<a class="link" href="performance-schema-data-locks-table.html" title="29.12.13.1 The data_locks Table">
<code class="literal">
data_locks
</code>
</a>
: This Performance
Schema table contains a row for each hold lock and each lock
request that is blocked waiting for a held lock to be
released:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
There is one row for each held lock, whatever the state of
the transaction that holds the lock
(
<code class="literal">
INNODB_TRX.TRX_STATE
</code>
is
<code class="literal">
RUNNING
</code>
,
<code class="literal">
LOCK WAIT
</code>
,
<code class="literal">
ROLLING BACK
</code>
or
<code class="literal">
COMMITTING
</code>
).
</p>
</li>
<li class="listitem">
<p>
Each transaction in InnoDB that is waiting for another
transaction to release a lock
(
<code class="literal">
INNODB_TRX.TRX_STATE
</code>
is
<code class="literal">
LOCK
WAIT
</code>
) is blocked by exactly one blocking lock
request. That blocking lock request is for a row or table
lock held by another transaction in an incompatible mode.
A lock request always has a mode that is incompatible with
the mode of the held lock that blocks the request (read
vs. write, shared vs. exclusive).
</p>
<p>
The blocked transaction cannot proceed until the other
transaction commits or rolls back, thereby releasing the
requested lock. For every blocked transaction,
<a class="link" href="performance-schema-data-locks-table.html" title="29.12.13.1 The data_locks Table">
<code class="literal">
data_locks
</code>
</a>
contains one row
that describes each lock the transaction has requested,
and for which it is waiting.
</p>
</li>
</ul>
</div>
<a class="indexterm" name="idm46045151222528">
</a>
</li>
<li class="listitem">
<p>
<a class="link" href="performance-schema-data-lock-waits-table.html" title="29.12.13.2 The data_lock_waits Table">
<code class="literal">
data_lock_waits
</code>
</a>
: This Performance
Schema table indicates which transactions are waiting for a
given lock, or for which lock a given transaction is waiting.
This table contains one or more rows for each blocked
transaction, indicating the lock it has requested and any
locks that are blocking that request. The
<code class="literal">
REQUESTING_ENGINE_LOCK_ID
</code>
value refers to
the lock requested by a transaction, and the
<code class="literal">
BLOCKING_ENGINE_LOCK_ID
</code>
value refers to the
lock (held by another transaction) that prevents the first
transaction from proceeding. For any given blocked
transaction, all rows in
<a class="link" href="performance-schema-data-lock-waits-table.html" title="29.12.13.2 The data_lock_waits Table">
<code class="literal">
data_lock_waits
</code>
</a>
have the same
value for
<code class="literal">
REQUESTING_ENGINE_LOCK_ID
</code>
and
different values for
<code class="literal">
BLOCKING_ENGINE_LOCK_ID
</code>
.
</p>
<a class="indexterm" name="idm46045151214192">
</a>
</li>
</ul>
</div>
<p>
For more information about the preceding tables, see
<a class="xref" href="information-schema-innodb-trx-table.html" title="28.4.28 The INFORMATION_SCHEMA INNODB_TRX Table">
Section 28.4.28, “The INFORMATION_SCHEMA INNODB_TRX Table”
</a>
,
<a class="xref" href="performance-schema-data-locks-table.html" title="29.12.13.1 The data_locks Table">
Section 29.12.13.1, “The data_locks Table”
</a>
, and
<a class="xref" href="performance-schema-data-lock-waits-table.html" title="29.12.13.2 The data_lock_waits Table">
Section 29.12.13.2, “The data_lock_waits Table”
</a>
.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/information-schema-user-privileges-table.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="information-schema-user-privileges-table">
</a>
28.3.46 The INFORMATION_SCHEMA USER_PRIVILEGES Table
</h3>
</div>
</div>
</div>
<a class="indexterm" name="idm46045078052832">
</a>
<p>
The
<a class="link" href="information-schema-user-privileges-table.html" title="28.3.46 The INFORMATION_SCHEMA USER_PRIVILEGES Table">
<code class="literal">
USER_PRIVILEGES
</code>
</a>
table provides
information about global privileges. It takes its values from the
<code class="literal">
mysql.user
</code>
system table.
</p>
<p>
The
<a class="link" href="information-schema-user-privileges-table.html" title="28.3.46 The INFORMATION_SCHEMA USER_PRIVILEGES Table">
<code class="literal">
USER_PRIVILEGES
</code>
</a>
table has these
columns:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<code class="literal">
GRANTEE
</code>
</p>
<p>
The name of the account to which the privilege is granted, in
<code class="literal">
'
<em class="replaceable">
<code>
user_name
</code>
</em>
'@'
<em class="replaceable">
<code>
host_name
</code>
</em>
'
</code>
format.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
TABLE_CATALOG
</code>
</p>
<p>
The name of the catalog. This value is always
<code class="literal">
def
</code>
.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
PRIVILEGE_TYPE
</code>
</p>
<p>
The privilege granted. The value can be any privilege that can
be granted at the global level; see
<a class="xref" href="grant.html" title="15.7.1.6 GRANT Statement">
Section 15.7.1.6, “GRANT Statement”
</a>
.
Each row lists a single privilege, so there is one row per
global privilege held by the grantee.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
IS_GRANTABLE
</code>
</p>
<p>
<code class="literal">
YES
</code>
if the user has the
<a class="link" href="privileges-provided.html#priv_grant-option">
<code class="literal">
GRANT OPTION
</code>
</a>
privilege,
<code class="literal">
NO
</code>
otherwise. The output does not list
<a class="link" href="privileges-provided.html#priv_grant-option">
<code class="literal">
GRANT OPTION
</code>
</a>
as a separate row
with
<code class="literal">
PRIVILEGE_TYPE='GRANT OPTION'
</code>
.
</p>
</li>
</ul>
</div>
<h4>
<a name="idm46045078031376">
</a>
Notes
</h4>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<a class="link" href="information-schema-user-privileges-table.html" title="28.3.46 The INFORMATION_SCHEMA USER_PRIVILEGES Table">
<code class="literal">
USER_PRIVILEGES
</code>
</a>
is a nonstandard
<code class="literal">
INFORMATION_SCHEMA
</code>
table.
</p>
</li>
</ul>
</div>
<p>
The following statements are
<span class="emphasis">
<em>
not
</em>
</span>
equivalent:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa64046256"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">SELECT</span> <span class="token punctuation">.</span><span class="token punctuation">.</span><span class="token punctuation">.</span> <span class="token keyword">FROM</span> INFORMATION_SCHEMA<span class="token punctuation">.</span>USER_PRIVILEGES
<span class="token keyword">SHOW</span> <span class="token keyword">GRANTS</span> <span class="token punctuation">.</span><span class="token punctuation">.</span><span class="token punctuation">.</span></code></pre>
</div>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/replication-snapshot-method.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="replication-snapshot-method">
</a>
19.1.2.5 Choosing a Method for Data Snapshots
</h4>
</div>
</div>
</div>
<p>
If the source database contains existing data it is necessary to
copy this data to each replica. There are different ways to dump
the data from the source database. The following sections
describe possible options.
</p>
<p>
To select the appropriate method of dumping the database, choose
between these options:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
Use the
<a class="link" href="mysqldump.html" title="6.5.4 mysqldump — A Database Backup Program">
<span class="command">
<strong>
mysqldump
</strong>
</span>
</a>
tool to create a dump
of all the databases you want to replicate. This is the
recommended method, especially when using
<a class="link" href="innodb-storage-engine.html" title="Chapter 17 The InnoDB Storage Engine">
<code class="literal">
InnoDB
</code>
</a>
.
</p>
</li>
<li class="listitem">
<p>
If your database is stored in binary portable files, you can
copy the raw data files to a replica. This can be more
efficient than using
<a class="link" href="mysqldump.html" title="6.5.4 mysqldump — A Database Backup Program">
<span class="command">
<strong>
mysqldump
</strong>
</span>
</a>
and
importing the file on each replica, because it skips the
overhead of updating indexes as the
<code class="literal">
INSERT
</code>
statements are replayed. With
storage engines such as
<a class="link" href="innodb-storage-engine.html" title="Chapter 17 The InnoDB Storage Engine">
<code class="literal">
InnoDB
</code>
</a>
this is not recommended.
</p>
</li>
<li class="listitem">
<p>
Use MySQL Server's clone plugin to transfer all the data
from an existing replica to a clone. For instructions to use
this method, see
<a class="xref" href="clone-plugin-replication.html" title="7.6.7.7 Cloning for Replication">
Section 7.6.7.7, “Cloning for Replication”
</a>
.
</p>
</li>
</ul>
</div>
<div class="tip" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Tip
</div>
<p>
To deploy multiple instances of MySQL, you can use
<a class="ulink" href="/doc/mysql-shell/8.4/en/mysql-innodb-cluster.html" target="_top">
InnoDB Cluster
</a>
which enables you to easily administer a group of MySQL server instances in
<a class="ulink" href="/doc/mysql-shell/8.4/en/" target="_top">
MySQL Shell
</a>
. InnoDB Cluster wraps MySQL Group Replication in a programmatic environment that enables you easily deploy a cluster of MySQL instances to achieve high availability. In addition, InnoDB Cluster interfaces seamlessly with
<a class="ulink" href="/doc/mysql-router/8.4/en/" target="_top">
MySQL Router
</a>
, which enables your applications to connect to the cluster without writing your own failover process. For similar use cases that do not require high availability, however, you can use
<a class="ulink" href="/doc/mysql-shell/8.4/en/mysql-innodb-replicaset.html" target="_top">
InnoDB ReplicaSet
</a>
. Installation instructions for MySQL Shell can be found
<a class="ulink" href="/doc/mysql-shell/8.4/en/mysql-shell-install.html" target="_top">
here
</a>
.
</p>
</div>
<div class="section">
<div class="titlepage">
<div>
<div>
<h5 class="title">
<a name="replication-howto-mysqldump">
</a>
19.1.2.5.1 Creating a Data Snapshot Using mysqldump
</h5>
</div>
</div>
</div>
<p>
To create a snapshot of the data in an existing source
database, use the
<a class="link" href="mysqldump.html" title="6.5.4 mysqldump — A Database Backup Program">
<span class="command">
<strong>
mysqldump
</strong>
</span>
</a>
tool. Once the
data dump has been completed, import this data into the
replica before starting the replication process.
</p>
<p>
The following example dumps all databases to a file named
<code class="filename">
dbdump.db
</code>
, and includes the
<a class="link" href="mysqldump.html#option_mysqldump_source-data">
<code class="option">
--source-data
</code>
</a>
option which
automatically appends the
<a class="link" href="change-replication-source-to.html" title="15.4.2.2 CHANGE REPLICATION SOURCE TO Statement">
<code class="literal">
CHANGE
REPLICATION SOURCE TO
</code>
</a>
statement required on the
replica to start the replication process:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-terminal"><div class="docs-select-all right" id="sa62492222"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal"><span class="token prompt">$> </span><span class="token command">mysqldump</span> <span class="token property">--all-databases</span> <span class="token property">--source-data</span> > dbdump<span class="token punctuation">.</span>db</code></pre>
</div>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Note
</div>
<p>
If you do not use
<a class="link" href="mysqldump.html#option_mysqldump_source-data">
<code class="option">
--source-data
</code>
</a>
, then it is
necessary to lock all tables in a separate session manually.
See
<a class="xref" href="replication-howto-masterstatus.html" title="19.1.2.4 Obtaining the Replication Source Binary Log Coordinates">
Section 19.1.2.4, “Obtaining the Replication Source Binary Log Coordinates”
</a>
.
</p>
</div>
<p>
It is possible to exclude certain databases from the dump
using the
<a class="link" href="mysqldump.html" title="6.5.4 mysqldump — A Database Backup Program">
<span class="command">
<strong>
mysqldump
</strong>
</span>
</a>
tool. If you want to
choose which databases to include in the dump, do not use
<a class="link" href="mysqldump.html#option_mysqldump_all-databases">
<code class="option">
--all-databases
</code>
</a>
. Choose one
of these options:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
Exclude all the tables in the database using
<a class="link" href="mysqldump.html#option_mysqldump_ignore-table">
<code class="option">
--ignore-table
</code>
</a>
option.
</p>
</li>
<li class="listitem">
<p>
Name only those databases which you want dumped using the
<a class="link" href="mysqldump.html#option_mysqldump_databases">
<code class="option">
--databases
</code>
</a>
option.
</p>
</li>
</ul>
</div>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Note
</div>
<p>
By default, if GTIDs are in use on the source
(
<a class="link" href="replication-options-gtids.html#sysvar_gtid_mode">
<code class="literal">
gtid_mode=ON
</code>
</a>
),
<a class="link" href="mysqldump.html" title="6.5.4 mysqldump — A Database Backup Program">
<span class="command">
<strong>
mysqldump
</strong>
</span>
</a>
includes the GTIDs from the
<a class="link" href="replication-options-gtids.html#sysvar_gtid_executed">
<code class="literal">
gtid_executed
</code>
</a>
set on the
source in the dump output to add them to the
<a class="link" href="replication-options-gtids.html#sysvar_gtid_purged">
<code class="literal">
gtid_purged
</code>
</a>
set on the
replica. If you are dumping only specific databases or
tables, it is important to note that the value that is
included by
<a class="link" href="mysqldump.html" title="6.5.4 mysqldump — A Database Backup Program">
<span class="command">
<strong>
mysqldump
</strong>
</span>
</a>
includes the GTIDs
of all transactions in the
<a class="link" href="replication-options-gtids.html#sysvar_gtid_executed">
<code class="literal">
gtid_executed
</code>
</a>
set on the
source, even those that changed suppressed parts of the
database, or other databases on the server that were not
included in the partial dump. Check the description for
mysqldump's
<code class="option">
--set-gtid-purged
</code>
option to
find the outcome of the default behavior for the MySQL
Server versions you are using, and how to change the
behavior if this outcome is not suitable for your situation.
</p>
</div>
<p>
For more information, see
<a class="xref" href="mysqldump.html" title="6.5.4 mysqldump — A Database Backup Program">
Section 6.5.4, “mysqldump — A Database Backup Program”
</a>
.
</p>
<p>
To import the data, either copy the dump file to the replica,
or access the file from the source when connecting remotely to
the replica.
</p>
</div>
<div class="section">
<div class="titlepage">
<div>
<div>
<h5 class="title">
<a name="replication-howto-rawdata">
</a>
19.1.2.5.2 Creating a Data Snapshot Using Raw Data Files
</h5>
</div>
</div>
</div>
<p>
This section describes how to create a data snapshot using the
raw files which make up the database.
Employing this method with a table using a storage engine that
has complex caching or logging algorithms requires extra steps
to produce a perfect
<span class="quote">
“
<span class="quote">
point in time
</span>
”
</span>
snapshot:
the initial copy command could leave out cache information and
logging updates, even if you have acquired a global read lock.
How the storage engine responds to this depends on its crash
recovery abilities.
</p>
<p>
If you use
<a class="link" href="innodb-storage-engine.html" title="Chapter 17 The InnoDB Storage Engine">
<code class="literal">
InnoDB
</code>
</a>
tables, you can
use the
<span class="command">
<strong>
mysqlbackup
</strong>
</span>
command from the MySQL Enterprise Backup
component to produce a consistent snapshot. This command
records the log name and offset corresponding to the snapshot
to be used on the replica. MySQL Enterprise Backup is a commercial product that
is included as part of a MySQL Enterprise subscription. See
<a class="xref" href="mysql-enterprise-backup.html" title="32.1 MySQL Enterprise Backup Overview">
Section 32.1, “MySQL Enterprise Backup Overview”
</a>
for detailed
information.
</p>
<p>
This method also does not work reliably if the source and
replica have different values for
<a class="link" href="server-system-variables.html#sysvar_ft_stopword_file">
<code class="literal">
ft_stopword_file
</code>
</a>
,
<a class="link" href="server-system-variables.html#sysvar_ft_min_word_len">
<code class="literal">
ft_min_word_len
</code>
</a>
, or
<a class="link" href="server-system-variables.html#sysvar_ft_max_word_len">
<code class="literal">
ft_max_word_len
</code>
</a>
and you are
copying tables having full-text indexes.
</p>
<p>
Assuming the above exceptions do not apply to your database,
use the
<a class="link" href="glossary.html#glos_cold_backup" title="cold backup">
cold backup
</a>
technique to obtain a reliable binary snapshot of
<code class="literal">
InnoDB
</code>
tables: do a
<a class="link" href="glossary.html#glos_slow_shutdown" title="slow shutdown">
slow shutdown
</a>
of the
MySQL Server, then copy the data files manually.
</p>
<p>
To create a raw data snapshot of
<a class="link" href="myisam-storage-engine.html" title="18.2 The MyISAM Storage Engine">
<code class="literal">
MyISAM
</code>
</a>
tables when your MySQL
data files exist on a single file system, you can use standard
file copy tools such as
<span class="command">
<strong>
cp
</strong>
</span>
or
<span class="command">
<strong>
copy
</strong>
</span>
, a remote copy tool such as
<span class="command">
<strong>
scp
</strong>
</span>
or
<span class="command">
<strong>
rsync
</strong>
</span>
, an
archiving tool such as
<span class="command">
<strong>
zip
</strong>
</span>
or
<span class="command">
<strong>
tar
</strong>
</span>
, or a file system snapshot tool such as
<span class="command">
<strong>
dump
</strong>
</span>
. If you are replicating only certain
databases, copy only those files that relate to those tables.
For
<code class="literal">
InnoDB
</code>
, all tables in all databases are
stored in the
<a class="link" href="glossary.html#glos_system_tablespace" title="system tablespace">
system
tablespace
</a>
files, unless you have the
<a class="link" href="innodb-parameters.html#sysvar_innodb_file_per_table">
<code class="option">
innodb_file_per_table
</code>
</a>
option
enabled.
</p>
<p>
The following files are not required for replication:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
Files relating to the
<code class="literal">
mysql
</code>
database.
</p>
</li>
<li class="listitem">
<p>
The replica's connection metadata repository file
<code class="literal">
master.info
</code>
, if used; the use of this
file is now deprecated (see
<a class="xref" href="replica-logs.html" title="19.2.4 Relay Log and Replication Metadata Repositories">
Section 19.2.4, “Relay Log and Replication Metadata Repositories”
</a>
).
</p>
</li>
<li class="listitem">
<p>
The source's binary log files, with the exception of the
binary log index file if you are going to use this to
locate the source binary log coordinates for the replica.
</p>
</li>
<li class="listitem">
<p>
Any relay log files.
</p>
</li>
</ul>
</div>
<p>
Depending on whether you are using
<code class="literal">
InnoDB
</code>
tables or not, choose one of the following:
</p>
<p>
If you are using
<a class="link" href="innodb-storage-engine.html" title="Chapter 17 The InnoDB Storage Engine">
<code class="literal">
InnoDB
</code>
</a>
tables,
and also to get the most consistent results with a raw data
snapshot, shut down the source server during the process, as
follows:
</p>
<div class="orderedlist">
<ol class="orderedlist" type="1">
<li class="listitem">
<p>
Acquire a read lock and get the source's status. See
<a class="xref" href="replication-howto-masterstatus.html" title="19.1.2.4 Obtaining the Replication Source Binary Log Coordinates">
Section 19.1.2.4, “Obtaining the Replication Source Binary Log Coordinates”
</a>
.
</p>
</li>
<li class="listitem">
<p>
In a separate session, shut down the source server:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-terminal"><div class="docs-select-all right" id="sa63644063"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal"><span class="token prompt">$> </span><span class="token command">mysqladmin</span> shutdown</code></pre>
</div>
</li>
<li class="listitem">
<p>
Make a copy of the MySQL data files. The following
examples show common ways to do this. You need to choose
only one of them:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-terminal"><div class="docs-select-all right" id="sa59437617"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal"><span class="token prompt">$> </span><span class="token command">tar</span> cf <em class="replaceable">/tmp/db<span class="token punctuation">.</span>tar</em> <span class="token punctuation"></span><em class="replaceable"><span class="token punctuation">.</span>/data</em>
<span class="token prompt">$> </span><span class="token command">zip</span> <span class="token property">-r</span> <em class="replaceable">/tmp/db<span class="token punctuation">.</span>zip</em> <span class="token punctuation"></span><em class="replaceable"><span class="token punctuation">.</span>/data</em>
<span class="token prompt">$> </span><span class="token command">rsync</span> <span class="token property">--recursive</span> <span class="token punctuation"></span><em class="replaceable"><span class="token punctuation">.</span>/data</em> <em class="replaceable">/tmp/dbdata</em></code></pre>
</div>
</li>
<li class="listitem">
<p>
Restart the source server.
</p>
</li>
</ol>
</div>
<p>
If you are not using
<a class="link" href="innodb-storage-engine.html" title="Chapter 17 The InnoDB Storage Engine">
<code class="literal">
InnoDB
</code>
</a>
tables, you can get a snapshot of the system from a source
without shutting down the server as described in the following
steps:
</p>
<div class="orderedlist">
<ol class="orderedlist" type="1">
<li class="listitem">
<p>
Acquire a read lock and get the source's status. See
<a class="xref" href="replication-howto-masterstatus.html" title="19.1.2.4 Obtaining the Replication Source Binary Log Coordinates">
Section 19.1.2.4, “Obtaining the Replication Source Binary Log Coordinates”
</a>
.
</p>
</li>
<li class="listitem">
<p>
Make a copy of the MySQL data files. The following
examples show common ways to do this. You need to choose
only one of them:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-terminal"><div class="docs-select-all right" id="sa96749995"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal"><span class="token prompt">$> </span><span class="token command">tar</span> cf <em class="replaceable">/tmp/db<span class="token punctuation">.</span>tar</em> <span class="token punctuation"></span><em class="replaceable"><span class="token punctuation">.</span>/data</em>
<span class="token prompt">$> </span><span class="token command">zip</span> <span class="token property">-r</span> <em class="replaceable">/tmp/db<span class="token punctuation">.</span>zip</em> <span class="token punctuation"></span><em class="replaceable"><span class="token punctuation">.</span>/data</em>
<span class="token prompt">$> </span><span class="token command">rsync</span> <span class="token property">--recursive</span> <span class="token punctuation"></span><em class="replaceable"><span class="token punctuation">.</span>/data</em> <em class="replaceable">/tmp/dbdata</em></code></pre>
</div>
</li>
<li class="listitem">
<p>
In the client where you acquired the read lock, release
the lock:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-sql"><div class="docs-select-all right" id="sa34817234"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">UNLOCK</span> <span class="token keyword">TABLES</span><span class="token punctuation">;</span></code></pre>
</div>
</li>
</ol>
</div>
<p>
Once you have created the archive or copy of the database,
copy the files to each replica before starting the replication
process.
</p>
</div>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/shared-key-cache.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="shared-key-cache">
</a>
10.10.2.1 Shared Key Cache Access
</h4>
</div>
</div>
</div>
<p>
Threads can access key cache buffers simultaneously, subject
to the following conditions:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
A buffer that is not being updated can be accessed by
multiple sessions.
</p>
</li>
<li class="listitem">
<p>
A buffer that is being updated causes sessions that need
to use it to wait until the update is complete.
</p>
</li>
<li class="listitem">
<p>
Multiple sessions can initiate requests that result in
cache block replacements, as long as they do not interfere
with each other (that is, as long as they need different
index blocks, and thus cause different cache blocks to be
replaced).
</p>
</li>
</ul>
</div>
<p>
Shared access to the key cache enables the server to improve
throughput significantly.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/sys-create-synonym-db.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="sys-create-synonym-db">
</a>
30.4.4.1 The create_synonym_db() Procedure
</h4>
</div>
</div>
</div>
<a class="indexterm" name="idm46045061673424">
</a>
<a class="indexterm" name="idm46045061671952">
</a>
<p>
Given a schema name, this procedure creates a synonym schema
containing views that refer to all the tables and views in the
original schema. This can be used, for example, to create a
shorter name by which to refer to a schema with a long name
(such as
<code class="literal">
info
</code>
rather than
<code class="literal">
INFORMATION_SCHEMA
</code>
).
</p>
<div class="simplesect">
<div class="titlepage">
<div>
<div class="simple">
<h5 class="title">
<a name="sys-create-synonym-db-parameters">
</a>
Parameters
</h5>
</div>
</div>
</div>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<code class="literal">
in_db_name VARCHAR(64)
</code>
: The name of
the schema for which to create the synonym.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
in_synonym VARCHAR(64)
</code>
: The name to
use for the synonym schema. This schema must not already
exist.
</p>
</li>
</ul>
</div>
</div>
<div class="simplesect">
<div class="titlepage">
<div>
<div class="simple">
<h5 class="title">
<a name="sys-create-synonym-db-example">
</a>
Example
</h5>
</div>
</div>
</div>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa48571164"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SHOW</span> <span class="token keyword">DATABASES</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> Database <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> information_schema <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> mysql <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> performance_schema <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> sys <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> world <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token prompt">mysql></span> <span class="token keyword">CALL</span> sys<span class="token punctuation">.</span>create_synonym_db<span class="token punctuation">(</span><span class="token string">'INFORMATION_SCHEMA'</span><span class="token punctuation">,</span> <span class="token string">'info'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> summary <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> Created 63 views in the info database <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token prompt">mysql></span> <span class="token keyword">SHOW</span> <span class="token keyword">DATABASES</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> Database <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> information_schema <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> info <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> mysql <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> performance_schema <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> sys <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> world <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token prompt">mysql></span> <span class="token keyword">SHOW</span> <span class="token keyword">FULL</span> <span class="token keyword">TABLES</span> <span class="token keyword">FROM</span> info<span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> Tables_in_info <span class="token punctuation">|</span> Table_type <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> character_sets <span class="token punctuation">|</span> VIEW <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> collation_character_set_applicability <span class="token punctuation">|</span> VIEW <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> collations <span class="token punctuation">|</span> VIEW <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> column_privileges <span class="token punctuation">|</span> VIEW <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> columns <span class="token punctuation">|</span> VIEW <span class="token punctuation">|</span></span>
<span class="token punctuation">.</span><span class="token punctuation">.</span><span class="token punctuation">.</span></code></pre>
</div>
</div>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/problems-with-null.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="problems-with-null">
</a>
B.3.4.3 Problems with NULL Values
</h4>
</div>
</div>
</div>
<a class="indexterm" name="idm46045053605680">
</a>
<a class="indexterm" name="idm46045053604224">
</a>
<p>
The concept of the
<code class="literal">
NULL
</code>
value is a common
source of confusion for newcomers to SQL, who often think that
<code class="literal">
NULL
</code>
is the same thing as an empty string
<code class="literal">
''
</code>
. This is not the case. For example, the
following statements are completely different:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa82091774"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">INSERT</span> <span class="token keyword">INTO</span> my_table <span class="token punctuation">(</span>phone<span class="token punctuation">)</span> <span class="token keyword">VALUES</span> <span class="token punctuation">(</span><span class="token boolean">NULL</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token prompt">mysql></span> <span class="token keyword">INSERT</span> <span class="token keyword">INTO</span> my_table <span class="token punctuation">(</span>phone<span class="token punctuation">)</span> <span class="token keyword">VALUES</span> <span class="token punctuation">(</span><span class="token string">''</span><span class="token punctuation">)</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
Both statements insert a value into the
<code class="literal">
phone
</code>
column, but the first inserts a
<code class="literal">
NULL
</code>
value and the second inserts an empty
string. The meaning of the first can be regarded as
<span class="quote">
“
<span class="quote">
phone number is not known
</span>
”
</span>
and the meaning of
the second can be regarded as
<span class="quote">
“
<span class="quote">
the person is known to
have no phone, and thus no phone number.
</span>
”
</span>
</p>
<p>
To help with
<code class="literal">
NULL
</code>
handling, you can use the
<a class="link" href="comparison-operators.html#operator_is-null">
<code class="literal">
IS NULL
</code>
</a>
and
<a class="link" href="comparison-operators.html#operator_is-not-null">
<code class="literal">
IS
NOT NULL
</code>
</a>
operators and the
<a class="link" href="flow-control-functions.html#function_ifnull">
<code class="literal">
IFNULL()
</code>
</a>
function.
</p>
<p>
In SQL, the
<code class="literal">
NULL
</code>
value is never true in
comparison to any other value, even
<code class="literal">
NULL
</code>
.
An expression that contains
<code class="literal">
NULL
</code>
always
produces a
<code class="literal">
NULL
</code>
value unless otherwise
indicated in the documentation for the operators and functions
involved in the expression. All columns in the following
example return
<code class="literal">
NULL
</code>
:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-sql"><div class="docs-select-all right" id="sa99608300"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token boolean">NULL</span><span class="token punctuation">,</span> <span class="token number">1</span><span class="token operator">+</span><span class="token boolean">NULL</span><span class="token punctuation">,</span> <span class="token function">CONCAT</span><span class="token punctuation">(</span><span class="token string">'Invisible'</span><span class="token punctuation">,</span><span class="token boolean">NULL</span><span class="token punctuation">)</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
To search for column values that are
<code class="literal">
NULL
</code>
,
you cannot use an
<code class="literal">
expr = NULL
</code>
test. The
following statement returns no rows, because
<code class="literal">
expr =
NULL
</code>
is never true for any expression:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-sql"><div class="docs-select-all right" id="sa4286172"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token operator">*</span> <span class="token keyword">FROM</span> my_table <span class="token keyword">WHERE</span> phone <span class="token operator">=</span> <span class="token boolean">NULL</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
To look for
<code class="literal">
NULL
</code>
values, you must use the
<a class="link" href="comparison-operators.html#operator_is-null">
<code class="literal">
IS NULL
</code>
</a>
test. The following
statements show how to find the
<code class="literal">
NULL
</code>
phone
number and the empty phone number:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa50360280"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token operator">*</span> <span class="token keyword">FROM</span> my_table <span class="token keyword">WHERE</span> phone <span class="token operator">IS</span> <span class="token boolean">NULL</span><span class="token punctuation">;</span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token operator">*</span> <span class="token keyword">FROM</span> my_table <span class="token keyword">WHERE</span> phone <span class="token operator">=</span> <span class="token string">''</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
See
<a class="xref" href="working-with-null.html" title="5.3.4.6 Working with NULL Values">
Section 5.3.4.6, “Working with NULL Values”
</a>
, for additional
information and examples.
</p>
<p>
You can add an index on a column that can have
<code class="literal">
NULL
</code>
values if you are using the
<code class="literal">
MyISAM
</code>
,
<code class="literal">
InnoDB
</code>
, or
<code class="literal">
MEMORY
</code>
storage engine. Otherwise, you must
declare an indexed column
<code class="literal">
NOT NULL
</code>
, and you
cannot insert
<code class="literal">
NULL
</code>
into the column.
</p>
<a class="indexterm" name="idm46045053568192">
</a>
<p>
When reading data with
<a class="link" href="load-data.html" title="15.2.9 LOAD DATA Statement">
<code class="literal">
LOAD
DATA
</code>
</a>
, empty or missing columns are updated with
<code class="literal">
''
</code>
. To load a
<code class="literal">
NULL
</code>
value
into a column, use
<code class="literal">
\N
</code>
in the data file. The
literal word
<code class="literal">
NULL
</code>
may also be used under
some circumstances. See
<a class="xref" href="load-data.html" title="15.2.9 LOAD DATA Statement">
Section 15.2.9, “LOAD DATA Statement”
</a>
.
</p>
<p>
When using
<code class="literal">
DISTINCT
</code>
,
<code class="literal">
GROUP
BY
</code>
, or
<code class="literal">
ORDER BY
</code>
, all
<code class="literal">
NULL
</code>
values are regarded as equal.
</p>
<p>
When using
<code class="literal">
ORDER BY
</code>
,
<code class="literal">
NULL
</code>
values are presented first, or last if
you specify
<code class="literal">
DESC
</code>
to sort in descending
order.
</p>
<p>
Aggregate (group) functions such as
<a class="link" href="aggregate-functions.html#function_count">
<code class="literal">
COUNT()
</code>
</a>
,
<a class="link" href="aggregate-functions.html#function_min">
<code class="literal">
MIN()
</code>
</a>
, and
<a class="link" href="aggregate-functions.html#function_sum">
<code class="literal">
SUM()
</code>
</a>
ignore
<code class="literal">
NULL
</code>
values. The exception to this is
<a class="link" href="aggregate-functions.html#function_count">
<code class="literal">
COUNT(*)
</code>
</a>
, which counts rows and
not individual column values. For example, the following
statement produces two counts. The first is a count of the
number of rows in the table, and the second is a count of the
number of non-
<code class="literal">
NULL
</code>
values in the
<code class="literal">
age
</code>
column:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-sql"><div class="docs-select-all right" id="sa20557210"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">COUNT</span><span class="token punctuation">(</span><span class="token operator">*</span><span class="token punctuation">)</span><span class="token punctuation">,</span> <span class="token function">COUNT</span><span class="token punctuation">(</span>age<span class="token punctuation">)</span> <span class="token keyword">FROM</span> person<span class="token punctuation">;</span></code></pre>
</div>
<a class="indexterm" name="idm46045053546448">
</a>
<a class="indexterm" name="idm46045053544960">
</a>
<a class="indexterm" name="idm46045053543472">
</a>
<a class="indexterm" name="idm46045053541984">
</a>
<p>
For some data types, MySQL handles
<code class="literal">
NULL
</code>
values in special ways. For example, if you insert
<code class="literal">
NULL
</code>
into an integer or floating-point
column that has the
<code class="literal">
AUTO_INCREMENT
</code>
attribute, the next number in the sequence is inserted. Under
certain conditions, if you insert
<code class="literal">
NULL
</code>
into
a
<a class="link" href="datetime.html" title="13.2.2 The DATE, DATETIME, and TIMESTAMP Types">
<code class="literal">
TIMESTAMP
</code>
</a>
column, the current
date and time is inserted; this behavior depends in part on
the server SQL mode (see
<a class="xref" href="sql-mode.html" title="7.1.11 Server SQL Modes">
Section 7.1.11, “Server SQL Modes”
</a>
) as well
as the value of the
<a class="link" href="server-system-variables.html#sysvar_explicit_defaults_for_timestamp">
<code class="literal">
explicit_defaults_for_timestamp
</code>
</a>
system variable.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/thread-pool-information-schema-tables.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h2 class="title">
<a name="thread-pool-information-schema-tables">
</a>
28.5 INFORMATION_SCHEMA Thread Pool Tables
</h2>
</div>
</div>
</div>
<div class="toc">
<dl class="toc">
<dt>
<span class="section">
<a href="information-schema-thread-pool-table-reference.html">
28.5.1 INFORMATION_SCHEMA Thread Pool Table Reference
</a>
</span>
</dt>
<dt>
<span class="section">
<a href="information-schema-tp-thread-group-state-table.html">
28.5.2 The INFORMATION_SCHEMA TP_THREAD_GROUP_STATE Table
</a>
</span>
</dt>
<dt>
<span class="section">
<a href="information-schema-tp-thread-group-stats-table.html">
28.5.3 The INFORMATION_SCHEMA TP_THREAD_GROUP_STATS Table
</a>
</span>
</dt>
<dt>
<span class="section">
<a href="information-schema-tp-thread-state-table.html">
28.5.4 The INFORMATION_SCHEMA TP_THREAD_STATE Table
</a>
</span>
</dt>
</dl>
</div>
<a class="indexterm" name="idm46045076102208">
</a>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Note
</div>
<p>
The
<code class="literal">
INFORMATION_SCHEMA
</code>
thread pool tables are
deprecated, and subject to removal in a future version of MySQL.
You should use the versions available as Performance Schema tables
instead. See
<a class="xref" href="performance-schema-thread-pool-tables.html" title="29.12.16 Performance Schema Thread Pool Tables">
Section 29.12.16, “Performance Schema Thread Pool Tables”
</a>
.
Applications should transition away from the old tables to the new
tables. For example, if an application uses this query:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-sql"><div class="docs-select-all right" id="sa87104721"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">SELECT</span> <span class="token operator">*</span> <span class="token keyword">FROM</span> INFORMATION_SCHEMA<span class="token punctuation">.</span>TP_THREAD_STATE<span class="token punctuation">;</span></code></pre>
</div>
<p>
The application should use this query instead:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-sql"><div class="docs-select-all right" id="sa7547241"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">SELECT</span> <span class="token operator">*</span> <span class="token keyword">FROM</span> performance_schema<span class="token punctuation">.</span>tp_thread_state<span class="token punctuation">;</span></code></pre>
</div>
</div>
<p>
The following sections describe the
<code class="literal">
INFORMATION_SCHEMA
</code>
tables associated with the
thread pool plugin (see
<a class="xref" href="thread-pool.html" title="7.6.3 MySQL Enterprise Thread Pool">
Section 7.6.3, “MySQL Enterprise Thread Pool”
</a>
). They provide
information about thread pool operation:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<a class="link" href="information-schema-tp-thread-group-state-table.html" title="28.5.2 The INFORMATION_SCHEMA TP_THREAD_GROUP_STATE Table">
<code class="literal">
TP_THREAD_GROUP_STATE
</code>
</a>
: Information
about thread pool thread group states
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="information-schema-tp-thread-group-stats-table.html" title="28.5.3 The INFORMATION_SCHEMA TP_THREAD_GROUP_STATS Table">
<code class="literal">
TP_THREAD_GROUP_STATS
</code>
</a>
: Thread group
statistics
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="information-schema-tp-thread-state-table.html" title="28.5.4 The INFORMATION_SCHEMA TP_THREAD_STATE Table">
<code class="literal">
TP_THREAD_STATE
</code>
</a>
: Information about
thread pool thread states
</p>
</li>
</ul>
</div>
<p>
Rows in these tables represent snapshots in time. In the case of
<code class="literal">
TP_THREAD_STATE
</code>
, all rows for a thread group
comprise a snapshot in time. Thus, the MySQL server holds the mutex
of the thread group while producing the snapshot. But it does not
hold mutexes on all thread groups at the same time, to prevent a
statement against
<code class="literal">
TP_THREAD_STATE
</code>
from blocking
the entire MySQL server.
</p>
<p>
The
<code class="literal">
INFORMATION_SCHEMA
</code>
thread pool tables are
implemented by individual plugins and the decision whether to load
one can be made independently of the others (see
<a class="xref" href="thread-pool-installation.html" title="7.6.3.2 Thread Pool Installation">
Section 7.6.3.2, “Thread Pool Installation”
</a>
). However, the content of
all the tables depends on the thread pool plugin being enabled. If a
table plugin is enabled but the thread pool plugin is not, the table
becomes visible and can be accessed but is empty.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/key-cache-block-size.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="key-cache-block-size">
</a>
10.10.2.5 Key Cache Block Size
</h4>
</div>
</div>
</div>
<p>
It is possible to specify the size of the block buffers for an
individual key cache using the
<a class="link" href="server-system-variables.html#sysvar_key_cache_block_size">
<code class="literal">
key_cache_block_size
</code>
</a>
variable. This permits tuning of the performance of I/O
operations for index files.
</p>
<p>
The best performance for I/O operations is achieved when the
size of read buffers is equal to the size of the native
operating system I/O buffers. But setting the size of key
nodes equal to the size of the I/O buffer does not always
ensure the best overall performance. When reading the big leaf
nodes, the server pulls in a lot of unnecessary data,
effectively preventing reading other leaf nodes.
</p>
<p>
To control the size of blocks in the
<code class="filename">
.MYI
</code>
index file of
<code class="literal">
MyISAM
</code>
tables, use the
<a class="link" href="server-options.html#option_mysqld_myisam-block-size">
<code class="option">
--myisam-block-size
</code>
</a>
option at
server startup.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-events-waits-history-long-table.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="performance-schema-events-waits-history-long-table">
</a>
29.12.4.3 The events_waits_history_long Table
</h4>
</div>
</div>
</div>
<a class="indexterm" name="idm46045073171376">
</a>
<a class="indexterm" name="idm46045073169872">
</a>
<p>
The
<a class="link" href="performance-schema-events-waits-history-long-table.html" title="29.12.4.3 The events_waits_history_long Table">
<code class="literal">
events_waits_history_long
</code>
</a>
table contains
<em class="replaceable">
<code>
N
</code>
</em>
the most recent
wait events that have ended globally, across all threads. Wait
events are not added to the table until they have ended. When
the table becomes full, the oldest row is discarded when a new
row is added, regardless of which thread generated either row.
</p>
<p>
The Performance Schema autosizes the value of
<em class="replaceable">
<code>
N
</code>
</em>
during server startup. To set the
table size explicitly, set the
<a class="link" href="performance-schema-system-variables.html#sysvar_performance_schema_events_waits_history_long_size">
<code class="literal">
performance_schema_events_waits_history_long_size
</code>
</a>
system variable at server startup.
</p>
<p>
The
<a class="link" href="performance-schema-events-waits-history-long-table.html" title="29.12.4.3 The events_waits_history_long Table">
<code class="literal">
events_waits_history_long
</code>
</a>
table has the same columns as
<a class="link" href="performance-schema-events-waits-current-table.html" title="29.12.4.1 The events_waits_current Table">
<code class="literal">
events_waits_current
</code>
</a>
. See
<a class="xref" href="performance-schema-events-waits-current-table.html" title="29.12.4.1 The events_waits_current Table">
Section 29.12.4.1, “The events_waits_current Table”
</a>
.
Unlike
<a class="link" href="performance-schema-events-waits-current-table.html" title="29.12.4.1 The events_waits_current Table">
<code class="literal">
events_waits_current
</code>
</a>
,
<a class="link" href="performance-schema-events-waits-history-long-table.html" title="29.12.4.3 The events_waits_history_long Table">
<code class="literal">
events_waits_history_long
</code>
</a>
has no
indexing.
</p>
<p>
<a class="link" href="truncate-table.html" title="15.1.37 TRUNCATE TABLE Statement">
<code class="literal">
TRUNCATE TABLE
</code>
</a>
is permitted for
the
<a class="link" href="performance-schema-events-waits-history-long-table.html" title="29.12.4.3 The events_waits_history_long Table">
<code class="literal">
events_waits_history_long
</code>
</a>
table. It removes the rows.
</p>
<p>
For more information about the relationship between the three
wait event tables, see
<a class="xref" href="performance-schema-event-tables.html" title="29.9 Performance Schema Tables for Current and Historical Events">
Section 29.9, “Performance Schema Tables for Current and Historical Events”
</a>
.
</p>
<p>
For information about configuring whether to collect wait
events, see
<a class="xref" href="performance-schema-wait-tables.html" title="29.12.4 Performance Schema Wait Event Tables">
Section 29.12.4, “Performance Schema Wait Event Tables”
</a>
.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-programs-ndb-desc.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="mysql-cluster-programs-ndb-desc">
</a>
25.5.9 ndb_desc — Describe NDB Tables
</h3>
</div>
</div>
</div>
<a class="indexterm" name="idm46045104362160">
</a>
<p>
<a class="link" href="mysql-cluster-programs-ndb-desc.html" title="25.5.9 ndb_desc — Describe NDB Tables">
<span class="command">
<strong>
ndb_desc
</strong>
</span>
</a>
provides a detailed description of
one or more
<a class="link" href="mysql-cluster.html" title="Chapter 25 MySQL NDB Cluster 8.4">
<code class="literal">
NDB
</code>
</a>
tables.
</p>
<h4>
<a name="idm46045104358240">
</a>
Usage
</h4>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-terminal"><div class="docs-select-all right" id="sa65473886"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal">ndb_desc <span class="token property">-c</span> <em class="replaceable">connection_string</em> <em class="replaceable">tbl_name</em> <span class="token property">-d</span> <em class="replaceable">db_name</em> <span class="token punctuation">[</span><em class="replaceable">options</em><span class="token punctuation">]</span>
ndb_desc <span class="token property">-c</span> <em class="replaceable">connection_string</em> <em class="replaceable">index_name</em> <span class="token property">-d</span> <em class="replaceable">db_name</em> <span class="token property">-t</span> <em class="replaceable">tbl_name</em></code></pre>
</div>
<p>
Additional options that can be used with
<a class="link" href="mysql-cluster-programs-ndb-desc.html" title="25.5.9 ndb_desc — Describe NDB Tables">
<span class="command">
<strong>
ndb_desc
</strong>
</span>
</a>
are listed later in this section.
</p>
<h4>
<a name="idm46045104351328">
</a>
Sample Output
</h4>
<p>
MySQL table creation and population statements:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa45158647"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">USE</span> test<span class="token punctuation">;</span>
<span class="token keyword">CREATE</span> <span class="token keyword">TABLE</span> fish <span class="token punctuation">(</span>
id <span class="token datatype">INT</span> <span class="token operator">NOT</span> <span class="token boolean">NULL</span> <span class="token keyword">AUTO_INCREMENT</span><span class="token punctuation">,</span>
<span class="token keyword">name</span> <span class="token datatype">VARCHAR</span><span class="token punctuation">(</span><span class="token number">20</span><span class="token punctuation">)</span> <span class="token operator">NOT</span> <span class="token boolean">NULL</span><span class="token punctuation">,</span>
length_mm <span class="token datatype">INT</span> <span class="token operator">NOT</span> <span class="token boolean">NULL</span><span class="token punctuation">,</span>
weight_gm <span class="token datatype">INT</span> <span class="token operator">NOT</span> <span class="token boolean">NULL</span><span class="token punctuation">,</span>
<span class="token keyword">PRIMARY</span> <span class="token keyword">KEY</span> pk <span class="token punctuation">(</span>id<span class="token punctuation">)</span><span class="token punctuation">,</span>
<span class="token keyword">UNIQUE</span> <span class="token keyword">KEY</span> uk <span class="token punctuation">(</span><span class="token keyword">name</span><span class="token punctuation">)</span>
<span class="token punctuation">)</span> <span class="token keyword">ENGINE</span><span class="token operator">=</span><span class="token keyword">NDB</span><span class="token punctuation">;</span>
<span class="token keyword">INSERT</span> <span class="token keyword">INTO</span> fish <span class="token keyword">VALUES</span>
<span class="token punctuation">(</span><span class="token boolean">NULL</span><span class="token punctuation">,</span> <span class="token string">'guppy'</span><span class="token punctuation">,</span> <span class="token number">35</span><span class="token punctuation">,</span> <span class="token number">2</span><span class="token punctuation">)</span><span class="token punctuation">,</span> <span class="token punctuation">(</span><span class="token boolean">NULL</span><span class="token punctuation">,</span> <span class="token string">'tuna'</span><span class="token punctuation">,</span> <span class="token number">2500</span><span class="token punctuation">,</span> <span class="token number">150000</span><span class="token punctuation">)</span><span class="token punctuation">,</span>
<span class="token punctuation">(</span><span class="token boolean">NULL</span><span class="token punctuation">,</span> <span class="token string">'shark'</span><span class="token punctuation">,</span> <span class="token number">3000</span><span class="token punctuation">,</span> <span class="token number">110000</span><span class="token punctuation">)</span><span class="token punctuation">,</span> <span class="token punctuation">(</span><span class="token boolean">NULL</span><span class="token punctuation">,</span> <span class="token string">'manta ray'</span><span class="token punctuation">,</span> <span class="token number">1500</span><span class="token punctuation">,</span> <span class="token number">50000</span><span class="token punctuation">)</span><span class="token punctuation">,</span>
<span class="token punctuation">(</span><span class="token boolean">NULL</span><span class="token punctuation">,</span> <span class="token string">'grouper'</span><span class="token punctuation">,</span> <span class="token number">900</span><span class="token punctuation">,</span> <span class="token number">125000</span><span class="token punctuation">)</span><span class="token punctuation">,</span> <span class="token punctuation">(</span><span class="token boolean">NULL</span> <span class="token punctuation">,</span><span class="token string">'puffer'</span><span class="token punctuation">,</span> <span class="token number">250</span><span class="token punctuation">,</span> <span class="token number">2500</span><span class="token punctuation">)</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
Output from
<a class="link" href="mysql-cluster-programs-ndb-desc.html" title="25.5.9 ndb_desc — Describe NDB Tables">
<span class="command">
<strong>
ndb_desc
</strong>
</span>
</a>
:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-terminal"><div class="docs-select-all right" id="sa50222187"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal"><span class="token prompt">$> </span><span class="token command">./ndb_desc</span> <span class="token property">-c</span> localhost fish <span class="token property">-d</span> test <span class="token property">-p</span>
<span class="token property">--</span> fish <span class="token property">--</span>
Version<span class="token punctuation">:</span> 2
Fragment type<span class="token punctuation">:</span> HashMapPartition
K Value<span class="token punctuation">:</span> 6
Min load factor<span class="token punctuation">:</span> 78
Max load factor<span class="token punctuation">:</span> 80
Temporary table<span class="token punctuation">:</span> no
Number of attributes<span class="token punctuation">:</span> 4
Number of primary keys<span class="token punctuation">:</span> 1
Length of frm data<span class="token punctuation">:</span> 337
Max Rows<span class="token punctuation">:</span> 0
Row Checksum<span class="token punctuation">:</span> 1
Row GCI<span class="token punctuation">:</span> 1
SingleUserMode<span class="token punctuation">:</span> 0
ForceVarPart<span class="token punctuation">:</span> 1
PartitionCount<span class="token punctuation">:</span> 2
FragmentCount<span class="token punctuation">:</span> 2
PartitionBalance<span class="token punctuation">:</span> FOR_RP_BY_LDM
ExtraRowGciBits<span class="token punctuation">:</span> 0
ExtraRowAuthorBits<span class="token punctuation">:</span> 0
TableStatus<span class="token punctuation">:</span> Retrieved
Table options<span class="token punctuation">:</span>
HashMap<span class="token punctuation">:</span> DEFAULT-HASHMAP-3840-2
<span class="token property">--</span> Attributes <span class="token property">--</span>
id Int PRIMARY KEY DISTRIBUTION KEY AT<span class="token attr-value"><span class="token punctuation">=</span>FIXED</span> ST<span class="token attr-value"><span class="token punctuation">=</span>MEMORY</span> AUTO_INCR
name Varchar<span class="token punctuation">(</span>20<span class="token punctuation">;</span>latin1_swedish_ci<span class="token punctuation">)</span> NOT NULL AT<span class="token attr-value"><span class="token punctuation">=</span>SHORT_VAR</span> ST<span class="token attr-value"><span class="token punctuation">=</span>MEMORY</span> DYNAMIC
length_mm Int NOT NULL AT<span class="token attr-value"><span class="token punctuation">=</span>FIXED</span> ST<span class="token attr-value"><span class="token punctuation">=</span>MEMORY</span> DYNAMIC
weight_gm Int NOT NULL AT<span class="token attr-value"><span class="token punctuation">=</span>FIXED</span> ST<span class="token attr-value"><span class="token punctuation">=</span>MEMORY</span> DYNAMIC
<span class="token property">--</span> Indexes <span class="token property">--</span>
PRIMARY KEY<span class="token punctuation">(</span>id<span class="token punctuation">)</span> - UniqueHashIndex
PRIMARY<span class="token punctuation">(</span>id<span class="token punctuation">)</span> - OrderedIndex
uk<span class="token punctuation">(</span>name<span class="token punctuation">)</span> - OrderedIndex
uk$unique<span class="token punctuation">(</span>name<span class="token punctuation">)</span> - UniqueHashIndex
<span class="token property">--</span> Per partition info <span class="token property">--</span>
Partition Row count Commit count Frag fixed memory Frag varsized memory Extent_space Free extent_space
0 2 2 32768 32768 0 0
1 4 4 32768 32768 0 0</code></pre>
</div>
<p>
Information about multiple tables can be obtained in a single
invocation of
<a class="link" href="mysql-cluster-programs-ndb-desc.html" title="25.5.9 ndb_desc — Describe NDB Tables">
<span class="command">
<strong>
ndb_desc
</strong>
</span>
</a>
by using their names,
separated by spaces. All of the tables must be in the same
database.
</p>
<p>
You can obtain additional information about a specific index
using the
<code class="option">
--table
</code>
(short form:
<code class="option">
-t
</code>
) option and supplying the name of the index
as the first argument to
<a class="link" href="mysql-cluster-programs-ndb-desc.html" title="25.5.9 ndb_desc — Describe NDB Tables">
<span class="command">
<strong>
ndb_desc
</strong>
</span>
</a>
, as shown
here:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-terminal"><div class="docs-select-all right" id="sa97885824"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal"><span class="token prompt">$> </span><span class="token command">./ndb_desc</span> uk <span class="token property">-d</span> test <span class="token property">-t</span> fish
<span class="token property">--</span> uk <span class="token property">--</span>
Version<span class="token punctuation">:</span> 2
Base table<span class="token punctuation">:</span> fish
Number of attributes<span class="token punctuation">:</span> 1
Logging<span class="token punctuation">:</span> 0
Index type<span class="token punctuation">:</span> OrderedIndex
Index status<span class="token punctuation">:</span> Retrieved
<span class="token property">--</span> Attributes <span class="token property">--</span>
name Varchar<span class="token punctuation">(</span>20<span class="token punctuation">;</span>latin1_swedish_ci<span class="token punctuation">)</span> NOT NULL AT<span class="token attr-value"><span class="token punctuation">=</span>SHORT_VAR</span> ST<span class="token attr-value"><span class="token punctuation">=</span>MEMORY</span>
<span class="token property">--</span> IndexTable 10/uk <span class="token property">--</span>
Version<span class="token punctuation">:</span> 2
Fragment type<span class="token punctuation">:</span> FragUndefined
K Value<span class="token punctuation">:</span> 6
Min load factor<span class="token punctuation">:</span> 78
Max load factor<span class="token punctuation">:</span> 80
Temporary table<span class="token punctuation">:</span> yes
Number of attributes<span class="token punctuation">:</span> 2
Number of primary keys<span class="token punctuation">:</span> 1
Length of frm data<span class="token punctuation">:</span> 0
Max Rows<span class="token punctuation">:</span> 0
Row Checksum<span class="token punctuation">:</span> 1
Row GCI<span class="token punctuation">:</span> 1
SingleUserMode<span class="token punctuation">:</span> 2
ForceVarPart<span class="token punctuation">:</span> 0
PartitionCount<span class="token punctuation">:</span> 2
FragmentCount<span class="token punctuation">:</span> 2
FragmentCountType<span class="token punctuation">:</span> ONE_PER_LDM_PER_NODE
ExtraRowGciBits<span class="token punctuation">:</span> 0
ExtraRowAuthorBits<span class="token punctuation">:</span> 0
TableStatus<span class="token punctuation">:</span> Retrieved
Table options<span class="token punctuation">:</span>
<span class="token property">--</span> Attributes <span class="token property">--</span>
name Varchar<span class="token punctuation">(</span>20<span class="token punctuation">;</span>latin1_swedish_ci<span class="token punctuation">)</span> NOT NULL AT<span class="token attr-value"><span class="token punctuation">=</span>SHORT_VAR</span> ST<span class="token attr-value"><span class="token punctuation">=</span>MEMORY</span>
NDB$TNODE Unsigned <span class="token punctuation">[</span>64<span class="token punctuation">]</span> PRIMARY KEY DISTRIBUTION KEY AT<span class="token attr-value"><span class="token punctuation">=</span>FIXED</span> ST<span class="token attr-value"><span class="token punctuation">=</span>MEMORY</span>
<span class="token property">--</span> Indexes <span class="token property">--</span>
PRIMARY KEY<span class="token punctuation">(</span>NDB$TNODE<span class="token punctuation">)</span> - UniqueHashIndex</code></pre>
</div>
<p>
When an index is specified in this way, the
<a class="link" href="mysql-cluster-programs-ndb-desc.html#option_ndb_desc_extra-partition-info">
<code class="option">
--extra-partition-info
</code>
</a>
and
<a class="link" href="mysql-cluster-programs-ndb-desc.html#option_ndb_desc_extra-node-info">
<code class="option">
--extra-node-info
</code>
</a>
options have
no effect.
</p>
<p>
The
<code class="literal">
Version
</code>
column in the output contains the
table's schema object version. For information about
interpreting this value, see
<a class="ulink" href="/doc/ndb-internals/en/ndb-internals-schema-object-versions.html" target="_top">
NDB Schema Object Versions
</a>
.
</p>
<p>
Three of the table properties that can be set using
<code class="literal">
NDB_TABLE
</code>
comments embedded in
<a class="link" href="create-table.html" title="15.1.20 CREATE TABLE Statement">
<code class="literal">
CREATE TABLE
</code>
</a>
and
<a class="link" href="alter-table.html" title="15.1.9 ALTER TABLE Statement">
<code class="literal">
ALTER TABLE
</code>
</a>
statements are also
visible in
<a class="link" href="mysql-cluster-programs-ndb-desc.html" title="25.5.9 ndb_desc — Describe NDB Tables">
<span class="command">
<strong>
ndb_desc
</strong>
</span>
</a>
output. The table's
<code class="literal">
FRAGMENT_COUNT_TYPE
</code>
is always shown in the
<code class="literal">
FragmentCountType
</code>
column.
<code class="literal">
READ_ONLY
</code>
and
<code class="literal">
FULLY_REPLICATED
</code>
, if set to 1, are shown in
the
<code class="literal">
Table options
</code>
column. You can see this
after executing the following
<a class="link" href="alter-table.html" title="15.1.9 ALTER TABLE Statement">
<code class="literal">
ALTER
TABLE
</code>
</a>
statement in the
<a class="link" href="mysql.html" title="6.5.1 mysql — The MySQL Command-Line Client">
<span class="command">
<strong>
mysql
</strong>
</span>
</a>
client:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa39763894"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">ALTER</span> <span class="token keyword">TABLE</span> fish <span class="token keyword">COMMENT</span><span class="token operator">=</span><span class="token string">'NDB_TABLE=READ_ONLY=1,FULLY_REPLICATED=1'</span><span class="token punctuation">;</span>
<span class="token output">1 row in set, 1 warning (0.00 sec)</span>
<span class="token prompt">mysql></span> <span class="token keyword">SHOW</span> <span class="token keyword">WARNINGS</span>\G
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> Level <span class="token punctuation">|</span> Code <span class="token punctuation">|</span> Message <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> Warning <span class="token punctuation">|</span> 1296 <span class="token punctuation">|</span> Got error 4503 'Table property is FRAGMENT_COUNT_TYPE=ONE_PER_LDM_PER_NODE but not in comment' from NDB <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output">1 row in set (0.00 sec)</span></code></pre>
</div>
<p>
The warning is issued because
<code class="literal">
READ_ONLY=1
</code>
requires that the table's fragment count type is (or be set
to)
<code class="literal">
ONE_PER_LDM_PER_NODE_GROUP
</code>
;
<code class="literal">
NDB
</code>
sets this automatically in such cases.
You can check that the
<code class="literal">
ALTER TABLE
</code>
statement
has the desired effect using
<a class="link" href="show-create-table.html" title="15.7.7.11 SHOW CREATE TABLE Statement">
<code class="literal">
SHOW CREATE
TABLE
</code>
</a>
:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa7471509"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SHOW</span> <span class="token keyword">CREATE</span> <span class="token keyword">TABLE</span> fish\G
<span class="token output"><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span> 1. row <span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span>
Table<span class="token punctuation">:</span> fish
Create Table<span class="token punctuation">:</span> CREATE TABLE `fish` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`name` varchar(20) NOT NULL,
`length_mm` int(11) NOT NULL,
`weight_gm` int(11) NOT NULL,
PRIMARY KEY (`id`),
UNIQUE KEY `uk` (`name`)
) ENGINE=ndbcluster DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci
COMMENT='NDB_TABLE=READ_BACKUP=1,FULLY_REPLICATED=1'
</span><span class="token output">1 row in set (0.01 sec)</span></code></pre>
</div>
<p>
Because
<code class="literal">
FRAGMENT_COUNT_TYPE
</code>
was not set
explicitly, its value is not shown in the comment text printed
by
<code class="literal">
SHOW CREATE TABLE
</code>
.
<a class="link" href="mysql-cluster-programs-ndb-desc.html" title="25.5.9 ndb_desc — Describe NDB Tables">
<span class="command">
<strong>
ndb_desc
</strong>
</span>
</a>
, however, displays the updated value
for this attribute. The
<code class="literal">
Table options
</code>
column
shows the binary properties just enabled. You can see this in
the output shown here (emphasized text):
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-terminal"><div class="docs-select-all right" id="sa46043361"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal"><span class="token prompt">$> </span><span class="token command">./ndb_desc</span> <span class="token property">-c</span> localhost fish <span class="token property">-d</span> test <span class="token property">-p</span>
<span class="token property">--</span> fish <span class="token property">--</span>
Version<span class="token punctuation">:</span> 4
Fragment type<span class="token punctuation">:</span> HashMapPartition
K Value<span class="token punctuation">:</span> 6
Min load factor<span class="token punctuation">:</span> 78
Max load factor<span class="token punctuation">:</span> 80
Temporary table<span class="token punctuation">:</span> no
Number of attributes<span class="token punctuation">:</span> 4
Number of primary keys<span class="token punctuation">:</span> 1
Length of frm data<span class="token punctuation">:</span> 380
Max Rows<span class="token punctuation">:</span> 0
Row Checksum<span class="token punctuation">:</span> 1
Row GCI<span class="token punctuation">:</span> 1
SingleUserMode<span class="token punctuation">:</span> 0
ForceVarPart<span class="token punctuation">:</span> 1
PartitionCount<span class="token punctuation">:</span> 1
FragmentCount<span class="token punctuation">:</span> 1
<em>FragmentCountType<span class="token punctuation">:</span> ONE_PER_LDM_PER_NODE_GROUP</em>
ExtraRowGciBits<span class="token punctuation">:</span> 0
ExtraRowAuthorBits<span class="token punctuation">:</span> 0
TableStatus<span class="token punctuation">:</span> Retrieved
<em>Table options<span class="token punctuation">:</span> readbackup<span class="token punctuation">,</span> fullyreplicated</em>
HashMap<span class="token punctuation">:</span> DEFAULT-HASHMAP-3840-1
<span class="token property">--</span> Attributes <span class="token property">--</span>
id Int PRIMARY KEY DISTRIBUTION KEY AT<span class="token attr-value"><span class="token punctuation">=</span>FIXED</span> ST<span class="token attr-value"><span class="token punctuation">=</span>MEMORY</span> AUTO_INCR
name Varchar<span class="token punctuation">(</span>20<span class="token punctuation">;</span>latin1_swedish_ci<span class="token punctuation">)</span> NOT NULL AT<span class="token attr-value"><span class="token punctuation">=</span>SHORT_VAR</span> ST<span class="token attr-value"><span class="token punctuation">=</span>MEMORY</span> DYNAMIC
length_mm Int NOT NULL AT<span class="token attr-value"><span class="token punctuation">=</span>FIXED</span> ST<span class="token attr-value"><span class="token punctuation">=</span>MEMORY</span> DYNAMIC
weight_gm Int NOT NULL AT<span class="token attr-value"><span class="token punctuation">=</span>FIXED</span> ST<span class="token attr-value"><span class="token punctuation">=</span>MEMORY</span> DYNAMIC
<span class="token property">--</span> Indexes <span class="token property">--</span>
PRIMARY KEY<span class="token punctuation">(</span>id<span class="token punctuation">)</span> - UniqueHashIndex
PRIMARY<span class="token punctuation">(</span>id<span class="token punctuation">)</span> - OrderedIndex
uk<span class="token punctuation">(</span>name<span class="token punctuation">)</span> - OrderedIndex
uk$unique<span class="token punctuation">(</span>name<span class="token punctuation">)</span> - UniqueHashIndex
<span class="token property">--</span> Per partition info <span class="token property">--</span>
Partition Row count Commit count Frag fixed memory Frag varsized memory Extent_space Free extent_space</code></pre>
</div>
<p>
For more information about these table properties, see
<a class="xref" href="create-table-ndb-comment-options.html" title="15.1.20.12 Setting NDB Comment Options">
Section 15.1.20.12, “Setting NDB Comment Options”
</a>
.
</p>
<p>
The
<code class="literal">
Extent_space
</code>
and
<code class="literal">
Free
extent_space
</code>
columns are applicable only to
<code class="literal">
NDB
</code>
tables having columns on disk; for tables
having only in-memory columns, these columns always contain the
value
<code class="literal">
0
</code>
.
</p>
<p>
To illustrate their use, we modify the previous example. First,
we must create the necessary Disk Data objects, as shown here:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa3520518"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">CREATE</span> <span class="token keyword">LOGFILE</span> <span class="token keyword">GROUP</span> lg_1
<span class="token keyword">ADD</span> <span class="token keyword">UNDOFILE</span> <span class="token string">'undo_1.log'</span>
<span class="token keyword">INITIAL_SIZE</span> 16M
<span class="token keyword">UNDO_BUFFER_SIZE</span> 2M
<span class="token keyword">ENGINE</span> <span class="token keyword">NDB</span><span class="token punctuation">;</span>
<span class="token keyword">ALTER</span> <span class="token keyword">LOGFILE</span> <span class="token keyword">GROUP</span> lg_1
<span class="token keyword">ADD</span> <span class="token keyword">UNDOFILE</span> <span class="token string">'undo_2.log'</span>
<span class="token keyword">INITIAL_SIZE</span> 12M
<span class="token keyword">ENGINE</span> <span class="token keyword">NDB</span><span class="token punctuation">;</span>
<span class="token keyword">CREATE</span> <span class="token keyword">TABLESPACE</span> ts_1
<span class="token keyword">ADD</span> <span class="token keyword">DATAFILE</span> <span class="token string">'data_1.dat'</span>
<span class="token keyword">USE</span> <span class="token keyword">LOGFILE</span> <span class="token keyword">GROUP</span> lg_1
<span class="token keyword">INITIAL_SIZE</span> 32M
<span class="token keyword">ENGINE</span> <span class="token keyword">NDB</span><span class="token punctuation">;</span>
<span class="token keyword">ALTER</span> <span class="token keyword">TABLESPACE</span> ts_1
<span class="token keyword">ADD</span> <span class="token keyword">DATAFILE</span> <span class="token string">'data_2.dat'</span>
<span class="token keyword">INITIAL_SIZE</span> 48M
<span class="token keyword">ENGINE</span> <span class="token keyword">NDB</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
(For more information on the statements just shown and the
objects created by them, see
<a class="xref" href="mysql-cluster-disk-data-objects.html" title="25.6.11.1 NDB Cluster Disk Data Objects">
Section 25.6.11.1, “NDB Cluster Disk Data Objects”
</a>
, as well as
<a class="xref" href="create-logfile-group.html" title="15.1.16 CREATE LOGFILE GROUP Statement">
Section 15.1.16, “CREATE LOGFILE GROUP Statement”
</a>
, and
<a class="xref" href="create-tablespace.html" title="15.1.21 CREATE TABLESPACE Statement">
Section 15.1.21, “CREATE TABLESPACE Statement”
</a>
.)
</p>
<p>
Now we can create and populate a version of the
<code class="literal">
fish
</code>
table that stores 2 of its columns on
disk (deleting the previous version of the table first, if it
already exists):
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa71571622"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">DROP</span> <span class="token keyword">TABLE</span> <span class="token keyword">IF</span> <span class="token keyword">EXISTS</span> fish<span class="token punctuation">;</span>
<span class="token keyword">CREATE</span> <span class="token keyword">TABLE</span> fish <span class="token punctuation">(</span>
id <span class="token datatype">INT</span> <span class="token operator">NOT</span> <span class="token boolean">NULL</span> <span class="token keyword">AUTO_INCREMENT</span><span class="token punctuation">,</span>
<span class="token keyword">name</span> <span class="token datatype">VARCHAR</span><span class="token punctuation">(</span><span class="token number">20</span><span class="token punctuation">)</span> <span class="token operator">NOT</span> <span class="token boolean">NULL</span><span class="token punctuation">,</span>
length_mm <span class="token datatype">INT</span> <span class="token operator">NOT</span> <span class="token boolean">NULL</span><span class="token punctuation">,</span>
weight_gm <span class="token datatype">INT</span> <span class="token operator">NOT</span> <span class="token boolean">NULL</span><span class="token punctuation">,</span>
<span class="token keyword">PRIMARY</span> <span class="token keyword">KEY</span> pk <span class="token punctuation">(</span>id<span class="token punctuation">)</span><span class="token punctuation">,</span>
<span class="token keyword">UNIQUE</span> <span class="token keyword">KEY</span> uk <span class="token punctuation">(</span><span class="token keyword">name</span><span class="token punctuation">)</span>
<span class="token punctuation">)</span> <span class="token keyword">TABLESPACE</span> ts_1 <span class="token keyword">STORAGE</span> <span class="token keyword">DISK</span>
<span class="token keyword">ENGINE</span><span class="token operator">=</span><span class="token keyword">NDB</span><span class="token punctuation">;</span>
<span class="token keyword">INSERT</span> <span class="token keyword">INTO</span> fish <span class="token keyword">VALUES</span>
<span class="token punctuation">(</span><span class="token boolean">NULL</span><span class="token punctuation">,</span> <span class="token string">'guppy'</span><span class="token punctuation">,</span> <span class="token number">35</span><span class="token punctuation">,</span> <span class="token number">2</span><span class="token punctuation">)</span><span class="token punctuation">,</span> <span class="token punctuation">(</span><span class="token boolean">NULL</span><span class="token punctuation">,</span> <span class="token string">'tuna'</span><span class="token punctuation">,</span> <span class="token number">2500</span><span class="token punctuation">,</span> <span class="token number">150000</span><span class="token punctuation">)</span><span class="token punctuation">,</span>
<span class="token punctuation">(</span><span class="token boolean">NULL</span><span class="token punctuation">,</span> <span class="token string">'shark'</span><span class="token punctuation">,</span> <span class="token number">3000</span><span class="token punctuation">,</span> <span class="token number">110000</span><span class="token punctuation">)</span><span class="token punctuation">,</span> <span class="token punctuation">(</span><span class="token boolean">NULL</span><span class="token punctuation">,</span> <span class="token string">'manta ray'</span><span class="token punctuation">,</span> <span class="token number">1500</span><span class="token punctuation">,</span> <span class="token number">50000</span><span class="token punctuation">)</span><span class="token punctuation">,</span>
<span class="token punctuation">(</span><span class="token boolean">NULL</span><span class="token punctuation">,</span> <span class="token string">'grouper'</span><span class="token punctuation">,</span> <span class="token number">900</span><span class="token punctuation">,</span> <span class="token number">125000</span><span class="token punctuation">)</span><span class="token punctuation">,</span> <span class="token punctuation">(</span><span class="token boolean">NULL</span> <span class="token punctuation">,</span><span class="token string">'puffer'</span><span class="token punctuation">,</span> <span class="token number">250</span><span class="token punctuation">,</span> <span class="token number">2500</span><span class="token punctuation">)</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
When run against this version of the table,
<a class="link" href="mysql-cluster-programs-ndb-desc.html" title="25.5.9 ndb_desc — Describe NDB Tables">
<span class="command">
<strong>
ndb_desc
</strong>
</span>
</a>
displays the following output:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-terminal"><div class="docs-select-all right" id="sa50004736"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal"><span class="token prompt">$> </span><span class="token command">./ndb_desc</span> <span class="token property">-c</span> localhost fish <span class="token property">-d</span> test <span class="token property">-p</span>
<span class="token property">--</span> fish <span class="token property">--</span>
Version<span class="token punctuation">:</span> 1
Fragment type<span class="token punctuation">:</span> HashMapPartition
K Value<span class="token punctuation">:</span> 6
Min load factor<span class="token punctuation">:</span> 78
Max load factor<span class="token punctuation">:</span> 80
Temporary table<span class="token punctuation">:</span> no
Number of attributes<span class="token punctuation">:</span> 4
Number of primary keys<span class="token punctuation">:</span> 1
Length of frm data<span class="token punctuation">:</span> 1001
Max Rows<span class="token punctuation">:</span> 0
Row Checksum<span class="token punctuation">:</span> 1
Row GCI<span class="token punctuation">:</span> 1
SingleUserMode<span class="token punctuation">:</span> 0
ForceVarPart<span class="token punctuation">:</span> 1
PartitionCount<span class="token punctuation">:</span> 2
FragmentCount<span class="token punctuation">:</span> 2
PartitionBalance<span class="token punctuation">:</span> FOR_RP_BY_LDM
ExtraRowGciBits<span class="token punctuation">:</span> 0
ExtraRowAuthorBits<span class="token punctuation">:</span> 0
TableStatus<span class="token punctuation">:</span> Retrieved
Table options<span class="token punctuation">:</span> readbackup
HashMap<span class="token punctuation">:</span> DEFAULT-HASHMAP-3840-2
Tablespace id<span class="token punctuation">:</span> 16
Tablespace<span class="token punctuation">:</span> ts_1
<span class="token property">--</span> Attributes <span class="token property">--</span>
id Int PRIMARY KEY DISTRIBUTION KEY AT<span class="token attr-value"><span class="token punctuation">=</span>FIXED</span> ST<span class="token attr-value"><span class="token punctuation">=</span>MEMORY</span> AUTO_INCR
name Varchar<span class="token punctuation">(</span>80<span class="token punctuation">;</span>utf8mb4_0900_ai_ci<span class="token punctuation">)</span> NOT NULL AT<span class="token attr-value"><span class="token punctuation">=</span>SHORT_VAR</span> ST<span class="token attr-value"><span class="token punctuation">=</span>MEMORY</span>
length_mm Int NOT NULL AT<span class="token attr-value"><span class="token punctuation">=</span>FIXED</span> ST<span class="token attr-value"><span class="token punctuation">=</span>DISK</span>
weight_gm Int NOT NULL AT<span class="token attr-value"><span class="token punctuation">=</span>FIXED</span> ST<span class="token attr-value"><span class="token punctuation">=</span>DISK</span>
<span class="token property">--</span> Indexes <span class="token property">--</span>
PRIMARY KEY<span class="token punctuation">(</span>id<span class="token punctuation">)</span> - UniqueHashIndex
PRIMARY<span class="token punctuation">(</span>id<span class="token punctuation">)</span> - OrderedIndex
uk<span class="token punctuation">(</span>name<span class="token punctuation">)</span> - OrderedIndex
uk$unique<span class="token punctuation">(</span>name<span class="token punctuation">)</span> - UniqueHashIndex
<span class="token property">--</span> Per partition info <span class="token property">--</span>
Partition Row count Commit count Frag fixed memory Frag varsized memory Extent_space Free extent_space
0 2 2 32768 32768 1048576 1044440
1 4 4 32768 32768 1048576 1044400</code></pre>
</div>
<p>
This means that 1048576 bytes are allocated from the tablespace
for this table on each partition, of which 1044440 bytes remain
free for additional storage. In other words, 1048576 - 1044440 =
4136 bytes per partition is currently being used to store the
data from this table's disk-based columns. The number of
bytes shown as
<code class="literal">
Free extent_space
</code>
is available
for storing on-disk column data from the
<code class="literal">
fish
</code>
table only; for this reason, it is not visible when selecting
from the Information Schema
<a class="link" href="information-schema-files-table.html" title="28.3.15 The INFORMATION_SCHEMA FILES Table">
<code class="literal">
FILES
</code>
</a>
table.
</p>
<p>
<code class="literal">
Tablespace id
</code>
and
<code class="literal">
Tablespace
</code>
are also displayed for Disk Data
tables.
</p>
<p>
For fully replicated tables,
<a class="link" href="mysql-cluster-programs-ndb-desc.html" title="25.5.9 ndb_desc — Describe NDB Tables">
<span class="command">
<strong>
ndb_desc
</strong>
</span>
</a>
shows
only the nodes holding primary partition fragment replicas;
nodes with copy fragment replicas (only) are ignored. You can
obtain such information, using the
<a class="link" href="mysql.html" title="6.5.1 mysql — The MySQL Command-Line Client">
<span class="command">
<strong>
mysql
</strong>
</span>
</a>
client, from the
<a class="link" href="mysql-cluster-ndbinfo-table-distribution-status.html" title="25.6.17.57 The ndbinfo table_distribution_status Table">
<code class="literal">
table_distribution_status
</code>
</a>
,
<a class="link" href="mysql-cluster-ndbinfo-table-fragments.html" title="25.6.17.58 The ndbinfo table_fragments Table">
<code class="literal">
table_fragments
</code>
</a>
,
<a class="link" href="mysql-cluster-ndbinfo-table-info.html" title="25.6.17.59 The ndbinfo table_info Table">
<code class="literal">
table_info
</code>
</a>
, and
<a class="link" href="mysql-cluster-ndbinfo-table-replicas.html" title="25.6.17.60 The ndbinfo table_replicas Table">
<code class="literal">
table_replicas
</code>
</a>
tables in the
<a class="link" href="mysql-cluster-ndbinfo.html" title="25.6.17 ndbinfo: The NDB Cluster Information Database">
<code class="literal">
ndbinfo
</code>
</a>
database.
</p>
<p>
All options that can be used with
<a class="link" href="mysql-cluster-programs-ndb-desc.html" title="25.5.9 ndb_desc — Describe NDB Tables">
<span class="command">
<strong>
ndb_desc
</strong>
</span>
</a>
are shown in the following table. Additional descriptions follow
the table.
</p>
<p>
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<a name="option_ndb_desc_auto-inc">
</a>
<a class="link" href="mysql-cluster-programs-ndb-desc.html#option_ndb_desc_auto-inc">
<code class="option">
--auto-inc
</code>
</a>
,
<code class="option">
-a
</code>
</p>
<a class="indexterm" name="idm46045104263744">
</a>
<a class="indexterm" name="idm46045104262256">
</a>
<p>
Show the next value for a table's
<code class="literal">
AUTO_INCREMENT
</code>
column, if it has one.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_desc_blob-info">
</a>
<a class="link" href="mysql-cluster-programs-ndb-desc.html#option_ndb_desc_blob-info">
<code class="option">
--blob-info
</code>
</a>
,
<code class="option">
-b
</code>
</p>
<a class="indexterm" name="idm46045104256912">
</a>
<a class="indexterm" name="idm46045104255424">
</a>
<p>
Include information about subordinate
<a class="link" href="blob.html" title="13.3.4 The BLOB and TEXT Types">
<code class="literal">
BLOB
</code>
</a>
and
<a class="link" href="blob.html" title="13.3.4 The BLOB and TEXT Types">
<code class="literal">
TEXT
</code>
</a>
columns.
</p>
<p>
Use of this option also requires the use of the
<a class="link" href="mysql-cluster-programs-ndb-desc.html#option_ndb_desc_extra-partition-info">
<code class="option">
--extra-partition-info
</code>
</a>
(
<code class="option">
-p
</code>
) option.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_desc_character-sets-dir">
</a>
<a class="link" href="mysql-cluster-programs-ndb-desc.html#option_ndb_desc_character-sets-dir">
<code class="option">
--character-sets-dir
</code>
</a>
</p>
<a class="indexterm" name="idm46045104246816">
</a>
<a class="indexterm" name="idm46045104245360">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for character-sets-dir">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--character-sets-dir=path
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Directory containing character sets.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_desc_connect-retries">
</a>
<a class="link" href="mysql-cluster-programs-ndb-desc.html#option_ndb_desc_connect-retries">
<code class="option">
--connect-retries
</code>
</a>
</p>
<a class="indexterm" name="idm46045104235504">
</a>
<a class="indexterm" name="idm46045104234016">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for connect-retries">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--connect-retries=#
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Integer
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
12
</code>
</td>
</tr>
<tr>
<th>
Minimum Value
</th>
<td>
<code class="literal">
0
</code>
</td>
</tr>
<tr>
<th>
Maximum Value
</th>
<td>
<code class="literal">
12
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Number of times to retry connection before giving up.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_desc_connect-retry-delay">
</a>
<a class="link" href="mysql-cluster-programs-ndb-desc.html#option_ndb_desc_connect-retry-delay">
<code class="option">
--connect-retry-delay
</code>
</a>
</p>
<a class="indexterm" name="idm46045104214928">
</a>
<a class="indexterm" name="idm46045104213472">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for connect-retry-delay">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--connect-retry-delay=#
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Integer
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
5
</code>
</td>
</tr>
<tr>
<th>
Minimum Value
</th>
<td>
<code class="literal">
0
</code>
</td>
</tr>
<tr>
<th>
Maximum Value
</th>
<td>
<code class="literal">
5
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Number of seconds to wait between attempts to contact
management server.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_desc_connect-string">
</a>
<a class="link" href="mysql-cluster-programs-ndb-desc.html#option_ndb_desc_connect-string">
<code class="option">
--connect-string
</code>
</a>
</p>
<a class="indexterm" name="idm46045104194288">
</a>
<a class="indexterm" name="idm46045104192800">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for connect-string">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--connect-string=connection_string
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
String
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
[none]
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Same as
<a class="link" href="mysql-cluster-programs-ndb-desc.html#option_ndb_desc_ndb-connectstring">
<code class="option">
--ndb-connectstring
</code>
</a>
.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_desc_context">
</a>
<a class="link" href="mysql-cluster-programs-ndb-desc.html#option_ndb_desc_context">
<code class="option">
--context
</code>
</a>
,
<code class="option">
-x
</code>
</p>
<a class="indexterm" name="idm46045104177072">
</a>
<a class="indexterm" name="idm46045104175584">
</a>
<p>
Show additional contextual information for the table such as
schema, database name, table name, and the table's
internal ID.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_desc_core-file">
</a>
<a class="link" href="mysql-cluster-programs-ndb-desc.html#option_ndb_desc_core-file">
<code class="option">
--core-file
</code>
</a>
</p>
<a class="indexterm" name="idm46045104171232">
</a>
<a class="indexterm" name="idm46045104169744">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for core-file">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--core-file
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Write core file on error; used in debugging.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_desc_database">
</a>
<a class="link" href="mysql-cluster-programs-ndb-desc.html#option_ndb_desc_database">
<code class="option">
--database=
<em class="replaceable">
<code>
db_name
</code>
</em>
</code>
</a>
,
<code class="option">
-d
</code>
</p>
<a class="indexterm" name="idm46045104159328">
</a>
<a class="indexterm" name="idm46045104157840">
</a>
<p>
Specify the database in which the table should be found.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_desc_defaults-extra-file">
</a>
<a class="link" href="mysql-cluster-programs-ndb-desc.html#option_ndb_desc_defaults-extra-file">
<code class="option">
--defaults-extra-file
</code>
</a>
</p>
<a class="indexterm" name="idm46045104153680">
</a>
<a class="indexterm" name="idm46045104152224">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for defaults-extra-file">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--defaults-extra-file=path
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
String
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
[none]
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Read given file after global files are read.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_desc_defaults-file">
</a>
<a class="link" href="mysql-cluster-programs-ndb-desc.html#option_ndb_desc_defaults-file">
<code class="option">
--defaults-file
</code>
</a>
</p>
<a class="indexterm" name="idm46045104137984">
</a>
<a class="indexterm" name="idm46045104136496">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for defaults-file">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--defaults-file=path
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
String
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
[none]
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Read default options from given file only.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_desc_defaults-group-suffix">
</a>
<a class="link" href="mysql-cluster-programs-ndb-desc.html#option_ndb_desc_defaults-group-suffix">
<code class="option">
--defaults-group-suffix
</code>
</a>
</p>
<a class="indexterm" name="idm46045104122224">
</a>
<a class="indexterm" name="idm46045104120768">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for defaults-group-suffix">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--defaults-group-suffix=string
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
String
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
[none]
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Also read groups with concat(group, suffix).
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_desc_extra-node-info">
</a>
<a class="link" href="mysql-cluster-programs-ndb-desc.html#option_ndb_desc_extra-node-info">
<code class="option">
--extra-node-info
</code>
</a>
,
<code class="option">
-n
</code>
</p>
<a class="indexterm" name="idm46045104106176">
</a>
<a class="indexterm" name="idm46045104104688">
</a>
<p>
Include information about the mappings between table
partitions and the data nodes upon which they reside. This
information can be useful for verifying distribution
awareness mechanisms and supporting more efficient
application access to the data stored in NDB Cluster.
</p>
<p>
Use of this option also requires the use of the
<a class="link" href="mysql-cluster-programs-ndb-desc.html#option_ndb_desc_extra-partition-info">
<code class="option">
--extra-partition-info
</code>
</a>
(
<code class="option">
-p
</code>
) option.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_desc_extra-partition-info">
</a>
<a class="link" href="mysql-cluster-programs-ndb-desc.html#option_ndb_desc_extra-partition-info">
<code class="option">
--extra-partition-info
</code>
</a>
,
<code class="option">
-p
</code>
</p>
<a class="indexterm" name="idm46045104098032">
</a>
<a class="indexterm" name="idm46045104096576">
</a>
<p>
Print additional information about the table's
partitions.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_desc_help">
</a>
<a class="link" href="mysql-cluster-programs-ndb-desc.html#option_ndb_desc_help">
<code class="option">
--help
</code>
</a>
</p>
<a class="indexterm" name="idm46045104092400">
</a>
<a class="indexterm" name="idm46045104090912">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for help">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--help
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Display help text and exit.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_desc_login-path">
</a>
<a class="link" href="mysql-cluster-programs-ndb-desc.html#option_ndb_desc_login-path">
<code class="option">
--login-path
</code>
</a>
</p>
<a class="indexterm" name="idm46045104081184">
</a>
<a class="indexterm" name="idm46045104079696">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for login-path">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--login-path=path
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
String
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
[none]
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Read given path from login file.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_desc_no-login-paths">
</a>
<a class="link" href="mysql-cluster-programs-ndb-desc.html#option_ndb_desc_no-login-paths">
<code class="option">
--no-login-paths
</code>
</a>
</p>
<a class="indexterm" name="idm46045104065424">
</a>
<a class="indexterm" name="idm46045104063936">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for no-login-paths">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--no-login-paths
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Skips reading options from the login path file.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_desc_ndb-connectstring">
</a>
<a class="link" href="mysql-cluster-programs-ndb-desc.html#option_ndb_desc_ndb-connectstring">
<code class="option">
--ndb-connectstring
</code>
</a>
</p>
<a class="indexterm" name="idm46045104054272">
</a>
<a class="indexterm" name="idm46045104052816">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for ndb-connectstring">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--ndb-connectstring=connection_string
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
String
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
[none]
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Set connect string for connecting to
<a class="link" href="mysql-cluster-programs-ndb-mgmd.html" title="25.5.4 ndb_mgmd — The NDB Cluster Management Server Daemon">
<span class="command">
<strong>
ndb_mgmd
</strong>
</span>
</a>
. Syntax:
<code class="literal">
[nodeid=
<em class="replaceable">
<code>
id
</code>
</em>
;][host=]
<em class="replaceable">
<code>
hostname
</code>
</em>
[:
<em class="replaceable">
<code>
port
</code>
</em>
]
</code>
.
Overrides entries in
<code class="literal">
NDB_CONNECTSTRING
</code>
and
<code class="filename">
my.cnf
</code>
.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_desc_ndb-mgm-tls">
</a>
<a class="link" href="mysql-cluster-programs-ndb-desc.html#option_ndb_desc_ndb-mgm-tls">
<code class="option">
--ndb-mgm-tls
</code>
</a>
</p>
<a class="indexterm" name="idm46045104033840">
</a>
<a class="indexterm" name="idm46045104032352">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for ndb-mgm-tls">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--ndb-mgm-tls=level
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Enumeration
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
relaxed
</code>
</td>
</tr>
<tr>
<th>
Valid Values
</th>
<td>
<p class="valid-value">
<code class="literal">
relaxed
</code>
</p>
<p class="valid-value">
<code class="literal">
strict
</code>
</p>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Sets the level of TLS support required to connect to the
management server; one of
<code class="literal">
relaxed
</code>
or
<code class="literal">
strict
</code>
.
<code class="literal">
relaxed
</code>
(the
default) means that a TLS connection is attempted, but
success is not required;
<code class="literal">
strict
</code>
means
that TLS is required to connect.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_desc_ndb-mgmd-host">
</a>
<a class="link" href="mysql-cluster-programs-ndb-desc.html#option_ndb_desc_ndb-mgmd-host">
<code class="option">
--ndb-mgmd-host
</code>
</a>
</p>
<a class="indexterm" name="idm46045104011280">
</a>
<a class="indexterm" name="idm46045104009792">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for ndb-mgmd-host">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--ndb-mgmd-host=connection_string
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
String
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
[none]
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Same as
<a class="link" href="mysql-cluster-programs-ndb-desc.html#option_ndb_desc_ndb-connectstring">
<code class="option">
--ndb-connectstring
</code>
</a>
.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_desc_ndb-nodeid">
</a>
<a class="link" href="mysql-cluster-programs-ndb-desc.html#option_ndb_desc_ndb-nodeid">
<code class="option">
--ndb-nodeid
</code>
</a>
</p>
<a class="indexterm" name="idm46045103994608">
</a>
<a class="indexterm" name="idm46045103993120">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for ndb-nodeid">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--ndb-nodeid=#
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Integer
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
[none]
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Set node ID for this node, overriding any ID set by
<a class="link" href="mysql-cluster-programs-ndb-desc.html#option_ndb_desc_ndb-connectstring">
<code class="option">
--ndb-connectstring
</code>
</a>
.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_desc_ndb-optimized-node-selection">
</a>
<a class="link" href="mysql-cluster-programs-ndb-desc.html#option_ndb_desc_ndb-optimized-node-selection">
<code class="option">
--ndb-optimized-node-selection
</code>
</a>
</p>
<a class="indexterm" name="idm46045103977856">
</a>
<a class="indexterm" name="idm46045103976352">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for ndb-optimized-node-selection">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--ndb-optimized-node-selection
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Enable optimizations for selection of nodes for
transactions. Enabled by default; use
<code class="option">
--skip-ndb-optimized-node-selection
</code>
to
disable.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_desc_ndb-tls-search-path">
</a>
<a class="link" href="mysql-cluster-programs-ndb-desc.html#option_ndb_desc_ndb-tls-search-path">
<code class="option">
--ndb-tls-search-path
</code>
</a>
</p>
<a class="indexterm" name="idm46045103966000">
</a>
<a class="indexterm" name="idm46045103964544">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for ndb-tls-search-path">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--ndb-tls-search-path=list
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Path name
</td>
</tr>
<tr>
<th>
Default Value (Unix)
</th>
<td>
<code class="literal">
$HOME/ndb-tls
</code>
</td>
</tr>
<tr>
<th>
Default Value (Windows)
</th>
<td>
<code class="literal">
$HOMEDIR/ndb-tls
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Specify a list of directories to search for a CA file. On
Unix platforms, the directory names are separated by colons
(
<code class="literal">
:
</code>
); on Windows systems, the semicolon
character (
<code class="literal">
;
</code>
) is used as the separator. A
directory reference may be relative or absolute; it may
contain one or more environment variables, each denoted by a
prefixed dollar sign (
<code class="literal">
$
</code>
), and expanded
prior to use.
</p>
<p>
Searching begins with the leftmost named directory and
proceeds from left to right until a file is found. An empty
string denotes an empty search path, which causes all
searches to fail. A string consisting of a single dot
(
<code class="literal">
.
</code>
) indicates that the search path
limited to the current working directory.
</p>
<p>
If no search path is supplied, the compiled-in default value
is used. This value depends on the platform used: On
Windows, this is
<code class="literal">
\ndb-tls
</code>
; on other
platforms (including Linux), it is
<code class="literal">
$HOME/ndb-tls
</code>
. This can be overridden by
compiling NDB Cluster using
<a class="link" href="source-configuration-options.html#option_cmake_with_ndb_tls_search_path">
<code class="option">
-DWITH_NDB_TLS_SEARCH_PATH
</code>
</a>
.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_desc_no-defaults">
</a>
<a class="link" href="mysql-cluster-programs-ndb-desc.html#option_ndb_desc_no-defaults">
<code class="option">
--no-defaults
</code>
</a>
</p>
<a class="indexterm" name="idm46045103940784">
</a>
<a class="indexterm" name="idm46045103939296">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for no-defaults">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--no-defaults
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Do not read default options from any option file other than
login file.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_desc_print-defaults">
</a>
<a class="link" href="mysql-cluster-programs-ndb-desc.html#option_ndb_desc_print-defaults">
<code class="option">
--print-defaults
</code>
</a>
</p>
<a class="indexterm" name="idm46045103929472">
</a>
<a class="indexterm" name="idm46045103927984">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for print-defaults">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--print-defaults
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Print program argument list and exit.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_desc_retries">
</a>
<a class="link" href="mysql-cluster-programs-ndb-desc.html#option_ndb_desc_retries">
<code class="option">
--retries=
<em class="replaceable">
<code>
#
</code>
</em>
</code>
</a>
,
<code class="option">
-r
</code>
</p>
<a class="indexterm" name="idm46045103917712">
</a>
<a class="indexterm" name="idm46045103916224">
</a>
<p>
Try to connect this many times before giving up. One connect
attempt is made per second.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_desc_table">
</a>
<a class="link" href="mysql-cluster-programs-ndb-desc.html#option_ndb_desc_table">
<code class="option">
--table=
<em class="replaceable">
<code>
tbl_name
</code>
</em>
</code>
</a>
,
<code class="option">
-t
</code>
</p>
<a class="indexterm" name="idm46045103911328">
</a>
<a class="indexterm" name="idm46045103909840">
</a>
<p>
Specify the table in which to look for an index.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_desc_unqualified">
</a>
<a class="link" href="mysql-cluster-programs-ndb-desc.html#option_ndb_desc_unqualified">
<code class="option">
--unqualified
</code>
</a>
,
<code class="option">
-u
</code>
</p>
<a class="indexterm" name="idm46045103905104">
</a>
<a class="indexterm" name="idm46045103903616">
</a>
<p>
Use unqualified table names.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_desc_usage">
</a>
<a class="link" href="mysql-cluster-programs-ndb-desc.html#option_ndb_desc_usage">
<code class="option">
--usage
</code>
</a>
</p>
<a class="indexterm" name="idm46045103899552">
</a>
<a class="indexterm" name="idm46045103898064">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for usage">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--usage
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Display help text and exit; same as
<a class="link" href="mysql-cluster-programs-ndb-desc.html#option_ndb_desc_help">
<code class="option">
--help
</code>
</a>
.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_desc_version">
</a>
<a class="link" href="mysql-cluster-programs-ndb-desc.html#option_ndb_desc_version">
<code class="option">
--version
</code>
</a>
</p>
<a class="indexterm" name="idm46045103887344">
</a>
<a class="indexterm" name="idm46045103885856">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for version">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--version
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Display version information and exit.
</p>
</li>
</ul>
</div>
<p>
Table indexes listed in the output are ordered by ID.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/using-system-variables.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="using-system-variables">
</a>
7.1.9 Using System Variables
</h3>
</div>
</div>
</div>
<div class="toc">
<dl class="toc">
<dt>
<span class="section">
<a href="system-variable-privileges.html">
7.1.9.1 System Variable Privileges
</a>
</span>
</dt>
<dt>
<span class="section">
<a href="dynamic-system-variables.html">
7.1.9.2 Dynamic System Variables
</a>
</span>
</dt>
<dt>
<span class="section">
<a href="persisted-system-variables.html">
7.1.9.3 Persisted System Variables
</a>
</span>
</dt>
<dt>
<span class="section">
<a href="nonpersistible-system-variables.html">
7.1.9.4 Nonpersistible and Persist-Restricted System Variables
</a>
</span>
</dt>
<dt>
<span class="section">
<a href="structured-system-variables.html">
7.1.9.5 Structured System Variables
</a>
</span>
</dt>
</dl>
</div>
<a class="indexterm" name="idm46045266750032">
</a>
<a class="indexterm" name="idm46045266748960">
</a>
<a class="indexterm" name="idm46045266747472">
</a>
<a class="indexterm" name="idm46045266746384">
</a>
<p>
The MySQL server maintains many system variables that configure
its operation.
<a class="xref" href="server-system-variables.html" title="7.1.8 Server System Variables">
Section 7.1.8, “Server System Variables”
</a>
,
describes the meaning of these variables. Each system variable has
a default value. System variables can be set at server startup
using options on the command line or in an option file. Most of
them can be changed dynamically while the server is running by
means of the
<a class="link" href="set-variable.html" title="15.7.6.1 SET Syntax for Variable Assignment">
<code class="literal">
SET
</code>
</a>
statement, which enables you to modify operation of the server
without having to stop and restart it. You can also use system
variable values in expressions.
</p>
<p>
Many system variables are built in. System variables may also be
installed by server plugins or components:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
System variables implemented by a server plugin are exposed
when the plugin is installed and have names that begin with
the plugin name. For example, the
<code class="literal">
audit_log
</code>
plugin implements a system variable named
<a class="link" href="audit-log-reference.html#sysvar_audit_log_policy">
<code class="literal">
audit_log_policy
</code>
</a>
.
</p>
</li>
<li class="listitem">
<p>
System variables implemented by a component are exposed when
the component is installed and have names that begin with a
component-specific prefix. For example, the
<code class="literal">
log_filter_dragnet
</code>
error log filter
component implements a system variable named
<code class="literal">
log_error_filter_rules
</code>
, the full name of
which is
<a class="link" href="server-system-variables.html#sysvar_dragnet.log_error_filter_rules">
<code class="literal">
dragnet.log_error_filter_rules
</code>
</a>
.
To refer to this variable, use the full name.
</p>
</li>
</ul>
</div>
<p>
There are two scopes in which system variables exist. Global
variables affect the overall operation of the server. Session
variables affect its operation for individual client connections.
A given system variable can have both a global and a session
value. Global and session system variables are related as follows:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
When the server starts, it initializes each global variable to
its default value. These defaults can be changed by options
specified on the command line or in an option file. (See
<a class="xref" href="program-options.html" title="6.2.2 Specifying Program Options">
Section 6.2.2, “Specifying Program Options”
</a>
.)
</p>
</li>
<li class="listitem">
<p>
The server also maintains a set of session variables for each
client that connects. The client's session variables are
initialized at connect time using the current values of the
corresponding global variables. For example, a client's SQL
mode is controlled by the session
<a class="link" href="server-system-variables.html#sysvar_sql_mode">
<code class="literal">
sql_mode
</code>
</a>
value, which is
initialized when the client connects to the value of the
global
<a class="link" href="server-system-variables.html#sysvar_sql_mode">
<code class="literal">
sql_mode
</code>
</a>
value.
</p>
<p>
For some system variables, the session value is not
initialized from the corresponding global value; if so, that
is indicated in the variable description.
</p>
</li>
</ul>
</div>
<p>
System variable values can be set globally at server startup by
using options on the command line or in an option file. At
startup, the syntax for system variables is the same as for
command options, so within variable names, dashes and underscores
may be used interchangeably. For example,
<a class="link" href="server-system-variables.html#sysvar_general_log">
<code class="option">
--general_log=ON
</code>
</a>
and
<a class="link" href="server-system-variables.html#sysvar_general_log">
<code class="option">
--general-log=ON
</code>
</a>
are equivalent.
</p>
<p>
When you use a startup option to set a variable that takes a
numeric value, the value can be given with a suffix of
<code class="literal">
K
</code>
,
<code class="literal">
M
</code>
,
<code class="literal">
G
</code>
,
<code class="literal">
T
</code>
,
<code class="literal">
P
</code>
, or
<code class="literal">
E
</code>
(either uppercase or lowercase) to indicate a
multiplier of 1024, 1024
<sup>
2
</sup>
,
1024
<sup>
3
</sup>
,
1024
<sup>
4
</sup>
,
1024
<sup>
5
</sup>
, or
1024
<sup>
6
</sup>
; that is, units of kilobytes,
megabytes, gigabytes, terabytes, petabytes, or ettabytes,
respectively. Thus, the following command starts the server with a
sort buffer size of 256 kilobytes and a maximum packet size of one
gigabyte:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-terminal"><div class="docs-select-all right" id="sa53975136"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal">mysqld <span class="token constant">--sort-buffer-size</span><span class="token attr-value"><span class="token punctuation">=</span>256K</span> <span class="token constant">--max-allowed-packet</span><span class="token attr-value"><span class="token punctuation">=</span>1G</span></code></pre>
</div>
<p>
Within an option file, those variables are set like this:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-ini"><div class="docs-select-all right" id="sa99276664"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-ini"><span class="token selector">[mysqld]</span>
<span class="token constant">sort_buffer_size</span><span class="token attr-value"><span class="token punctuation">=</span>256K</span>
<span class="token constant">max_allowed_packet</span><span class="token attr-value"><span class="token punctuation">=</span>1G</span></code></pre>
</div>
<p>
The lettercase of suffix letters does not matter;
<code class="literal">
256K
</code>
and
<code class="literal">
256k
</code>
are
equivalent, as are
<code class="literal">
1G
</code>
and
<code class="literal">
1g
</code>
.
</p>
<p>
To restrict the maximum value to which a system variable can be
set at runtime with the
<a class="link" href="set-variable.html" title="15.7.6.1 SET Syntax for Variable Assignment">
<code class="literal">
SET
</code>
</a>
statement, specify this maximum by using an option of the form
<code class="option">
--maximum-
<em class="replaceable">
<code>
var_name
</code>
</em>
=
<em class="replaceable">
<code>
value
</code>
</em>
</code>
at server startup. For example, to prevent the value of
<a class="link" href="server-system-variables.html#sysvar_sort_buffer_size">
<code class="literal">
sort_buffer_size
</code>
</a>
from being
increased to more than 32MB at runtime, use the option
<code class="option">
--maximum-sort-buffer-size=32M
</code>
.
</p>
<p>
Many system variables are dynamic and can be changed at runtime by
using the
<a class="link" href="set-variable.html" title="15.7.6.1 SET Syntax for Variable Assignment">
<code class="literal">
SET
</code>
</a>
statement. For a list, see
<a class="xref" href="dynamic-system-variables.html" title="7.1.9.2 Dynamic System Variables">
Section 7.1.9.2, “Dynamic System Variables”
</a>
. To change a system
variable with
<a class="link" href="set-variable.html" title="15.7.6.1 SET Syntax for Variable Assignment">
<code class="literal">
SET
</code>
</a>
, refer
to it by name, optionally preceded by a modifier. At runtime,
system variable names must be written using underscores, not
dashes. The following examples briefly illustrate this syntax:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
Set a global system variable:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa46675623"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">SET</span> <span class="token keyword">GLOBAL</span> max_connections <span class="token operator">=</span> <span class="token number">1000</span><span class="token punctuation">;</span>
<span class="token keyword">SET</span> <span class="token variable">@@GLOBAL.max_connections</span> <span class="token operator">=</span> <span class="token number">1000</span><span class="token punctuation">;</span></code></pre>
</div>
</li>
<li class="listitem">
<p>
Persist a global system variable to the
<code class="filename">
mysqld-auto.cnf
</code>
file (and set the runtime
value):
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa13440677"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">SET</span> <span class="token keyword">PERSIST</span> max_connections <span class="token operator">=</span> <span class="token number">1000</span><span class="token punctuation">;</span>
<span class="token keyword">SET</span> <span class="token variable">@@PERSIST.max_connections</span> <span class="token operator">=</span> <span class="token number">1000</span><span class="token punctuation">;</span></code></pre>
</div>
</li>
<li class="listitem">
<p>
Persist a global system variable to the
<code class="filename">
mysqld-auto.cnf
</code>
file (without setting the
runtime value):
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa78930457"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">SET</span> <span class="token keyword">PERSIST_ONLY</span> back_log <span class="token operator">=</span> <span class="token number">1000</span><span class="token punctuation">;</span>
<span class="token keyword">SET</span> <span class="token variable">@@PERSIST_ONLY.back_log</span> <span class="token operator">=</span> <span class="token number">1000</span><span class="token punctuation">;</span></code></pre>
</div>
</li>
<li class="listitem">
<p>
Set a session system variable:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa52167445"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">SET</span> <span class="token keyword">SESSION</span> sql_mode <span class="token operator">=</span> <span class="token string">'TRADITIONAL'</span><span class="token punctuation">;</span>
<span class="token keyword">SET</span> <span class="token variable">@@SESSION.sql_mode</span> <span class="token operator">=</span> <span class="token string">'TRADITIONAL'</span><span class="token punctuation">;</span>
<span class="token keyword">SET</span> <span class="token variable">@@sql_mode</span> <span class="token operator">=</span> <span class="token string">'TRADITIONAL'</span><span class="token punctuation">;</span></code></pre>
</div>
</li>
</ul>
</div>
<p>
For complete details about
<a class="link" href="set-variable.html" title="15.7.6.1 SET Syntax for Variable Assignment">
<code class="literal">
SET
</code>
</a>
syntax, see
<a class="xref" href="set-variable.html" title="15.7.6.1 SET Syntax for Variable Assignment">
Section 15.7.6.1, “SET Syntax for Variable Assignment”
</a>
. For a description of
the privilege requirements for setting and persisting system
variables, see
<a class="xref" href="system-variable-privileges.html" title="7.1.9.1 System Variable Privileges">
Section 7.1.9.1, “System Variable Privileges”
</a>
</p>
<p>
Suffixes for specifying a value multiplier can be used when
setting a variable at server startup, but not to set the value
with
<a class="link" href="set-variable.html" title="15.7.6.1 SET Syntax for Variable Assignment">
<code class="literal">
SET
</code>
</a>
at runtime. On the other hand, with
<a class="link" href="set-variable.html" title="15.7.6.1 SET Syntax for Variable Assignment">
<code class="literal">
SET
</code>
</a>
you
can assign a variable's value using an expression, which is not
true when you set a variable at server startup. For example, the
first of the following lines is legal at server startup, but the
second is not:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-terminal"><div class="docs-select-all right" id="sa52891527"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal"><span class="token prompt">$> </span><span class="token command">mysql</span> <span class="token constant">--max_allowed_packet</span><span class="token attr-value"><span class="token punctuation">=</span>16M</span>
<span class="token prompt">$> </span><span class="token command">mysql</span> <span class="token constant">--max_allowed_packet</span><span class="token attr-value"><span class="token punctuation">=</span>16*1024*1024</span></code></pre>
</div>
<p>
Conversely, the second of the following lines is legal at runtime,
but the first is not:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-terminal"><div class="docs-select-all right" id="sa59191544"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal"><span class="token prompt">mysql></span><span class="token command"> SET</span> GLOBAL max_allowed_packet<span class="token attr-value"><span class="token punctuation">=</span>16M;</span>
<span class="token prompt">mysql></span><span class="token command"> SET</span> GLOBAL max_allowed_packet<span class="token attr-value"><span class="token punctuation">=</span>16*1024*1024;</span></code></pre>
</div>
<p>
To display system variable names and values, use the
<a class="link" href="show-variables.html" title="15.7.7.41 SHOW VARIABLES Statement">
<code class="literal">
SHOW VARIABLES
</code>
</a>
statement:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa65692601"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SHOW</span> <span class="token keyword">VARIABLES</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> Variable_name <span class="token punctuation">|</span> Value <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> activate_all_roles_on_login <span class="token punctuation">|</span> OFF <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> admin_address <span class="token punctuation">|</span> <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> admin_port <span class="token punctuation">|</span> 33062 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> admin_ssl_ca <span class="token punctuation">|</span> <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> admin_ssl_capath <span class="token punctuation">|</span> <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> admin_ssl_cert <span class="token punctuation">|</span> <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> admin_ssl_cipher <span class="token punctuation">|</span> <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> admin_ssl_crl <span class="token punctuation">|</span> <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> admin_ssl_crlpath <span class="token punctuation">|</span> <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> admin_ssl_key <span class="token punctuation">|</span> <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> admin_tls_ciphersuites <span class="token punctuation">|</span> <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> admin_tls_version <span class="token punctuation">|</span> TLSv1.2,TLSv1.3 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> authentication_policy <span class="token punctuation">|</span> *,, <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> auto_generate_certs <span class="token punctuation">|</span> ON <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> auto_increment_increment <span class="token punctuation">|</span> 1 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> auto_increment_offset <span class="token punctuation">|</span> 1 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> autocommit <span class="token punctuation">|</span> ON <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> automatic_sp_privileges <span class="token punctuation">|</span> ON <span class="token punctuation">|</span></span>
<span class="token punctuation">.</span><span class="token punctuation">.</span><span class="token punctuation">.</span>
<span class="token output"><span class="token punctuation">|</span> version <span class="token punctuation">|</span> 8.4.0 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> version_comment <span class="token punctuation">|</span> Source distribution <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> version_compile_machine <span class="token punctuation">|</span> x86_64 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> version_compile_os <span class="token punctuation">|</span> Linux <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> version_compile_zlib <span class="token punctuation">|</span> 1.2.13 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> wait_timeout <span class="token punctuation">|</span> 28800 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> warning_count <span class="token punctuation">|</span> 0 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> windowing_use_high_precision <span class="token punctuation">|</span> ON <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> xa_detach_on_prepare <span class="token punctuation">|</span> ON <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span></code></pre>
</div>
<p>
With a
<a class="link" href="string-comparison-functions.html#operator_like">
<code class="literal">
LIKE
</code>
</a>
clause, the statement
displays only those variables that match the pattern. To obtain a
specific variable name, use a
<a class="link" href="string-comparison-functions.html#operator_like">
<code class="literal">
LIKE
</code>
</a>
clause as shown:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa99686477"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">SHOW</span> <span class="token keyword">VARIABLES</span> <span class="token operator">LIKE</span> <span class="token string">'max_join_size'</span><span class="token punctuation">;</span>
<span class="token keyword">SHOW</span> <span class="token keyword">SESSION</span> <span class="token keyword">VARIABLES</span> <span class="token operator">LIKE</span> <span class="token string">'max_join_size'</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
To get a list of variables whose name match a pattern, use the
<code class="literal">
%
</code>
wildcard character in a
<a class="link" href="string-comparison-functions.html#operator_like">
<code class="literal">
LIKE
</code>
</a>
clause:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa31536938"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">SHOW</span> <span class="token keyword">VARIABLES</span> <span class="token operator">LIKE</span> <span class="token string">'%size%'</span><span class="token punctuation">;</span>
<span class="token keyword">SHOW</span> <span class="token keyword">GLOBAL</span> <span class="token keyword">VARIABLES</span> <span class="token operator">LIKE</span> <span class="token string">'%size%'</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
Wildcard characters can be used in any position within the pattern
to be matched. Strictly speaking, because
<code class="literal">
_
</code>
is
a wildcard that matches any single character, you should escape it
as
<code class="literal">
\_
</code>
to match it literally. In practice, this
is rarely necessary.
</p>
<p>
For
<a class="link" href="show-variables.html" title="15.7.7.41 SHOW VARIABLES Statement">
<code class="literal">
SHOW VARIABLES
</code>
</a>
, if you specify
neither
<code class="literal">
GLOBAL
</code>
nor
<code class="literal">
SESSION
</code>
,
MySQL returns
<code class="literal">
SESSION
</code>
values.
</p>
<p>
The reason for requiring the
<code class="literal">
GLOBAL
</code>
keyword
when setting
<code class="literal">
GLOBAL
</code>
-only variables but not when
retrieving them is to prevent problems in the future:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
Were a
<code class="literal">
SESSION
</code>
variable to be removed that
has the same name as a
<code class="literal">
GLOBAL
</code>
variable, a
client with privileges sufficient to modify global variables
might accidentally change the
<code class="literal">
GLOBAL
</code>
variable rather than just the
<code class="literal">
SESSION
</code>
variable for its own session.
</p>
</li>
<li class="listitem">
<p>
Were a
<code class="literal">
SESSION
</code>
variable to be added with
the same name as a
<code class="literal">
GLOBAL
</code>
variable, a
client that intends to change the
<code class="literal">
GLOBAL
</code>
variable might find only its own
<code class="literal">
SESSION
</code>
variable changed.
</p>
</li>
</ul>
</div>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-replication-group-member-stats-table.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="performance-schema-replication-group-member-stats-table">
</a>
29.12.11.15 The replication_group_member_stats Table
</h4>
</div>
</div>
</div>
<a class="indexterm" name="idm46045070748880">
</a>
<a class="indexterm" name="idm46045070747376">
</a>
<p>
This table shows statistical information for replication group
members. It is populated only when Group Replication is
running.
</p>
<p>
The
<code class="literal">
replication_group_member_stats
</code>
table
has these columns:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<code class="literal">
CHANNEL_NAME
</code>
</p>
<p>
Name of the Group Replication channel
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
VIEW_ID
</code>
</p>
<p>
Current view identifier for this group.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
MEMBER_ID
</code>
</p>
<p>
The member server UUID. This has a different value for
each member in the group. This also serves as a key
because it is unique to each member.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
COUNT_TRANSACTIONS_IN_QUEUE
</code>
</p>
<p>
The number of transactions in the queue pending conflict
detection checks. Once the transactions have been checked
for conflicts, if they pass the check, they are queued to
be applied as well.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
COUNT_TRANSACTIONS_CHECKED
</code>
</p>
<p>
The number of transactions that have been checked for
conflicts.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
COUNT_CONFLICTS_DETECTED
</code>
</p>
<p>
The number of transactions that have not passed the
conflict detection check.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
COUNT_TRANSACTIONS_ROWS_VALIDATING
</code>
</p>
<p>
Number of transaction rows which can be used for
certification, but have not been garbage collected. Can be
thought of as the current size of the conflict detection
database against which each transaction is certified.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
TRANSACTIONS_COMMITTED_ALL_MEMBERS
</code>
</p>
<p>
The transactions that have been successfully committed on
all members of the replication group, shown as
<a class="xref" href="replication-gtids-concepts.html#replication-gtids-concepts-gtid-sets" title="GTID Sets">
GTID Sets
</a>
.
This is updated at a fixed time interval.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
LAST_CONFLICT_FREE_TRANSACTION
</code>
</p>
<p>
The transaction identifier of the last conflict free
transaction which was checked.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
COUNT_TRANSACTIONS_REMOTE_IN_APPLIER_QUEUE
</code>
</p>
<p>
The number of transactions that this member has received
from the replication group which are waiting to be
applied.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
COUNT_TRANSACTIONS_REMOTE_APPLIED
</code>
</p>
<p>
Number of transactions this member has received from the
group and applied.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
COUNT_TRANSACTIONS_LOCAL_PROPOSED
</code>
</p>
<p>
Number of transactions which originated on this member and
were sent to the group.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
COUNT_TRANSACTIONS_LOCAL_ROLLBACK
</code>
</p>
<p>
Number of transactions which originated on this member and
were rolled back by the group.
</p>
</li>
</ul>
</div>
<p>
The
<a class="link" href="performance-schema-replication-group-member-stats-table.html" title="29.12.11.15 The replication_group_member_stats Table">
<code class="literal">
replication_group_member_stats
</code>
</a>
table has no indexes.
</p>
<p>
<a class="link" href="truncate-table.html" title="15.1.37 TRUNCATE TABLE Statement">
<code class="literal">
TRUNCATE TABLE
</code>
</a>
is not permitted
for the
<a class="link" href="performance-schema-replication-group-member-stats-table.html" title="29.12.11.15 The replication_group_member_stats Table">
<code class="literal">
replication_group_member_stats
</code>
</a>
table.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/windows-start-service.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="windows-start-service">
</a>
2.3.3.8 Starting MySQL as a Windows Service
</h4>
</div>
</div>
</div>
<p>
On Windows, the recommended way to run MySQL is to install it as
a Windows service, so that MySQL starts and stops automatically
when Windows starts and stops. A MySQL server installed as a
service can also be controlled from the command line using
<span class="command">
<strong>
NET
</strong>
</span>
commands, or with the graphical
<span class="command">
<strong>
Services
</strong>
</span>
utility. Generally, to install MySQL
as a Windows service you should be logged in using an account
that has administrator rights.
</p>
<p>
The
<span class="command">
<strong>
Services
</strong>
</span>
utility (the Windows
<span class="command">
<strong>
Service Control Manager
</strong>
</span>
) can be found in the
Windows Control Panel. To avoid conflicts, it is advisable to
close the
<span class="command">
<strong>
Services
</strong>
</span>
utility while performing
server installation or removal operations from the command line.
</p>
<h5>
<a name="idm46045331997104">
</a>
Installing the service
</h5>
<p>
Before installing MySQL as a Windows service, you should first
stop the current server if it is running by using the following
command:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-terminal"><div class="docs-select-all right" id="sa61479605"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal"><span class="token prompt">C:\></span> <span class="token atrule">"C:\Program Files\MySQL\MySQL Server 8.4\bin\mysqladmin"</span>
<span class="token property">-u</span> root shutdown</code></pre>
</div>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Note
</div>
<p>
If the MySQL
<code class="literal">
root
</code>
user account has a
password, you need to invoke
<a class="link" href="mysqladmin.html" title="6.5.2 mysqladmin — A MySQL Server Administration Program">
<span class="command">
<strong>
mysqladmin
</strong>
</span>
</a>
with the
<code class="option">
-p
</code>
option and supply the password
when prompted.
</p>
</div>
<p>
This command invokes the MySQL administrative utility
<a class="link" href="mysqladmin.html" title="6.5.2 mysqladmin — A MySQL Server Administration Program">
<span class="command">
<strong>
mysqladmin
</strong>
</span>
</a>
to connect to the server and tell
it to shut down. The command connects as the MySQL
<code class="literal">
root
</code>
user, which is the default
administrative account in the MySQL grant system.
</p>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Note
</div>
<p>
Users in the MySQL grant system are wholly independent from
any operating system users under Windows.
</p>
</div>
<p>
Install the server as a service using this command:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-terminal"><div class="docs-select-all right" id="sa26248586"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal"><span class="token prompt">C:\></span> <span class="token atrule">"C:\Program Files\MySQL\MySQL Server 8.4\bin\mysqld"</span> <span class="token property">--install</span></code></pre>
</div>
<p>
The service-installation command does not start the server.
Instructions for that are given later in this section.
</p>
<p>
To make it easier to invoke MySQL programs, you can add the path
name of the MySQL
<code class="filename">
bin
</code>
directory to your
Windows system
<code class="literal">
PATH
</code>
environment variable:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
On the Windows desktop, right-click the
<span class="guiicon">
My
Computer
</span>
icon, and select
<span class="guimenuitem">
Properties
</span>
.
</p>
</li>
<li class="listitem">
<p>
Next select the
<span class="guimenuitem">
Advanced
</span>
tab from
the
<span class="guimenu">
System Properties
</span>
menu that appears,
and click the
<span class="guibutton">
Environment Variables
</span>
button.
</p>
</li>
<li class="listitem">
<p>
Under
<span class="guilabel">
System Variables
</span>
, select
<span class="guimenuitem">
Path
</span>
, and then click the
<span class="guibutton">
Edit
</span>
button. The
<span class="guimenu">
Edit System
Variable
</span>
dialogue should appear.
</p>
</li>
<li class="listitem">
<p>
Place your cursor at the end of the text appearing in the
space marked
<span class="guilabel">
Variable Value
</span>
. (Use the
<span class="keycap">
<strong>
End
</strong>
</span>
key to ensure that your cursor is
positioned at the very end of the text in this space.) Then
enter the complete path name of your MySQL
<code class="filename">
bin
</code>
directory (for example,
<code class="literal">
C:\Program Files\MySQL\MySQL Server
8.4\bin
</code>
), and there should be a
semicolon separating this path from any values present in
this field. Dismiss this dialogue, and each dialogue in
turn, by clicking
<span class="guibutton">
OK
</span>
until all of the
dialogues that were opened have been dismissed. You should
now be able to invoke any MySQL executable program by typing
its name at the DOS prompt from any directory on the system,
without having to supply the path. This includes the
servers, the
<a class="link" href="mysql.html" title="6.5.1 mysql — The MySQL Command-Line Client">
<span class="command">
<strong>
mysql
</strong>
</span>
</a>
client, and all MySQL
command-line utilities such as
<a class="link" href="mysqladmin.html" title="6.5.2 mysqladmin — A MySQL Server Administration Program">
<span class="command">
<strong>
mysqladmin
</strong>
</span>
</a>
and
<a class="link" href="mysqldump.html" title="6.5.4 mysqldump — A Database Backup Program">
<span class="command">
<strong>
mysqldump
</strong>
</span>
</a>
.
</p>
<p>
You should not add the MySQL
<code class="filename">
bin
</code>
directory to your Windows
<code class="literal">
PATH
</code>
if you are
running multiple MySQL servers on the same machine.
</p>
</li>
</ul>
</div>
<div class="warning" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Warning
</div>
<p>
You must exercise great care when editing your system
<code class="literal">
PATH
</code>
by hand; accidental deletion or
modification of any portion of the existing
<code class="literal">
PATH
</code>
value can leave you with a
malfunctioning or even unusable system.
</p>
</div>
<p>
The following additional arguments can be used when installing
the service:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
You can specify a service name immediately following the
<code class="option">
--install
</code>
option. The default service name
is
<code class="literal">
MySQL
</code>
.
</p>
</li>
<li class="listitem">
<p>
If a service name is given, it can be followed by a single
option. By convention, this should be
<a class="link" href="option-file-options.html#option_general_defaults-file">
<code class="option">
--defaults-file=
<em class="replaceable">
<code>
file_name
</code>
</em>
</code>
</a>
to specify the name of an option file from which the server
should read options when it starts.
</p>
<p>
The use of a single option other than
<a class="link" href="option-file-options.html#option_general_defaults-file">
<code class="option">
--defaults-file
</code>
</a>
is possible
but discouraged.
<a class="link" href="option-file-options.html#option_general_defaults-file">
<code class="option">
--defaults-file
</code>
</a>
is more
flexible because it enables you to specify multiple startup
options for the server by placing them in the named option
file.
</p>
</li>
<li class="listitem">
<p>
You can also specify a
<code class="option">
--local-service
</code>
option following the service name. This causes the server to
run using the
<code class="literal">
LocalService
</code>
Windows
account that has limited system privileges. If both
<a class="link" href="option-file-options.html#option_general_defaults-file">
<code class="option">
--defaults-file
</code>
</a>
and
<code class="option">
--local-service
</code>
are given following the
service name, they can be in any order.
</p>
</li>
</ul>
</div>
<p>
For a MySQL server that is installed as a Windows service, the
following rules determine the service name and option files that
the server uses:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
If the service-installation command specifies no service
name or the default service name (
<code class="literal">
MySQL
</code>
)
following the
<code class="option">
--install
</code>
option, the server
uses the service name of
<code class="literal">
MySQL
</code>
and reads
options from the
<code class="literal">
[mysqld]
</code>
group in the
standard option files.
</p>
</li>
<li class="listitem">
<p>
If the service-installation command specifies a service name
other than
<code class="literal">
MySQL
</code>
following the
<code class="option">
--install
</code>
option, the server uses that
service name. It reads options from the
<code class="literal">
[mysqld]
</code>
group and the group that has the
same name as the service in the standard option files. This
enables you to use the
<code class="literal">
[mysqld]
</code>
group for
options that should be used by all MySQL services, and an
option group with the service name for use by the server
installed with that service name.
</p>
</li>
<li class="listitem">
<p>
If the service-installation command specifies a
<a class="link" href="option-file-options.html#option_general_defaults-file">
<code class="option">
--defaults-file
</code>
</a>
option after
the service name, the server reads options the same way as
described in the previous item, except that it reads options
only from the named file and ignores the standard option
files.
</p>
</li>
</ul>
</div>
<p>
As a more complex example, consider the following command:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-terminal"><div class="docs-select-all right" id="sa30683358"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal"><span class="token prompt">C:\></span> <span class="token atrule">"C:\Program Files\MySQL\MySQL Server 8.4\bin\mysqld"</span>
<span class="token property">--install</span> MySQL <span class="token constant">--defaults-file</span><span class="token attr-value"><span class="token punctuation">=</span>C:\my-opts.cnf</span></code></pre>
</div>
<p>
Here, the default service name (
<code class="literal">
MySQL
</code>
) is
given after the
<code class="option">
--install
</code>
option. If no
<a class="link" href="option-file-options.html#option_general_defaults-file">
<code class="option">
--defaults-file
</code>
</a>
option had been
given, this command would have the effect of causing the server
to read the
<code class="literal">
[mysqld]
</code>
group from the standard
option files. However, because the
<a class="link" href="option-file-options.html#option_general_defaults-file">
<code class="option">
--defaults-file
</code>
</a>
option is
present, the server reads options from the
<code class="literal">
[mysqld]
</code>
option group, and only from the
named file.
</p>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Note
</div>
<p>
On Windows, if the server is started with the
<a class="link" href="option-file-options.html#option_general_defaults-file">
<code class="option">
--defaults-file
</code>
</a>
and
<a class="link" href="server-options.html#option_mysqld_install">
<code class="option">
--install
</code>
</a>
options,
<a class="link" href="server-options.html#option_mysqld_install">
<code class="option">
--install
</code>
</a>
must be first.
Otherwise,
<code class="literal">
mysqld.exe
</code>
attempts to start the
MySQL server.
</p>
</div>
<p>
You can also specify options as Start parameters in the Windows
<span class="command">
<strong>
Services
</strong>
</span>
utility before you start the MySQL
service.
</p>
<p>
Finally, before trying to start the MySQL service, make sure the
user variables
<code class="literal">
%TEMP%
</code>
and
<code class="literal">
%TMP%
</code>
(and also
<code class="literal">
%TMPDIR%
</code>
,
if it has ever been set) for the operating system user who is to
run the service are pointing to a folder to which the user has
write access. The default user for running the MySQL service is
<code class="literal">
LocalSystem
</code>
, and the default value for its
<code class="literal">
%TEMP%
</code>
and
<code class="literal">
%TMP%
</code>
is
<code class="filename">
C:\Windows\Temp
</code>
, a directory
<code class="literal">
LocalSystem
</code>
has write access to by default.
However, if there are any changes to that default setup (for
example, changes to the user who runs the service or to the
mentioned user variables, or the
<a class="link" href="server-options.html#option_mysqld_tmpdir">
<code class="option">
--tmpdir
</code>
</a>
option has been used to
put the temporary directory somewhere else), the MySQL service
might fail to run because write access to the temporary
directory has not been granted to the proper user.
</p>
<h5>
<a name="idm46045331915136">
</a>
Starting the service
</h5>
<p>
After a MySQL server instance has been installed as a service,
Windows starts the service automatically whenever Windows
starts. The service also can be started immediately from the
<span class="command">
<strong>
Services
</strong>
</span>
utility, or by using an
<span class="command">
<strong>
sc
start
<em class="replaceable">
<code>
mysqld_service_name
</code>
</em>
</strong>
</span>
or
<span class="command">
<strong>
NET START
<em class="replaceable">
<code>
mysqld_service_name
</code>
</em>
</strong>
</span>
command.
<span class="command">
<strong>
SC
</strong>
</span>
and
<span class="command">
<strong>
NET
</strong>
</span>
commands are not case-sensitive.
</p>
<p>
When run as a service,
<a class="link" href="mysqld.html" title="6.3.1 mysqld — The MySQL Server">
<span class="command">
<strong>
mysqld
</strong>
</span>
</a>
has no access
to a console window, so no messages can be seen there. If
<a class="link" href="mysqld.html" title="6.3.1 mysqld — The MySQL Server">
<span class="command">
<strong>
mysqld
</strong>
</span>
</a>
does not start, check the error log to
see whether the server wrote any messages there to indicate the
cause of the problem. The error log is located in the MySQL data
directory (for example,
<code class="filename">
C:\Program Files\MySQL\MySQL
Server 8.4\data
</code>
). It is the file with a
suffix of
<code class="filename">
.err
</code>
.
</p>
<p>
When a MySQL server has been installed as a service, and the
service is running, Windows stops the service automatically when
Windows shuts down. The server also can be stopped manually
using the
<code class="literal">
Services
</code>
utility, the
<span class="command">
<strong>
sc
stop
<em class="replaceable">
<code>
mysqld_service_name
</code>
</em>
</strong>
</span>
command, the
<span class="command">
<strong>
NET STOP
<em class="replaceable">
<code>
mysqld_service_name
</code>
</em>
</strong>
</span>
command, or the
<a class="link" href="mysqladmin.html" title="6.5.2 mysqladmin — A MySQL Server Administration Program">
<span class="command">
<strong>
mysqladmin shutdown
</strong>
</span>
</a>
command.
</p>
<p>
You also have the choice of installing the server as a manual
service if you do not wish for the service to be started
automatically during the boot process. To do this, use the
<code class="option">
--install-manual
</code>
option rather than the
<code class="option">
--install
</code>
option:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-terminal"><div class="docs-select-all right" id="sa87826419"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal"><span class="token prompt">C:\></span> <span class="token atrule">"C:\Program Files\MySQL\MySQL Server 8.4\bin\mysqld"</span> <span class="token property">--install-manual</span></code></pre>
</div>
<h5>
<a name="idm46045331897120">
</a>
Removing the service
</h5>
<p>
To remove a server that is installed as a service, first stop it
if it is running by executing
<span class="command">
<strong>
SC STOP
<em class="replaceable">
<code>
mysqld_service_name
</code>
</em>
</strong>
</span>
or
<span class="command">
<strong>
NET STOP
<em class="replaceable">
<code>
mysqld_service_name
</code>
</em>
</strong>
</span>
. Then
use
<span class="command">
<strong>
SC DELETE
<em class="replaceable">
<code>
mysqld_service_name
</code>
</em>
</strong>
</span>
to
remove it:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-terminal"><div class="docs-select-all right" id="sa923702"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal"><span class="token prompt">C:\></span><span class="token command"> SC</span> DELETE mysql</code></pre>
</div>
<p>
Alternatively, use the
<a class="link" href="mysqld.html" title="6.3.1 mysqld — The MySQL Server">
<span class="command">
<strong>
mysqld
</strong>
</span>
</a>
<a class="link" href="server-options.html#option_mysqld_remove">
<code class="option">
--remove
</code>
</a>
option to remove the
service.
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-terminal"><div class="docs-select-all right" id="sa86230210"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal"><span class="token prompt">C:\></span> <span class="token atrule">"C:\Program Files\MySQL\MySQL Server 8.4\bin\mysqld"</span> <span class="token property">--remove</span></code></pre>
</div>
<p>
If
<a class="link" href="mysqld.html" title="6.3.1 mysqld — The MySQL Server">
<span class="command">
<strong>
mysqld
</strong>
</span>
</a>
is not running as a service, you
can start it from the command line. For instructions, see
<a class="xref" href="windows-start-command-line.html" title="2.3.3.6 Starting MySQL from the Windows Command Line">
Section 2.3.3.6, “Starting MySQL from the Windows Command Line”
</a>
.
</p>
<p>
If you encounter difficulties during installation, see
<a class="xref" href="windows-troubleshooting.html" title="2.3.4 Troubleshooting a Microsoft Windows MySQL Server Installation">
Section 2.3.4, “Troubleshooting a Microsoft Windows MySQL Server Installation”
</a>
.
</p>
<p>
For more information about stopping or removing a Windows
service, see
<a class="xref" href="multiple-windows-services.html" title="7.8.2.2 Starting Multiple MySQL Instances as Windows Services">
Section 7.8.2.2, “Starting Multiple MySQL Instances as Windows Services”
</a>
.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/ldap-pluggable-authentication.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="ldap-pluggable-authentication">
</a>
8.4.1.7 LDAP Pluggable Authentication
</h4>
</div>
</div>
</div>
<a class="indexterm" name="idm46045245399120">
</a>
<a class="indexterm" name="idm46045245397616">
</a>
<a class="indexterm" name="idm46045245396112">
</a>
<a class="indexterm" name="idm46045245394608">
</a>
<a class="indexterm" name="idm46045245393120">
</a>
<a class="indexterm" name="idm46045245392032">
</a>
<a class="indexterm" name="idm46045245390528">
</a>
<a class="indexterm" name="idm46045245389040">
</a>
<a class="indexterm" name="idm46045245387552">
</a>
<a class="indexterm" name="idm46045245386064">
</a>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Note
</div>
<p>
LDAP pluggable authentication is an extension included in
MySQL Enterprise Edition, a commercial product. To learn more about commercial
products, see
<a class="ulink" href="https://www.mysql.com/products/" target="_blank">
https://www.mysql.com/products/
</a>
.
</p>
</div>
<p>
MySQL Enterprise Edition supports an authentication method that enables MySQL
Server to use LDAP (Lightweight Directory Access Protocol) to
authenticate MySQL users by accessing directory services such as
X.500. MySQL uses LDAP to fetch user, credential, and group
information.
</p>
<p>
LDAP pluggable authentication provides these capabilities:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
External authentication: LDAP authentication enables MySQL
Server to accept connections from users defined outside the
MySQL grant tables in LDAP directories.
</p>
</li>
<li class="listitem">
<p>
Proxy user support: LDAP authentication can return to MySQL
a user name different from the external user name passed by
the client program, based on the LDAP groups the external
user is a member of. This means that an LDAP plugin can
return the MySQL user that defines the privileges the
external LDAP-authenticated user should have. For example,
an LDAP user named
<code class="literal">
joe
</code>
can connect and
have the privileges of a MySQL user named
<code class="literal">
developer
</code>
, if the LDAP group for
<code class="literal">
joe
</code>
is
<code class="literal">
developer
</code>
.
</p>
</li>
<li class="listitem">
<p>
Security: Using TLS, connections to the LDAP server can be
secure.
</p>
</li>
</ul>
</div>
<p>
Server and client plugins are available for simple and
SASL-based LDAP authentication. On Microsoft Windows, the server
plugin for SASL-based LDAP authentication is not supported, but
the client plugin is.
</p>
<p>
The following tables show the plugin and library file names for
simple and SASL-based LDAP authentication. The file name suffix
might differ on your system. The files must be located in the
directory named by the
<a class="link" href="server-system-variables.html#sysvar_plugin_dir">
<code class="literal">
plugin_dir
</code>
</a>
system variable.
</p>
<div class="table">
<a name="idm46045245372912">
</a>
<p class="title">
<b>
Table 8.20 Plugin and Library Names for Simple LDAP Authentication
</b>
</p>
<div class="table-contents">
<table summary="Names for the plugins and library file used for simple LDAP password authentication.">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<thead>
<tr>
<th>
Plugin or File
</th>
<th>
Plugin or File Name
</th>
</tr>
</thead>
<tbody>
<tr>
<td>
Server-side plugin name
</td>
<td>
<code class="literal">
authentication_ldap_simple
</code>
</td>
</tr>
<tr>
<td>
Client-side plugin name
</td>
<td>
<code class="literal">
mysql_clear_password
</code>
</td>
</tr>
<tr>
<td>
Library file name
</td>
<td>
<code class="filename">
authentication_ldap_simple.so
</code>
</td>
</tr>
</tbody>
</table>
</div>
</div>
<br class="table-break"/>
<div class="table">
<a name="idm46045245359504">
</a>
<p class="title">
<b>
Table 8.21 Plugin and Library Names for SASL-Based LDAP Authentication
</b>
</p>
<div class="table-contents">
<table summary="Names for the plugins and library file used for SASL-based LDAP password authentication.">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<thead>
<tr>
<th>
Plugin or File
</th>
<th>
Plugin or File Name
</th>
</tr>
</thead>
<tbody>
<tr>
<td>
Server-side plugin name
</td>
<td>
<code class="literal">
authentication_ldap_sasl
</code>
</td>
</tr>
<tr>
<td>
Client-side plugin name
</td>
<td>
<code class="literal">
authentication_ldap_sasl_client
</code>
</td>
</tr>
<tr>
<td>
Library file names
</td>
<td>
<code class="filename">
authentication_ldap_sasl.so
</code>
,
<code class="filename">
authentication_ldap_sasl_client.so
</code>
</td>
</tr>
</tbody>
</table>
</div>
</div>
<br class="table-break"/>
<p>
The library files include only the
<code class="literal">
authentication_ldap_
<em class="replaceable">
<code>
XXX
</code>
</em>
</code>
authentication plugins. The client-side
<code class="literal">
mysql_clear_password
</code>
plugin is built into the
<code class="literal">
libmysqlclient
</code>
client library.
</p>
<p>
Each server-side LDAP plugin works with a specific client-side
plugin:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
The server-side
<code class="literal">
authentication_ldap_simple
</code>
plugin
performs simple LDAP authentication. For connections by
accounts that use this plugin, client programs use the
client-side
<code class="literal">
mysql_clear_password
</code>
plugin,
which sends the password to the server as cleartext. No
password hashing or encryption is used, so a secure
connection between the MySQL client and server is
recommended to prevent password exposure.
</p>
</li>
<li class="listitem">
<p>
The server-side
<code class="literal">
authentication_ldap_sasl
</code>
plugin performs SASL-based LDAP authentication. For
connections by accounts that use this plugin, client
programs use the client-side
<code class="literal">
authentication_ldap_sasl_client
</code>
plugin.
The client-side and server-side SASL LDAP plugins use SASL
messages for secure transmission of credentials within the
LDAP protocol, to avoid sending the cleartext password
between the MySQL client and server.
</p>
<p>
On Microsoft Windows platforms, both the server plugin and
the client plugin are supported for SASL-based LDAP
authentication.
</p>
</li>
</ul>
</div>
<p>
The server-side LDAP authentication plugins are included only in
MySQL Enterprise Edition. They are not included in MySQL community distributions.
The client-side SASL LDAP plugin is included in all
distributions, including community distributions, and, as
mentioned previously, the client-side
<code class="literal">
mysql_clear_password
</code>
plugin is built into the
<code class="literal">
libmysqlclient
</code>
client library, which also is
included in all distributions. This enables clients from any
distribution to connect to a server that has the appropriate
server-side plugin loaded.
</p>
<p>
The following sections provide installation and usage
information specific to LDAP pluggable authentication:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<a class="xref" href="ldap-pluggable-authentication.html#ldap-pluggable-authentication-prerequisites" title="Prerequisites for LDAP Pluggable Authentication">
Prerequisites for LDAP Pluggable Authentication
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="xref" href="ldap-pluggable-authentication.html#ldap-pluggable-authentication-process" title="How LDAP Authentication of MySQL Users Works">
How LDAP Authentication of MySQL Users Works
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="xref" href="ldap-pluggable-authentication.html#ldap-pluggable-authentication-installation" title="Installing LDAP Pluggable Authentication">
Installing LDAP Pluggable Authentication
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="xref" href="ldap-pluggable-authentication.html#ldap-pluggable-authentication-uninstallation" title="Uninstalling LDAP Pluggable Authentication">
Uninstalling LDAP Pluggable Authentication
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="xref" href="ldap-pluggable-authentication.html#ldap-pluggable-authentication-ldap-conf" title="LDAP Pluggable Authentication and ldap.conf">
LDAP Pluggable Authentication and ldap.conf
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="xref" href="ldap-pluggable-authentication.html#ldap-pluggable-authentication-timeouts" title="Setting Timeouts for LDAP Pluggable Authentication">
Setting Timeouts for LDAP Pluggable Authentication
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="xref" href="ldap-pluggable-authentication.html#ldap-pluggable-authentication-usage" title="Using LDAP Pluggable Authentication">
Using LDAP Pluggable Authentication
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="xref" href="ldap-pluggable-authentication.html#ldap-pluggable-authentication-usage-simple" title="Simple LDAP Authentication (Without Proxying)">
Simple LDAP Authentication (Without Proxying)
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="xref" href="ldap-pluggable-authentication.html#ldap-pluggable-authentication-usage-sasl" title="SASL-Based LDAP Authentication (Without Proxying)">
SASL-Based LDAP Authentication (Without Proxying)
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="xref" href="ldap-pluggable-authentication.html#ldap-pluggable-authentication-usage-proxying" title="LDAP Authentication with Proxying">
LDAP Authentication with Proxying
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="xref" href="ldap-pluggable-authentication.html#ldap-pluggable-authentication-usage-group-mapping" title="LDAP Authentication Group Preference and Mapping Specification">
LDAP Authentication Group Preference and Mapping Specification
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="xref" href="ldap-pluggable-authentication.html#ldap-pluggable-authentication-usage-user-dn-suffix" title="LDAP Authentication User DN Suffixes">
LDAP Authentication User DN Suffixes
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="xref" href="ldap-pluggable-authentication.html#ldap-pluggable-authentication-auth-methods" title="LDAP Authentication Methods">
LDAP Authentication Methods
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="xref" href="ldap-pluggable-authentication.html#ldap-pluggable-authentication-gssapi" title="The GSSAPI/Kerberos Authentication Method">
The GSSAPI/Kerberos Authentication Method
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="xref" href="ldap-pluggable-authentication.html#ldap-pluggable-authentication-ldap-referral" title="LDAP Search Referral">
LDAP Search Referral
</a>
</p>
</li>
</ul>
</div>
<p>
For general information about pluggable authentication in MySQL,
see
<a class="xref" href="pluggable-authentication.html" title="8.2.17 Pluggable Authentication">
Section 8.2.17, “Pluggable Authentication”
</a>
. For information
about the
<code class="literal">
mysql_clear_password
</code>
plugin, see
<a class="xref" href="cleartext-pluggable-authentication.html" title="8.4.1.4 Client-Side Cleartext Pluggable Authentication">
Section 8.4.1.4, “Client-Side Cleartext Pluggable Authentication”
</a>
. For proxy
user information, see
<a class="xref" href="proxy-users.html" title="8.2.19 Proxy Users">
Section 8.2.19, “Proxy Users”
</a>
.
</p>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Note
</div>
<p>
If your system supports PAM and permits LDAP as a PAM
authentication method, another way to use LDAP for MySQL user
authentication is to use the server-side
<code class="literal">
authentication_pam
</code>
plugin. See
<a class="xref" href="pam-pluggable-authentication.html" title="8.4.1.5 PAM Pluggable Authentication">
Section 8.4.1.5, “PAM Pluggable Authentication”
</a>
.
</p>
</div>
<div class="simplesect">
<div class="titlepage">
<div>
<div class="simple">
<h5 class="title">
<a name="ldap-pluggable-authentication-prerequisites">
</a>
Prerequisites for LDAP Pluggable Authentication
</h5>
</div>
</div>
</div>
<p>
To use LDAP pluggable authentication for MySQL, these
prerequisites must be satisfied:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
An LDAP server must be available for the LDAP
authentication plugins to communicate with.
</p>
</li>
<li class="listitem">
<p>
LDAP users to be authenticated by MySQL must be present in
the directory managed by the LDAP server.
</p>
</li>
<li class="listitem">
<p>
An LDAP client library must be available on systems where
the server-side
<code class="literal">
authentication_ldap_sasl
</code>
or
<code class="literal">
authentication_ldap_simple
</code>
plugin is
used. Currently, supported libraries are the Windows
native LDAP library, or the OpenLDAP library on
non-Windows systems.
</p>
</li>
<li class="listitem">
<p>
To use SASL-based LDAP authentication:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
The LDAP server must be configured to communicate with
a SASL server.
</p>
</li>
<li class="listitem">
<p>
A SASL client library must be available on systems
where the client-side
<code class="literal">
authentication_ldap_sasl_client
</code>
plugin is used. Currently, the only supported library
is the Cyrus SASL library.
</p>
</li>
<li class="listitem">
<p>
To use a particular SASL authentication method, any
other services required by that method must be
available. For example, to use GSSAPI/Kerberos, a
GSSAPI library and Kerberos services must be
available.
</p>
</li>
</ul>
</div>
</li>
</ul>
</div>
</div>
<div class="simplesect">
<div class="titlepage">
<div>
<div class="simple">
<h5 class="title">
<a name="ldap-pluggable-authentication-process">
</a>
How LDAP Authentication of MySQL Users Works
</h5>
</div>
</div>
</div>
<p>
This section provides an overview of how MySQL and LDAP work
together to authenticate MySQL users. For examples showing how
to set up MySQL accounts to use specific LDAP authentication
plugins, see
<a class="xref" href="ldap-pluggable-authentication.html#ldap-pluggable-authentication-usage" title="Using LDAP Pluggable Authentication">
Using LDAP Pluggable Authentication
</a>
. For
information about authentication methods available to the LDAP
plugins, see
<a class="xref" href="ldap-pluggable-authentication.html#ldap-pluggable-authentication-auth-methods" title="LDAP Authentication Methods">
LDAP Authentication Methods
</a>
.
</p>
<p>
The client connects to the MySQL server, providing the MySQL
client user name and a password:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
For simple LDAP authentication, the client-side and
server-side plugins communicate the password as cleartext.
A secure connection between the MySQL client and server is
recommended to prevent password exposure.
</p>
</li>
<li class="listitem">
<p>
For SASL-based LDAP authentication, the client-side and
server-side plugins avoid sending the cleartext password
between the MySQL client and server. For example, the
plugins might use SASL messages for secure transmission of
credentials within the LDAP protocol. For the GSSAPI
authentication method, the client-side and server-side
plugins communicate securely using Kerberos without using
LDAP messages directly.
</p>
</li>
</ul>
</div>
<p>
If the client user name and host name match no MySQL account,
the connection is rejected.
</p>
<p>
If there is a matching MySQL account, authentication against
LDAP occurs. The LDAP server looks for an entry matching the
user and authenticates the entry against the LDAP password:
</p>
<a class="indexterm" name="idm46045245290928">
</a>
<a class="indexterm" name="idm46045245289440">
</a>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
If the MySQL account names an LDAP user distinguished name
(DN), LDAP authentication uses that value and the LDAP
password provided by the client. (To associate an LDAP
user DN with a MySQL account, include a
<code class="literal">
BY
</code>
clause that specifies an
authentication string in the
<a class="link" href="create-user.html" title="15.7.1.3 CREATE USER Statement">
<code class="literal">
CREATE
USER
</code>
</a>
statement that creates the account.)
</p>
</li>
<li class="listitem">
<p>
If the MySQL account names no LDAP user DN, LDAP
authentication uses the user name and LDAP password
provided by the client. In this case, the authentication
plugin first binds to the LDAP server using the root DN
and password as credentials to find the user DN based on
the client user name, then authenticates that user DN
against the LDAP password. This bind using the root
credentials fails if the root DN and password are set to
incorrect values, or are empty (not set) and the LDAP
server does not permit anonymous connections.
</p>
</li>
</ul>
</div>
<p>
If the LDAP server finds no match or multiple matches,
authentication fails and the client connection is rejected.
</p>
<p>
If the LDAP server finds a single match, LDAP authentication
succeeds (assuming that the password is correct), the LDAP
server returns the LDAP entry, and the authentication plugin
determines the name of the authenticated user based on that
entry:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
If the LDAP entry has a group attribute (by default, the
<code class="literal">
cn
</code>
attribute), the plugin returns its
value as the authenticated user name.
</p>
</li>
<li class="listitem">
<p>
If the LDAP entry has no group attribute, the
authentication plugin returns the client user name as the
authenticated user name.
</p>
</li>
</ul>
</div>
<p>
The MySQL server compares the client user name with the
authenticated user name to determine whether proxying occurs
for the client session:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
If the names are the same, no proxying occurs: The MySQL
account matching the client user name is used for
privilege checking.
</p>
</li>
<li class="listitem">
<p>
If the names differ, proxying occurs: MySQL looks for an
account matching the authenticated user name. That account
becomes the proxied user, which is used for privilege
checking. The MySQL account that matched the client user
name is treated as the external proxy user.
</p>
</li>
</ul>
</div>
</div>
<div class="simplesect">
<div class="titlepage">
<div>
<div class="simple">
<h5 class="title">
<a name="ldap-pluggable-authentication-installation">
</a>
Installing LDAP Pluggable Authentication
</h5>
</div>
</div>
</div>
<p>
This section describes how to install the server-side LDAP
authentication plugins. For general information about
installing plugins, see
<a class="xref" href="plugin-loading.html" title="7.6.1 Installing and Uninstalling Plugins">
Section 7.6.1, “Installing and Uninstalling Plugins”
</a>
.
</p>
<p>
To be usable by the server, the plugin library files must be
located in the MySQL plugin directory (the directory named by
the
<a class="link" href="server-system-variables.html#sysvar_plugin_dir">
<code class="literal">
plugin_dir
</code>
</a>
system
variable). If necessary, configure the plugin directory
location by setting the value of
<a class="link" href="server-system-variables.html#sysvar_plugin_dir">
<code class="literal">
plugin_dir
</code>
</a>
at server startup.
</p>
<p>
The server-side plugin library file base names are
<code class="literal">
authentication_ldap_simple
</code>
and
<code class="literal">
authentication_ldap_sasl
</code>
. The file name
suffix differs per platform (for example,
<code class="filename">
.so
</code>
for Unix and Unix-like systems,
<code class="filename">
.dll
</code>
for Windows).
</p>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Note
</div>
<p>
On Microsoft Windows, the server plugin for SASL-based LDAP
authentication is not supported, but the client plugin is
supported. On other platforms, both the server and client
plugins are supported.
</p>
</div>
<p>
To load the plugins at server startup, use
<a class="link" href="server-options.html#option_mysqld_plugin-load-add">
<code class="option">
--plugin-load-add
</code>
</a>
options to
name the library files that contain them. With this
plugin-loading method, the options must be given each time the
server starts. Also, specify values for any plugin-provided
system variables you wish to configure.
</p>
<p>
Each server-side LDAP plugin exposes a set of system variables
that enable its operation to be configured. Setting most of
these is optional, but you must set the variables that specify
the LDAP server host (so the plugin knows where to connect)
and base distinguished name for LDAP bind operations (to limit
the scope of searches and obtain faster searches). For details
about all LDAP system variables, see
<a class="xref" href="pluggable-authentication-system-variables.html" title="8.4.1.13 Pluggable Authentication System Variables">
Section 8.4.1.13, “Pluggable Authentication System Variables”
</a>
.
</p>
<p>
To load the plugins and set the LDAP server host and base
distinguished name for LDAP bind operations, put lines such as
these in your
<code class="filename">
my.cnf
</code>
file, adjusting the
<code class="filename">
.so
</code>
suffix for your platform as
necessary:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-ini"><div class="docs-select-all right" id="sa12278739"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-ini"><span class="token selector">[mysqld]</span>
<span class="token constant">plugin-load-add</span><span class="token attr-value"><span class="token punctuation">=</span>authentication_ldap_simple.so</span>
<span class="token constant">authentication_ldap_simple_server_host</span><span class="token attr-value"><span class="token punctuation">=</span>127.0.0.1</span>
<span class="token constant">authentication_ldap_simple_bind_base_dn</span><span class="token attr-value"><span class="token punctuation">=</span>"dc=example,dc=com"</span>
<span class="token constant">plugin-load-add</span><span class="token attr-value"><span class="token punctuation">=</span>authentication_ldap_sasl.so</span>
<span class="token constant">authentication_ldap_sasl_server_host</span><span class="token attr-value"><span class="token punctuation">=</span>127.0.0.1</span>
<span class="token constant">authentication_ldap_sasl_bind_base_dn</span><span class="token attr-value"><span class="token punctuation">=</span>"dc=example,dc=com"</span></code></pre>
</div>
<p>
After modifying
<code class="filename">
my.cnf
</code>
, restart the
server to cause the new settings to take effect.
</p>
<p>
Alternatively, to load the plugins at runtime, use these
statements, adjusting the
<code class="filename">
.so
</code>
suffix for
your platform as necessary:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa36975520"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">INSTALL</span> <span class="token keyword">PLUGIN</span> authentication_ldap_simple
<span class="token keyword">SONAME</span> <span class="token string">'authentication_ldap_simple.so'</span><span class="token punctuation">;</span>
<span class="token keyword">INSTALL</span> <span class="token keyword">PLUGIN</span> authentication_ldap_sasl
<span class="token keyword">SONAME</span> <span class="token string">'authentication_ldap_sasl.so'</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
<a class="link" href="install-plugin.html" title="15.7.4.4 INSTALL PLUGIN Statement">
<code class="literal">
INSTALL PLUGIN
</code>
</a>
loads the plugin
immediately, and also registers it in the
<code class="literal">
mysql.plugins
</code>
system table to cause the
server to load it for each subsequent normal startup without
the need for
<a class="link" href="server-options.html#option_mysqld_plugin-load-add">
<code class="option">
--plugin-load-add
</code>
</a>
.
</p>
<p>
After installing the plugins at runtime, the system variables
that they expose become available and you can add settings for
them to your
<code class="filename">
my.cnf
</code>
file to configure the
plugins for subsequent restarts. For example:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-ini"><div class="docs-select-all right" id="sa37153604"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-ini"><span class="token selector">[mysqld]</span>
<span class="token constant">authentication_ldap_simple_server_host</span><span class="token attr-value"><span class="token punctuation">=</span>127.0.0.1</span>
<span class="token constant">authentication_ldap_simple_bind_base_dn</span><span class="token attr-value"><span class="token punctuation">=</span>"dc=example,dc=com"</span>
<span class="token constant">authentication_ldap_sasl_server_host</span><span class="token attr-value"><span class="token punctuation">=</span>127.0.0.1</span>
<span class="token constant">authentication_ldap_sasl_bind_base_dn</span><span class="token attr-value"><span class="token punctuation">=</span>"dc=example,dc=com"</span></code></pre>
</div>
<p>
After modifying
<code class="filename">
my.cnf
</code>
, restart the
server to cause the new settings to take effect.
</p>
<p>
To set and persist each value at runtime rather than at
startup, use these statements:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa96299696"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">SET</span> <span class="token keyword">PERSIST</span> authentication_ldap_simple_server_host<span class="token operator">=</span><span class="token string">'127.0.0.1'</span><span class="token punctuation">;</span>
<span class="token keyword">SET</span> <span class="token keyword">PERSIST</span> authentication_ldap_simple_bind_base_dn<span class="token operator">=</span><span class="token string">'dc=example,dc=com'</span><span class="token punctuation">;</span>
<span class="token keyword">SET</span> <span class="token keyword">PERSIST</span> authentication_ldap_sasl_server_host<span class="token operator">=</span><span class="token string">'127.0.0.1'</span><span class="token punctuation">;</span>
<span class="token keyword">SET</span> <span class="token keyword">PERSIST</span> authentication_ldap_sasl_bind_base_dn<span class="token operator">=</span><span class="token string">'dc=example,dc=com'</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
<a class="link" href="set-variable.html" title="15.7.6.1 SET Syntax for Variable Assignment">
<code class="literal">
SET
PERSIST
</code>
</a>
sets a value for the running MySQL instance.
It also saves the value, causing it to carry over to
subsequent server restarts. To change a value for the running
MySQL instance without having it carry over to subsequent
restarts, use the
<code class="literal">
GLOBAL
</code>
keyword rather
than
<code class="literal">
PERSIST
</code>
. See
<a class="xref" href="set-variable.html" title="15.7.6.1 SET Syntax for Variable Assignment">
Section 15.7.6.1, “SET Syntax for Variable Assignment”
</a>
.
</p>
<p>
To verify plugin installation, examine the Information Schema
<a class="link" href="information-schema-plugins-table.html" title="28.3.22 The INFORMATION_SCHEMA PLUGINS Table">
<code class="literal">
PLUGINS
</code>
</a>
table or use the
<a class="link" href="show-plugins.html" title="15.7.7.27 SHOW PLUGINS Statement">
<code class="literal">
SHOW PLUGINS
</code>
</a>
statement (see
<a class="xref" href="obtaining-plugin-information.html" title="7.6.2 Obtaining Server Plugin Information">
Section 7.6.2, “Obtaining Server Plugin Information”
</a>
). For example:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa52778819"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> PLUGIN_NAME<span class="token punctuation">,</span> PLUGIN_STATUS
<span class="token keyword">FROM</span> INFORMATION_SCHEMA<span class="token punctuation">.</span><span class="token keyword">PLUGINS</span>
<span class="token keyword">WHERE</span> PLUGIN_NAME <span class="token operator">LIKE</span> <span class="token string">'%ldap%'</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> PLUGIN_NAME <span class="token punctuation">|</span> PLUGIN_STATUS <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> authentication_ldap_sasl <span class="token punctuation">|</span> ACTIVE <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> authentication_ldap_simple <span class="token punctuation">|</span> ACTIVE <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span></code></pre>
</div>
<p>
If a plugin fails to initialize, check the server error log
for diagnostic messages.
</p>
<p>
To associate MySQL accounts with an LDAP plugin, see
<a class="xref" href="ldap-pluggable-authentication.html#ldap-pluggable-authentication-usage" title="Using LDAP Pluggable Authentication">
Using LDAP Pluggable Authentication
</a>
.
</p>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Additional Notes for SELinux
</div>
<a class="indexterm" name="idm46045245232496">
</a>
<p>
On systems running EL6 or EL that have SELinux enabled,
changes to the SELinux policy are required to enable the
MySQL LDAP plugins to communicate with the LDAP service:
</p>
<div class="orderedlist">
<ol class="orderedlist" type="1">
<li class="listitem">
<p>
Create a file
<code class="filename">
mysqlldap.te
</code>
with
these contents:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-simple"><div class="docs-select-all right" id="sa41818513"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-simple">module mysqlldap 1<span class="token punctuation">.</span>0<span class="token punctuation">;</span>
require <span class="token punctuation">{</span>
type ldap_port_t<span class="token punctuation">;</span>
type mysqld_t<span class="token punctuation">;</span>
class tcp_socket name_connect<span class="token punctuation">;</span>
<span class="token punctuation">}</span>
<span class="token comment" spellcheck="true">#============= mysqld_t ==============</span>
allow mysqld_t ldap_port_t<span class="token operator">:</span>tcp_socket name_connect<span class="token punctuation">;</span></code></pre>
</div>
</li>
<li class="listitem">
<p>
Compile the security policy module into a binary
representation:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-terminal"><div class="docs-select-all right" id="sa32673821"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal">checkmodule <span class="token property">-M</span> <span class="token property">-m</span> mysqlldap<span class="token punctuation">.</span>te <span class="token property">-o</span> mysqlldap<span class="token punctuation">.</span>mod</code></pre>
</div>
</li>
<li class="listitem">
<p>
Create an SELinux policy module package:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-terminal"><div class="docs-select-all right" id="sa22979606"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal">semodule_package <span class="token property">-m</span> mysqlldap<span class="token punctuation">.</span>mod <span class="token property">-o</span> mysqlldap<span class="token punctuation">.</span>pp</code></pre>
</div>
</li>
<li class="listitem">
<p>
Install the module package:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-terminal"><div class="docs-select-all right" id="sa88637431"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal">semodule <span class="token property">-i</span> mysqlldap<span class="token punctuation">.</span>pp</code></pre>
</div>
</li>
<li class="listitem">
<p>
When the SELinux policy changes have been made, restart
the MySQL server:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-terminal"><div class="docs-select-all right" id="sa72346311"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal">service mysqld restart</code></pre>
</div>
</li>
</ol>
</div>
</div>
</div>
<div class="simplesect">
<div class="titlepage">
<div>
<div class="simple">
<h5 class="title">
<a name="ldap-pluggable-authentication-uninstallation">
</a>
Uninstalling LDAP Pluggable Authentication
</h5>
</div>
</div>
</div>
<p>
The method used to uninstall the LDAP authentication plugins
depends on how you installed them:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
If you installed the plugins at server startup using
<a class="link" href="server-options.html#option_mysqld_plugin-load-add">
<code class="option">
--plugin-load-add
</code>
</a>
options,
restart the server without those options.
</p>
</li>
<li class="listitem">
<p>
If you installed the plugins at runtime using
<a class="link" href="install-plugin.html" title="15.7.4.4 INSTALL PLUGIN Statement">
<code class="literal">
INSTALL PLUGIN
</code>
</a>
, they remain
installed across server restarts. To uninstall them, use
<a class="link" href="uninstall-plugin.html" title="15.7.4.6 UNINSTALL PLUGIN Statement">
<code class="literal">
UNINSTALL PLUGIN
</code>
</a>
:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa48573854"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">UNINSTALL</span> <span class="token keyword">PLUGIN</span> authentication_ldap_simple<span class="token punctuation">;</span>
<span class="token keyword">UNINSTALL</span> <span class="token keyword">PLUGIN</span> authentication_ldap_sasl<span class="token punctuation">;</span></code></pre>
</div>
</li>
</ul>
</div>
<p>
In addition, remove from your
<code class="filename">
my.cnf
</code>
file
any startup options that set LDAP plugin-related system
variables. If you used
<a class="link" href="set-variable.html" title="15.7.6.1 SET Syntax for Variable Assignment">
<code class="literal">
SET
PERSIST
</code>
</a>
to persist LDAP system variables, use
<a class="link" href="reset-persist.html" title="15.7.8.7 RESET PERSIST Statement">
<code class="literal">
RESET PERSIST
</code>
</a>
to remove the
settings.
</p>
</div>
<div class="simplesect">
<div class="titlepage">
<div>
<div class="simple">
<h5 class="title">
<a name="ldap-pluggable-authentication-ldap-conf">
</a>
LDAP Pluggable Authentication and ldap.conf
</h5>
</div>
</div>
</div>
<a class="indexterm" name="idm46045245205504">
</a>
<a class="indexterm" name="idm46045245204464">
</a>
<p>
For installations that use OpenLDAP, the
<code class="filename">
ldap.conf
</code>
file provides global defaults
for LDAP clients. Options can be set in this file to affect
LDAP clients, including the LDAP authentication plugins.
OpenLDAP uses configuration options in this order of
precedence:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
Configuration specified by the LDAP client.
</p>
</li>
<li class="listitem">
<p>
Configuration specified in the
<code class="filename">
ldap.conf
</code>
file. To disable use of
this file, set the
<code class="literal">
LDAPNOINIT
</code>
environment variable.
</p>
<a class="indexterm" name="idm46045245198208">
</a>
<a class="indexterm" name="idm46045245197120">
</a>
</li>
<li class="listitem">
<p>
OpenLDAP library built-in defaults.
</p>
</li>
</ul>
</div>
<p>
If the library defaults or
<code class="filename">
ldap.conf
</code>
values do not yield appropriate option values, an LDAP
authentication plugin may be able to set related variables to
affect the LDAP configuration directly. For example, LDAP
plugins can override
<code class="filename">
ldap.conf
</code>
for
parameters such as these:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
TLS configuration: System variables are available to
enable TLS and control CA configuration, such as
<a class="link" href="pluggable-authentication-system-variables.html#sysvar_authentication_ldap_simple_tls">
<code class="literal">
authentication_ldap_simple_tls
</code>
</a>
and
<a class="link" href="pluggable-authentication-system-variables.html#sysvar_authentication_ldap_simple_ca_path">
<code class="literal">
authentication_ldap_simple_ca_path
</code>
</a>
for simple LDAP authentication, and
<a class="link" href="pluggable-authentication-system-variables.html#sysvar_authentication_ldap_sasl_tls">
<code class="literal">
authentication_ldap_sasl_tls
</code>
</a>
and
<a class="link" href="pluggable-authentication-system-variables.html#sysvar_authentication_ldap_sasl_ca_path">
<code class="literal">
authentication_ldap_sasl_ca_path
</code>
</a>
for SASL LDAP authentication.
</p>
</li>
<li class="listitem">
<p>
LDAP referral. See
<a class="xref" href="ldap-pluggable-authentication.html#ldap-pluggable-authentication-ldap-referral" title="LDAP Search Referral">
LDAP Search Referral
</a>
.
</p>
</li>
</ul>
</div>
<p>
For more information about
<code class="filename">
ldap.conf
</code>
consult the
<code class="literal">
ldap.conf(5)
</code>
man page.
</p>
</div>
<div class="simplesect">
<div class="titlepage">
<div>
<div class="simple">
<h5 class="title">
<a name="ldap-pluggable-authentication-timeouts">
</a>
Setting Timeouts for LDAP Pluggable Authentication
</h5>
</div>
</div>
</div>
<p>
For MySQL accounts to connect to a MySQL server using LDAP
pluggable authentication, the LDAP server must be available
and operational. The interaction between the MySQL and LDAP
servers involves two steps. First, the MySQL server
establishes a connection to the LDAP server over TCP. Second,
the MySQL server sends an LDAP binding request over the
connection to the LDAP server and waits for a reply before
authenticating the account. If either step fails, the MySQL
account cannot connect to the MySQL server.
</p>
<p>
Short-duration timeouts that supersede a host system's
timeout values are applied to both the connection and response
steps by default. In all cases, the account user receives
notification that their attempt to connect to MySQL is denied
if the timeout expires. Client-side and server-side logging
can provide additional information. On the client side, set
the following environmental variable to elevate the detail
level and then restart MySQL client:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-ini"><div class="docs-select-all right" id="sa34831305"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-ini"><span class="token constant">AUTHENTICATION_LDAP_CLIENT_LOG</span><span class="token attr-value"><span class="token punctuation">=</span>5</span>
export AUTHENTICATION_LDAP_CLIENT_LOG</code></pre>
</div>
<p>
The following system variables support default timeouts for
SASL-based and simple LDAP authentication on Linux platforms
only.
</p>
<div class="table">
<a name="idm46045245177536">
</a>
<p class="title">
<b>
Table 8.22 System variables for SASL-based and simple LDAP Authentication
</b>
</p>
<div class="table-contents">
<table summary="System variables used for simple and SASL-based LDAP password authentication.">
<colgroup>
<col style="width: 75%"/>
<col style="width: 25%"/>
</colgroup>
<thead>
<tr>
<th>
System Variable Name
</th>
<th>
Default Timeout Value
</th>
</tr>
</thead>
<tbody>
<tr>
<td>
<a class="link" href="pluggable-authentication-system-variables.html#sysvar_authentication_ldap_sasl_connect_timeout">
<code class="literal">
authentication_ldap_sasl_connect_timeout
</code>
</a>
</td>
<td>
30 seconds
</td>
</tr>
<tr>
<td>
<a class="link" href="pluggable-authentication-system-variables.html#sysvar_authentication_ldap_sasl_response_timeout">
<code class="literal">
authentication_ldap_sasl_response_timeout
</code>
</a>
</td>
<td>
30 seconds
</td>
</tr>
<tr>
<td>
<a class="link" href="pluggable-authentication-system-variables.html#sysvar_authentication_ldap_simple_connect_timeout">
<code class="literal">
authentication_ldap_simple_connect_timeout
</code>
</a>
</td>
<td>
30 seconds
</td>
</tr>
<tr>
<td>
<a class="link" href="pluggable-authentication-system-variables.html#sysvar_authentication_ldap_simple_response_timeout">
<code class="literal">
authentication_ldap_simple_response_timeout
</code>
</a>
</td>
<td>
30 seconds
</td>
</tr>
</tbody>
</table>
</div>
</div>
<br class="table-break"/>
<p>
Timeout values for LDAP authentication are adjustable at
server startup and at runtime. If you set a timeout to zero
using one of these variables, you effectively disengage it and
MySQL server reverts to using the host system's default
timeout.
</p>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Note
</div>
<p>
Under the following combination of conditions, the actual
wait time of the
<a class="link" href="pluggable-authentication-system-variables.html#sysvar_authentication_ldap_sasl_connect_timeout">
<code class="literal">
authentication_ldap_sasl_connect_timeout
</code>
</a>
setting doubles because (internally) the server must invoke
the TCP connection twice:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
The LDAP server is offline.
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="pluggable-authentication-system-variables.html#sysvar_authentication_ldap_sasl_connect_timeout">
<code class="literal">
authentication_ldap_sasl_connect_timeout
</code>
</a>
has a value greater than zero.
</p>
</li>
<li class="listitem">
<p>
Connection pooling is in use (specifically, the
<a class="link" href="pluggable-authentication-system-variables.html#sysvar_authentication_ldap_sasl_max_pool_size">
<code class="literal">
authentication_ldap_sasl_max_pool_size
</code>
</a>
system variable has a value greater than zero, which
enables pooling).
</p>
</li>
</ul>
</div>
</div>
</div>
<div class="simplesect">
<div class="titlepage">
<div>
<div class="simple">
<h5 class="title">
<a name="ldap-pluggable-authentication-usage">
</a>
Using LDAP Pluggable Authentication
</h5>
</div>
</div>
</div>
<p>
This section describes how to enable MySQL accounts to connect
to the MySQL server using LDAP pluggable authentication. It is
assumed that the server is running with the appropriate
server-side plugins enabled, as described in
<a class="xref" href="ldap-pluggable-authentication.html#ldap-pluggable-authentication-installation" title="Installing LDAP Pluggable Authentication">
Installing LDAP Pluggable Authentication
</a>
,
and that the appropriate client-side plugins are available on
the client host.
</p>
<p>
This section does not describe LDAP configuration or
administration. You are assumed to be familiar with those
topics.
</p>
<p>
The two server-side LDAP plugins each work with a specific
client-side plugin:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
The server-side
<code class="literal">
authentication_ldap_simple
</code>
plugin
performs simple LDAP authentication. For connections by
accounts that use this plugin, client programs use the
client-side
<code class="literal">
mysql_clear_password
</code>
plugin, which sends the password to the server as
cleartext. No password hashing or encryption is used, so a
secure connection between the MySQL client and server is
recommended to prevent password exposure.
</p>
</li>
<li class="listitem">
<p>
The server-side
<code class="literal">
authentication_ldap_sasl
</code>
plugin
performs SASL-based LDAP authentication. For connections
by accounts that use this plugin, client programs use the
client-side
<code class="literal">
authentication_ldap_sasl_client
</code>
plugin.
The client-side and server-side SASL LDAP plugins use SASL
messages for secure transmission of credentials within the
LDAP protocol, to avoid sending the cleartext password
between the MySQL client and server.
</p>
</li>
</ul>
</div>
<p>
Overall requirements for LDAP authentication of MySQL users:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
There must be an LDAP directory entry for each user to be
authenticated.
</p>
</li>
<li class="listitem">
<p>
There must be a MySQL user account that specifies a
server-side LDAP authentication plugin and optionally
names the associated LDAP user distinguished name (DN).
(To associate an LDAP user DN with a MySQL account,
include a
<code class="literal">
BY
</code>
clause in the
<a class="link" href="create-user.html" title="15.7.1.3 CREATE USER Statement">
<code class="literal">
CREATE USER
</code>
</a>
statement that
creates the account.) If an account names no LDAP string,
LDAP authentication uses the user name specified by the
client to find the LDAP entry.
</p>
</li>
<li class="listitem">
<p>
Client programs connect using the connection method
appropriate for the server-side authentication plugin the
MySQL account uses. For LDAP authentication, connections
require the MySQL user name and LDAP password. In
addition, for accounts that use the server-side
<code class="literal">
authentication_ldap_simple
</code>
plugin,
invoke client programs with the
<code class="option">
--enable-cleartext-plugin
</code>
option to
enable the client-side
<code class="literal">
mysql_clear_password
</code>
plugin.
</p>
</li>
</ul>
</div>
<p>
The instructions here assume the following scenario:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
MySQL users
<code class="literal">
betsy
</code>
and
<code class="literal">
boris
</code>
authenticate to the LDAP entries
for
<code class="literal">
betsy_ldap
</code>
and
<code class="literal">
boris_ldap
</code>
, respectively. (It is not
necessary that the MySQL and LDAP user names differ. The
use of different names in this discussion helps clarify
whether an operation context is MySQL or LDAP.)
</p>
</li>
<li class="listitem">
<p>
LDAP entries use the
<code class="literal">
uid
</code>
attribute to
specify user names. This may vary depending on LDAP
server. Some LDAP servers use the
<code class="literal">
cn
</code>
attribute for user names rather than
<code class="literal">
uid
</code>
. To change the attribute, modify
the
<a class="link" href="pluggable-authentication-system-variables.html#sysvar_authentication_ldap_simple_user_search_attr">
<code class="literal">
authentication_ldap_simple_user_search_attr
</code>
</a>
or
<a class="link" href="pluggable-authentication-system-variables.html#sysvar_authentication_ldap_sasl_user_search_attr">
<code class="literal">
authentication_ldap_sasl_user_search_attr
</code>
</a>
system variable appropriately.
</p>
</li>
<li class="listitem">
<p>
These LDAP entries are available in the directory managed
by the LDAP server, to provide distinguished name values
that uniquely identify each user:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-ini"><div class="docs-select-all right" id="sa76721930"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-ini"><span class="token constant">uid</span><span class="token attr-value"><span class="token punctuation">=</span>betsy_ldap,ou=People,dc=example,dc=com</span>
<span class="token constant">uid</span><span class="token attr-value"><span class="token punctuation">=</span>boris_ldap,ou=People,dc=example,dc=com</span></code></pre>
</div>
</li>
<li class="listitem">
<p>
<a class="link" href="create-user.html" title="15.7.1.3 CREATE USER Statement">
<code class="literal">
CREATE USER
</code>
</a>
statements that
create MySQL accounts name an LDAP user in the
<code class="literal">
BY
</code>
clause, to indicate which LDAP entry
the MySQL account authenticates against.
</p>
</li>
</ul>
</div>
<p>
The instructions for setting up an account that uses LDAP
authentication depend on which server-side LDAP plugin is
used. The following sections describe several usage scenarios.
</p>
</div>
<div class="simplesect">
<div class="titlepage">
<div>
<div class="simple">
<h5 class="title">
<a name="ldap-pluggable-authentication-usage-simple">
</a>
Simple LDAP Authentication (Without Proxying)
</h5>
</div>
</div>
</div>
<p>
The procedure outlined in this section requires that
<a class="link" href="pluggable-authentication-system-variables.html#sysvar_authentication_ldap_simple_group_search_attr">
<code class="literal">
authentication_ldap_simple_group_search_attr
</code>
</a>
be set to an empty string, like this:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-sql"><div class="docs-select-all right" id="sa81538395"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">SET</span> <span class="token keyword">GLOBAL</span><span class="token punctuation">.</span>authentication_ldap_simple_group_search_attr<span class="token operator">=</span><span class="token string">''</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
Otherwise, proxying is used by default.
</p>
<p>
To set up a MySQL account for simple LDAP authentication, use
a
<a class="link" href="create-user.html" title="15.7.1.3 CREATE USER Statement">
<code class="literal">
CREATE USER
</code>
</a>
statement to
specify the
<code class="literal">
authentication_ldap_simple
</code>
plugin, optionally including the LDAP user distinguished name
(DN), as shown here:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa270559"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">CREATE</span> <span class="token keyword">USER</span> <span class="token keyword"><em class="replaceable">user</em></span>
<span class="token keyword">IDENTIFIED</span> <span class="token keyword">WITH</span> authentication_ldap_simple
<span class="token punctuation">[</span><span class="token keyword">BY</span> <span class="token string">'<em class="replaceable">LDAP user DN</em>'</span><span class="token punctuation">]</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
Suppose that MySQL user
<code class="literal">
betsy
</code>
has this
entry in the LDAP directory:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-ini"><div class="docs-select-all right" id="sa78001596"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-ini"><span class="token constant">uid</span><span class="token attr-value"><span class="token punctuation">=</span>betsy_ldap,ou=People,dc=example,dc=com</span></code></pre>
</div>
<p>
Then the statement to create the MySQL account for
<code class="literal">
betsy
</code>
looks like this:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa93057826"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">CREATE</span> <span class="token keyword">USER</span> <span class="token string">'betsy'</span>@<span class="token string">'localhost'</span>
<span class="token keyword">IDENTIFIED</span> <span class="token keyword">WITH</span> authentication_ldap_simple
<span class="token keyword">AS</span> <span class="token string">'uid=betsy_ldap,ou=People,dc=example,dc=com'</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
The authentication string specified in the
<code class="literal">
BY
</code>
clause does not include the LDAP
password. That must be provided by the client user at connect
time.
</p>
<p>
Clients connect to the MySQL server by providing the MySQL
user name and LDAP password, and by enabling the client-side
<code class="literal">
mysql_clear_password
</code>
plugin:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-terminal"><div class="docs-select-all right" id="sa34116465"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal"><span class="token prompt">$> </span><span class="token command">mysql</span> <span class="token constant">--user</span><span class="token attr-value"><span class="token punctuation">=</span>betsy</span> <span class="token property">--password</span> <span class="token property">--enable-cleartext-plugin</span>
Enter password<span class="token punctuation">:</span> <em class="replaceable">betsy_ldap_password</em></code></pre>
</div>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Note
</div>
<p>
The client-side
<code class="literal">
mysql_clear_password
</code>
authentication plugin leaves the password untouched, so
client programs send it to the MySQL server as cleartext.
This enables the password to be passed as is to the LDAP
server. A cleartext password is necessary to use the
server-side LDAP library without SASL, but may be a security
problem in some configurations. These measures minimize the
risk:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
To make inadvertent use of the
<code class="literal">
mysql_clear_password
</code>
plugin less
likely, MySQL clients must explicitly enable it (for
example, with the
<code class="option">
--enable-cleartext-plugin
</code>
option). See
<a class="xref" href="cleartext-pluggable-authentication.html" title="8.4.1.4 Client-Side Cleartext Pluggable Authentication">
Section 8.4.1.4, “Client-Side Cleartext Pluggable Authentication”
</a>
.
</p>
</li>
<li class="listitem">
<p>
To avoid password exposure with the
<code class="literal">
mysql_clear_password
</code>
plugin enabled,
MySQL clients should connect to the MySQL server using
an encrypted connection. See
<a class="xref" href="using-encrypted-connections.html" title="8.3.1 Configuring MySQL to Use Encrypted Connections">
Section 8.3.1, “Configuring MySQL to Use Encrypted Connections”
</a>
.
</p>
</li>
</ul>
</div>
</div>
<p>
The authentication process occurs as follows:
</p>
<div class="orderedlist">
<ol class="orderedlist" type="1">
<li class="listitem">
<p>
The client-side plugin sends
<code class="literal">
betsy
</code>
and
<em class="replaceable">
<code>
betsy_password
</code>
</em>
as the client
user name and LDAP password to the MySQL server.
</p>
</li>
<li class="listitem">
<p>
The connection attempt matches the
<code class="literal">
'betsy'@'localhost'
</code>
account. The
server-side LDAP plugin finds that this account has an
authentication string of
<code class="literal">
'uid=betsy_ldap,ou=People,dc=example,dc=com'
</code>
to name the LDAP user DN. The plugin sends this string and
the LDAP password to the LDAP server.
</p>
</li>
<li class="listitem">
<p>
The LDAP server finds the LDAP entry for
<code class="literal">
betsy_ldap
</code>
and the password matches, so
LDAP authentication succeeds.
</p>
</li>
<li class="listitem">
<p>
The LDAP entry has no group attribute, so the server-side
plugin returns the client user name
(
<code class="literal">
betsy
</code>
) as the authenticated user. This
is the same user name supplied by the client, so no
proxying occurs and the client session uses the
<code class="literal">
'betsy'@'localhost'
</code>
account for
privilege checking.
</p>
</li>
</ol>
</div>
<p>
Had the
<a class="link" href="create-user.html" title="15.7.1.3 CREATE USER Statement">
<code class="literal">
CREATE USER
</code>
</a>
statement
contained no
<code class="literal">
BY
</code>
clause to specify the
<code class="literal">
betsy_ldap
</code>
LDAP distinguished name,
authentication attempts would use the user name provided by
the client (in this case,
<code class="literal">
betsy
</code>
). In the
absence of an LDAP entry for
<code class="literal">
betsy
</code>
,
authentication would fail.
</p>
</div>
<div class="simplesect">
<div class="titlepage">
<div>
<div class="simple">
<h5 class="title">
<a name="ldap-pluggable-authentication-usage-sasl">
</a>
SASL-Based LDAP Authentication (Without Proxying)
</h5>
</div>
</div>
</div>
<p>
The procedure outlined in this section requires that
<a class="link" href="pluggable-authentication-system-variables.html#sysvar_authentication_ldap_sasl_group_search_attr">
<code class="literal">
authentication_ldap_sasl_group_search_attr
</code>
</a>
be set to an empty string, like this:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-sql"><div class="docs-select-all right" id="sa95433871"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">SET</span> <span class="token keyword">GLOBAL</span><span class="token punctuation">.</span>authentication_ldap_sasl_group_search_attr<span class="token operator">=</span><span class="token string">''</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
Otherwise, proxying is used by default.
</p>
<p>
To set up a MySQL account for SALS LDAP authentication, use a
<a class="link" href="create-user.html" title="15.7.1.3 CREATE USER Statement">
<code class="literal">
CREATE USER
</code>
</a>
statement to
specify the
<code class="literal">
authentication_ldap_sasl
</code>
plugin, optionally including the LDAP user distinguished name
(DN), as shown here:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa36201370"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">CREATE</span> <span class="token keyword">USER</span> <span class="token keyword"><em class="replaceable">user</em></span>
<span class="token keyword">IDENTIFIED</span> <span class="token keyword">WITH</span> authentication_ldap_sasl
<span class="token punctuation">[</span><span class="token keyword">BY</span> <span class="token string">'<em class="replaceable">LDAP user DN</em>'</span><span class="token punctuation">]</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
Suppose that MySQL user
<code class="literal">
boris
</code>
has this
entry in the LDAP directory:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-ini"><div class="docs-select-all right" id="sa85409826"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-ini"><span class="token constant">uid</span><span class="token attr-value"><span class="token punctuation">=</span>boris_ldap,ou=People,dc=example,dc=com</span></code></pre>
</div>
<p>
Then the statement to create the MySQL account for
<code class="literal">
boris
</code>
looks like this:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa37646472"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">CREATE</span> <span class="token keyword">USER</span> <span class="token string">'boris'</span>@<span class="token string">'localhost'</span>
<span class="token keyword">IDENTIFIED</span> <span class="token keyword">WITH</span> authentication_ldap_sasl
<span class="token keyword">AS</span> <span class="token string">'uid=boris_ldap,ou=People,dc=example,dc=com'</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
The authentication string specified in the
<code class="literal">
BY
</code>
clause does not include the LDAP
password. That must be provided by the client user at connect
time.
</p>
<p>
Clients connect to the MySQL server by providing the MySQL
user name and LDAP password:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-terminal"><div class="docs-select-all right" id="sa96294778"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal"><span class="token prompt">$> </span><span class="token command">mysql</span> <span class="token constant">--user</span><span class="token attr-value"><span class="token punctuation">=</span>boris</span> <span class="token property">--password</span>
Enter password<span class="token punctuation">:</span> <em class="replaceable">boris_ldap_password</em></code></pre>
</div>
<p>
For the server-side
<code class="literal">
authentication_ldap_sasl
</code>
plugin, clients
use the client-side
<code class="literal">
authentication_ldap_sasl_client
</code>
plugin. If
a client program does not find the client-side plugin, specify
a
<a class="link" href="connection-options.html#option_general_plugin-dir">
<code class="option">
--plugin-dir
</code>
</a>
option that
names the directory where the plugin library file is
installed.
</p>
<p>
The authentication process for
<code class="literal">
boris
</code>
is
similar to that previously described for
<code class="literal">
betsy
</code>
with simple LDAP authentication,
except that the client-side and server-side SASL LDAP plugins
use SASL messages for secure transmission of credentials
within the LDAP protocol, to avoid sending the cleartext
password between the MySQL client and server.
</p>
</div>
<div class="simplesect">
<div class="titlepage">
<div>
<div class="simple">
<h5 class="title">
<a name="ldap-pluggable-authentication-usage-proxying">
</a>
LDAP Authentication with Proxying
</h5>
</div>
</div>
</div>
<a class="indexterm" name="idm46045245051024">
</a>
<p>
LDAP authentication plugins support proxying, enabling a user
to connect to the MySQL server as one user but assume the
privileges of a different user. This section describes basic
LDAP plugin proxy support. The LDAP plugins also support
specification of group preference and proxy user mapping; see
<a class="xref" href="ldap-pluggable-authentication.html#ldap-pluggable-authentication-usage-group-mapping" title="LDAP Authentication Group Preference and Mapping Specification">
LDAP Authentication Group Preference and Mapping Specification
</a>
.
</p>
<p>
The proxying implementation described here is based on use of
LDAP group attribute values to map connecting MySQL users who
authenticate using LDAP onto other MySQL accounts that define
different sets of privileges. Users do not connect directly
through the accounts that define the privileges. Instead, they
connect through a default proxy account authenticated with
LDAP, such that all external logins are mapped to the proxied
MySQL accounts that hold the privileges. Any user who connects
using the proxy account is mapped to one of those proxied
MySQL accounts, the privileges for which determine the
database operations permitted to the external user.
</p>
<p>
The instructions here assume the following scenario:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
LDAP entries use the
<code class="literal">
uid
</code>
and
<code class="literal">
cn
</code>
attributes to specify user name and
group values, respectively. To use different user and
group attribute names, set the appropriate plugin-specific
system variables:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
For the
<code class="literal">
authentication_ldap_simple
</code>
plugin: Set
<a class="link" href="pluggable-authentication-system-variables.html#sysvar_authentication_ldap_simple_user_search_attr">
<code class="literal">
authentication_ldap_simple_user_search_attr
</code>
</a>
and
<a class="link" href="pluggable-authentication-system-variables.html#sysvar_authentication_ldap_simple_group_search_attr">
<code class="literal">
authentication_ldap_simple_group_search_attr
</code>
</a>
.
</p>
</li>
<li class="listitem">
<p>
For the
<code class="literal">
authentication_ldap_sasl
</code>
plugin: Set
<a class="link" href="pluggable-authentication-system-variables.html#sysvar_authentication_ldap_sasl_user_search_attr">
<code class="literal">
authentication_ldap_sasl_user_search_attr
</code>
</a>
and
<a class="link" href="pluggable-authentication-system-variables.html#sysvar_authentication_ldap_sasl_group_search_attr">
<code class="literal">
authentication_ldap_sasl_group_search_attr
</code>
</a>
.
</p>
</li>
</ul>
</div>
</li>
<li class="listitem">
<p>
These LDAP entries are available in the directory managed
by the LDAP server, to provide distinguished name values
that uniquely identify each user:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-ini"><div class="docs-select-all right" id="sa18055174"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-ini"><span class="token constant">uid</span><span class="token attr-value"><span class="token punctuation">=</span>basha,ou=People,dc=example,dc=com,cn=accounting</span>
<span class="token constant">uid</span><span class="token attr-value"><span class="token punctuation">=</span>basil,ou=People,dc=example,dc=com,cn=front_office</span></code></pre>
</div>
<p>
At connect time, the group attribute values become the
authenticated user names, so they name the
<code class="literal">
accounting
</code>
and
<code class="literal">
front_office
</code>
proxied accounts.
</p>
</li>
<li class="listitem">
<p>
The examples assume use of SASL LDAP authentication. Make
the appropriate adjustments for simple LDAP
authentication.
</p>
</li>
</ul>
</div>
<p>
Create the default proxy MySQL account:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa82514406"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">CREATE</span> <span class="token keyword">USER</span> <span class="token string">''</span>@<span class="token string">'%'</span>
<span class="token keyword">IDENTIFIED</span> <span class="token keyword">WITH</span> authentication_ldap_sasl<span class="token punctuation">;</span></code></pre>
</div>
<p>
The proxy account definition has no
<code class="literal">
AS
'
<em class="replaceable">
<code>
auth_string
</code>
</em>
'
</code>
clause to
name an LDAP user DN. Thus:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
When a client connects, the client user name becomes the
LDAP user name to search for.
</p>
</li>
<li class="listitem">
<p>
The matching LDAP entry is expected to include a group
attribute naming the proxied MySQL account that defines
the privileges the client should have.
</p>
</li>
</ul>
</div>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Note
</div>
<p>
If your MySQL installation has anonymous users, they might
conflict with the default proxy user. For more information
about this issue, and ways of dealing with it, see
<a class="xref" href="proxy-users.html#proxy-users-conflicts" title="Default Proxy User and Anonymous User Conflicts">
Default Proxy User and Anonymous User Conflicts
</a>
.
</p>
</div>
<p>
Create the proxied accounts and grant to each one the
privileges it should have:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa16503762"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">CREATE</span> <span class="token keyword">USER</span> <span class="token string">'accounting'</span>@<span class="token string">'localhost'</span>
<span class="token keyword">IDENTIFIED</span> <span class="token keyword">WITH</span> mysql_no_login<span class="token punctuation">;</span>
<span class="token keyword">CREATE</span> <span class="token keyword">USER</span> <span class="token string">'front_office'</span>@<span class="token string">'localhost'</span>
<span class="token keyword">IDENTIFIED</span> <span class="token keyword">WITH</span> mysql_no_login<span class="token punctuation">;</span>
<span class="token keyword">GRANT</span> <span class="token keyword">ALL</span> <span class="token keyword">PRIVILEGES</span>
<span class="token keyword">ON</span> accountingdb<span class="token punctuation">.</span><span class="token operator">*</span>
<span class="token keyword">TO</span> <span class="token string">'accounting'</span>@<span class="token string">'localhost'</span><span class="token punctuation">;</span>
<span class="token keyword">GRANT</span> <span class="token keyword">ALL</span> <span class="token keyword">PRIVILEGES</span>
<span class="token keyword">ON</span> frontdb<span class="token punctuation">.</span><span class="token operator">*</span>
<span class="token keyword">TO</span> <span class="token string">'front_office'</span>@<span class="token string">'localhost'</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
The proxied accounts use the
<code class="literal">
mysql_no_login
</code>
authentication plugin to prevent clients from using the
accounts to log in directly to the MySQL server. Instead,
users who authenticate using LDAP are expected to use the
default
<code class="literal">
''@'%'
</code>
proxy account. (This assumes
that the
<code class="literal">
mysql_no_login
</code>
plugin is
installed. For instructions, see
<a class="xref" href="no-login-pluggable-authentication.html" title="8.4.1.9 No-Login Pluggable Authentication">
Section 8.4.1.9, “No-Login Pluggable Authentication”
</a>
.) For
alternative methods of protecting proxied accounts against
direct use, see
<a class="xref" href="proxy-users.html#preventing-proxied-account-direct-login" title="Preventing Direct Login to Proxied Accounts">
Preventing Direct Login to Proxied Accounts
</a>
.
</p>
<p>
Grant to the proxy account the
<a class="link" href="privileges-provided.html#priv_proxy">
<code class="literal">
PROXY
</code>
</a>
privilege for each
proxied account:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa58011275"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">GRANT</span> <span class="token keyword">PROXY</span>
<span class="token keyword">ON</span> <span class="token string">'accounting'</span>@<span class="token string">'localhost'</span>
<span class="token keyword">TO</span> <span class="token string">''</span>@<span class="token string">'%'</span><span class="token punctuation">;</span>
<span class="token keyword">GRANT</span> <span class="token keyword">PROXY</span>
<span class="token keyword">ON</span> <span class="token string">'front_office'</span>@<span class="token string">'localhost'</span>
<span class="token keyword">TO</span> <span class="token string">''</span>@<span class="token string">'%'</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
Use the
<a class="link" href="mysql.html" title="6.5.1 mysql — The MySQL Command-Line Client">
<span class="command">
<strong>
mysql
</strong>
</span>
</a>
command-line client to
connect to the MySQL server as
<code class="literal">
basha
</code>
.
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-terminal"><div class="docs-select-all right" id="sa91662328"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal"><span class="token prompt">$> </span><span class="token command">mysql</span> <span class="token constant">--user</span><span class="token attr-value"><span class="token punctuation">=</span>basha</span> <span class="token property">--password</span>
Enter password<span class="token punctuation">:</span> <em class="replaceable">basha_password</em> <span class="token punctuation"></span><em class="replaceable"><span class="token punctuation">(</span>basha LDAP password<span class="token punctuation">)</span></em><span class="token punctuation"></span></code></pre>
</div>
<p>
Authentication occurs as follows:
</p>
<div class="orderedlist">
<ol class="orderedlist" type="1">
<li class="listitem">
<p>
The server authenticates the connection using the default
<code class="literal">
''@'%'
</code>
proxy account, for client user
<code class="literal">
basha
</code>
.
</p>
</li>
<li class="listitem">
<p>
The matching LDAP entry is:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-ini"><div class="docs-select-all right" id="sa21691612"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-ini"><span class="token constant">uid</span><span class="token attr-value"><span class="token punctuation">=</span>basha,ou=People,dc=example,dc=com,cn=accounting</span></code></pre>
</div>
</li>
<li class="listitem">
<p>
The matching LDAP entry has group attribute
<code class="literal">
cn=accounting
</code>
, so
<code class="literal">
accounting
</code>
becomes the authenticated
proxied user.
</p>
</li>
<li class="listitem">
<p>
The authenticated user differs from the client user name
<code class="literal">
basha
</code>
, with the result that
<code class="literal">
basha
</code>
is treated as a proxy for
<code class="literal">
accounting
</code>
, and
<code class="literal">
basha
</code>
assumes the privileges of the
proxied
<code class="literal">
accounting
</code>
account. The
following query returns output as shown:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa89426664"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">USER</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">,</span> <span class="token function">CURRENT_USER</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">,</span> <span class="token variable">@@proxy_user</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> USER() <span class="token punctuation">|</span> CURRENT_USER() <span class="token punctuation">|</span> @@proxy_user <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> basha@localhost <span class="token punctuation">|</span> accounting@localhost <span class="token punctuation">|</span> ''@'%' <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span></code></pre>
</div>
</li>
</ol>
</div>
<p>
This demonstrates that
<code class="literal">
basha
</code>
uses the
privileges granted to the proxied
<code class="literal">
accounting
</code>
MySQL account, and that proxying
occurs through the default proxy user account.
</p>
<p>
Now connect as
<code class="literal">
basil
</code>
instead:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-terminal"><div class="docs-select-all right" id="sa75469793"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal"><span class="token prompt">$> </span><span class="token command">mysql</span> <span class="token constant">--user</span><span class="token attr-value"><span class="token punctuation">=</span>basil</span> <span class="token property">--password</span>
Enter password<span class="token punctuation">:</span> <em class="replaceable">basil_password</em> <span class="token punctuation"></span><em class="replaceable"><span class="token punctuation">(</span>basil LDAP password<span class="token punctuation">)</span></em><span class="token punctuation"></span></code></pre>
</div>
<p>
The authentication process for
<code class="literal">
basil
</code>
is
similar to that previously described for
<code class="literal">
basha
</code>
:
</p>
<div class="orderedlist">
<ol class="orderedlist" type="1">
<li class="listitem">
<p>
The server authenticates the connection using the default
<code class="literal">
''@'%'
</code>
proxy account, for client user
<code class="literal">
basil
</code>
.
</p>
</li>
<li class="listitem">
<p>
The matching LDAP entry is:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-ini"><div class="docs-select-all right" id="sa70353229"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-ini"><span class="token constant">uid</span><span class="token attr-value"><span class="token punctuation">=</span>basil,ou=People,dc=example,dc=com,cn=front_office</span></code></pre>
</div>
</li>
<li class="listitem">
<p>
The matching LDAP entry has group attribute
<code class="literal">
cn=front_office
</code>
, so
<code class="literal">
front_office
</code>
becomes the authenticated
proxied user.
</p>
</li>
<li class="listitem">
<p>
The authenticated user differs from the client user name
<code class="literal">
basil
</code>
, with the result that
<code class="literal">
basil
</code>
is treated as a proxy for
<code class="literal">
front_office
</code>
, and
<code class="literal">
basil
</code>
assumes the privileges of the
proxied
<code class="literal">
front_office
</code>
account. The
following query returns output as shown:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa9596318"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">USER</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">,</span> <span class="token function">CURRENT_USER</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">,</span> <span class="token variable">@@proxy_user</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> USER() <span class="token punctuation">|</span> CURRENT_USER() <span class="token punctuation">|</span> @@proxy_user <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> basil@localhost <span class="token punctuation">|</span> front_office@localhost <span class="token punctuation">|</span> ''@'%' <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span></code></pre>
</div>
</li>
</ol>
</div>
<p>
This demonstrates that
<code class="literal">
basil
</code>
uses the
privileges granted to the proxied
<code class="literal">
front_office
</code>
MySQL account, and that
proxying occurs through the default proxy user account.
</p>
</div>
<div class="simplesect">
<div class="titlepage">
<div>
<div class="simple">
<h5 class="title">
<a name="ldap-pluggable-authentication-usage-group-mapping">
</a>
LDAP Authentication Group Preference and Mapping Specification
</h5>
</div>
</div>
</div>
<a class="indexterm" name="idm46045244968688">
</a>
<a class="indexterm" name="idm46045244967200">
</a>
<p>
As described in
<a class="xref" href="ldap-pluggable-authentication.html#ldap-pluggable-authentication-usage-proxying" title="LDAP Authentication with Proxying">
LDAP Authentication with Proxying
</a>
,
basic LDAP authentication proxying works by the principle that
the plugin uses the first group name returned by the LDAP
server as the MySQL proxied user account name. This simple
capability does not enable specifying any preference about
which group name to use if the LDAP server returns multiple
group names, or specifying any name other than the group name
as the proxied user name.
</p>
<p>
For MySQL accounts that use LDAP authentication, the
authentication string can specify the following information to
enable greater proxying flexibility:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
A list of groups in preference order, such that the plugin
uses the first group name in the list that matches a group
returned by the LDAP server.
</p>
</li>
<li class="listitem">
<p>
A mapping from group names to proxied user names, such
that a group name when matched can provide a specified
name to use as the proxied user. This provides an
alternative to using the group name as the proxied user.
</p>
</li>
</ul>
</div>
<p>
Consider the following MySQL proxy account definition:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa87018829"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">CREATE</span> <span class="token keyword">USER</span> <span class="token string">''</span>@<span class="token string">'%'</span>
<span class="token keyword">IDENTIFIED</span> <span class="token keyword">WITH</span> authentication_ldap_sasl
<span class="token keyword">AS</span> <span class="token string">'+ou=People,dc=example,dc=com#grp1=usera,grp2,grp3=userc'</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
The authentication string has a user DN suffix
<code class="literal">
ou=People,dc=example,dc=com
</code>
prefixed by the
<code class="literal">
+
</code>
character. Thus, as described in
<a class="xref" href="ldap-pluggable-authentication.html#ldap-pluggable-authentication-usage-user-dn-suffix" title="LDAP Authentication User DN Suffixes">
LDAP Authentication User DN Suffixes
</a>
,
the full user DN is constructed from the user DN suffix as
specified, plus the client user name as the
<code class="literal">
uid
</code>
attribute.
</p>
<p>
The remaining part of the authentication string begins with
<code class="literal">
#
</code>
, which signifies the beginning of group
preference and mapping information. This part of the
authentication string lists group names in the order
<code class="literal">
grp1
</code>
,
<code class="literal">
grp2
</code>
,
<code class="literal">
grp3
</code>
. The LDAP plugin compares that list
with the set of group names returned by the LDAP server,
looking in list order for a match against the returned names.
The plugin uses the first match, or if there is no match,
authentication fails.
</p>
<p>
Suppose that the LDAP server returns groups
<code class="literal">
grp3
</code>
,
<code class="literal">
grp2
</code>
, and
<code class="literal">
grp7
</code>
. The LDAP plugin uses
<code class="literal">
grp2
</code>
because it is the first group in the
authentication string that matches, even though it is not the
first group returned by the LDAP server. If the LDAP server
returns
<code class="literal">
grp4
</code>
,
<code class="literal">
grp2
</code>
, and
<code class="literal">
grp1
</code>
, the plugin uses
<code class="literal">
grp1
</code>
even though
<code class="literal">
grp2
</code>
also matches.
<code class="literal">
grp1
</code>
has a precedence higher
than
<code class="literal">
grp2
</code>
because it is listed earlier in
the authentication string.
</p>
<p>
Assuming that the plugin finds a group name match, it performs
mapping from that group name to the MySQL proxied user name,
if there is one. For the example proxy account, mapping occurs
as follows:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
If the matching group name is
<code class="literal">
grp1
</code>
or
<code class="literal">
grp3
</code>
, those are associated in the
authentication string with user names
<code class="literal">
usera
</code>
and
<code class="literal">
userc
</code>
,
respectively. The plugin uses the corresponding associated
user name as the proxied user name.
</p>
</li>
<li class="listitem">
<p>
If the matching group name is
<code class="literal">
grp2
</code>
,
there is no associated user name in the authentication
string. The plugin uses
<code class="literal">
grp2
</code>
as the
proxied user name.
</p>
</li>
</ul>
</div>
<p>
If the LDAP server returns a group in DN format, the LDAP
plugin parses the group DN to extract the group name from it.
</p>
<p>
To specify LDAP group preference and mapping information,
these principles apply:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
Begin the group preference and mapping part of the
authentication string with a
<code class="literal">
#
</code>
prefix
character.
</p>
</li>
<li class="listitem">
<p>
The group preference and mapping specification is a list
of one or more items, separated by commas. Each item has
the form
<code class="literal">
<em class="replaceable">
<code>
group_name
</code>
</em>
=
<em class="replaceable">
<code>
user_name
</code>
</em>
</code>
or
<em class="replaceable">
<code>
group_name
</code>
</em>
. Items should be
listed in group name preference order. For a group name
selected by the plugin as a match from set of group names
returned by the LDAP server, the two syntaxes differ in
effect as follows:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
For an item specified as
<code class="literal">
<em class="replaceable">
<code>
group_name
</code>
</em>
=
<em class="replaceable">
<code>
user_name
</code>
</em>
</code>
(with a user name), the group name maps to the user
name, which is used as the MySQL proxied user name.
</p>
</li>
<li class="listitem">
<p>
For an item specified as
<em class="replaceable">
<code>
group_name
</code>
</em>
(with no user
name), the group name is used as the MySQL proxied
user name.
</p>
</li>
</ul>
</div>
</li>
<li class="listitem">
<p>
To quote a group or user name that contains special
characters such as space, surround it by double quote
(
<code class="literal">
"
</code>
) characters. For example, if an item
has group and user names of
<code class="literal">
my group
name
</code>
and
<code class="literal">
my user name
</code>
, it
must be written in a group mapping using quotes:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-none"><div class="docs-select-all right" id="sa57655303"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-none">"my group name"="my user name"</code></pre>
</div>
<p>
If an item has group and user names of
<code class="literal">
my_group_name
</code>
and
<code class="literal">
my_user_name
</code>
(which contain no special
characters), it may but need not be written using quotes.
Any of the following are valid:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-none"><div class="docs-select-all right" id="sa33335711"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-none">my_group_name=my_user_name
my_group_name="my_user_name"
"my_group_name"=my_user_name
"my_group_name"="my_user_name"</code></pre>
</div>
</li>
<li class="listitem">
<p>
To escape a character, precede it by a backslash
(
<code class="literal">
\
</code>
). This is useful particularly to
include a literal double quote or backslash, which are
otherwise not included literally.
</p>
</li>
<li class="listitem">
<p>
A user DN need not be present in the authentication
string, but if present, it must precede the group
preference and mapping part. A user DN can be given as a
full user DN, or as a user DN suffix with a
<code class="literal">
+
</code>
prefix character. (See
<a class="xref" href="ldap-pluggable-authentication.html#ldap-pluggable-authentication-usage-user-dn-suffix" title="LDAP Authentication User DN Suffixes">
LDAP Authentication User DN Suffixes
</a>
.)
</p>
</li>
</ul>
</div>
</div>
<div class="simplesect">
<div class="titlepage">
<div>
<div class="simple">
<h5 class="title">
<a name="ldap-pluggable-authentication-usage-user-dn-suffix">
</a>
LDAP Authentication User DN Suffixes
</h5>
</div>
</div>
</div>
<p>
LDAP authentication plugins permit the authentication string
that provides user DN information to begin with a
<code class="literal">
+
</code>
prefix character:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
In the absence of a
<code class="literal">
+
</code>
character, the
authentication string value is treated as is without
modification.
</p>
</li>
<li class="listitem">
<p>
If the authentication string begins with
<code class="literal">
+
</code>
, the plugin constructs the full user
DN value from the user name sent by the client, together
with the DN specified in the authentication string (with
the
<code class="literal">
+
</code>
removed). In the constructed DN,
the client user name becomes the value of the attribute
that specifies LDAP user names. This is
<code class="literal">
uid
</code>
by default; to change the
attribute, modify the appropriate system variable
(
<a class="link" href="pluggable-authentication-system-variables.html#sysvar_authentication_ldap_simple_user_search_attr">
<code class="literal">
authentication_ldap_simple_user_search_attr
</code>
</a>
or
<a class="link" href="pluggable-authentication-system-variables.html#sysvar_authentication_ldap_sasl_user_search_attr">
<code class="literal">
authentication_ldap_sasl_user_search_attr
</code>
</a>
).
The authentication string is stored as given in the
<code class="literal">
mysql.user
</code>
system table, with the full
user DN constructed on the fly before authentication.
</p>
</li>
</ul>
</div>
<p>
This account authentication string does not have
<code class="literal">
+
</code>
at the beginning, so it is taken as the
full user DN:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa95230773"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">CREATE</span> <span class="token keyword">USER</span> <span class="token string">'baldwin'</span>
<span class="token keyword">IDENTIFIED</span> <span class="token keyword">WITH</span> authentication_ldap_simple
<span class="token keyword">AS</span> <span class="token string">'uid=admin,ou=People,dc=example,dc=com'</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
The client connects with the user name specified in the
account (
<code class="literal">
baldwin
</code>
). In this case, that name
is not used because the authentication string has no prefix
and thus fully specifies the user DN.
</p>
<p>
This account authentication string does have
<code class="literal">
+
</code>
at the beginning, so it is taken as just
part of the user DN:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa62080184"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">CREATE</span> <span class="token keyword">USER</span> <span class="token string">'accounting'</span>
<span class="token keyword">IDENTIFIED</span> <span class="token keyword">WITH</span> authentication_ldap_simple
<span class="token keyword">AS</span> <span class="token string">'+ou=People,dc=example,dc=com'</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
The client connects with the user name specified in the
account (
<code class="literal">
accounting
</code>
), which in this case is
used as the
<code class="literal">
uid
</code>
attribute together with the
authentication string to construct the user DN:
<code class="literal">
uid=accounting,ou=People,dc=example,dc=com
</code>
</p>
<p>
The accounts in the preceding examples have a nonempty user
name, so the client always connects to the MySQL server using
the same name as specified in the account definition. If an
account has an empty user name, such as the default anonymous
<code class="literal">
''@'%'
</code>
proxy account described in
<a class="xref" href="ldap-pluggable-authentication.html#ldap-pluggable-authentication-usage-proxying" title="LDAP Authentication with Proxying">
LDAP Authentication with Proxying
</a>
,
clients might connect to the MySQL server with varying user
names. But the principle is the same: If the authentication
string begins with
<code class="literal">
+
</code>
, the plugin uses the
user name sent by the client together with the authentication
string to construct the user DN.
</p>
</div>
<div class="simplesect">
<div class="titlepage">
<div>
<div class="simple">
<h5 class="title">
<a name="ldap-pluggable-authentication-auth-methods">
</a>
LDAP Authentication Methods
</h5>
</div>
</div>
</div>
<p>
The LDAP authentication plugins use a configurable
authentication method. The appropriate system variable and
available method choices are plugin-specific:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
For the
<code class="literal">
authentication_ldap_simple
</code>
plugin: Set the
<a class="link" href="pluggable-authentication-system-variables.html#sysvar_authentication_ldap_simple_auth_method_name">
<code class="literal">
authentication_ldap_simple_auth_method_name
</code>
</a>
system variable to configure the method. The permitted
choices are
<code class="literal">
SIMPLE
</code>
and
<code class="literal">
AD-FOREST
</code>
.
</p>
</li>
<li class="listitem">
<p>
For the
<code class="literal">
authentication_ldap_sasl
</code>
plugin: Set the
<a class="link" href="pluggable-authentication-system-variables.html#sysvar_authentication_ldap_sasl_auth_method_name">
<code class="literal">
authentication_ldap_sasl_auth_method_name
</code>
</a>
system variable to configure the method. The permitted
choices are
<code class="literal">
SCRAM-SHA-1
</code>
,
<code class="literal">
SCRAM-SHA-256
</code>
, and
<code class="literal">
GSSAPI
</code>
. (To determine which SASL LDAP
methods are actually available on the host system, check
the value of the
<a class="link" href="server-status-variables.html#statvar_Authentication_ldap_sasl_supported_methods">
<code class="literal">
Authentication_ldap_sasl_supported_methods
</code>
</a>
status variable.)
</p>
</li>
</ul>
</div>
<p>
See the system variable descriptions for information about
each permitted method. Also, depending on the method,
additional configuration may be needed, as described in the
following sections.
</p>
</div>
<div class="simplesect">
<div class="titlepage">
<div>
<div class="simple">
<h5 class="title">
<a name="ldap-pluggable-authentication-gssapi">
</a>
The GSSAPI/Kerberos Authentication Method
</h5>
</div>
</div>
</div>
<a class="indexterm" name="idm46045244876576">
</a>
<a class="indexterm" name="idm46045244875120">
</a>
<a class="indexterm" name="idm46045244873616">
</a>
<a class="indexterm" name="idm46045244872112">
</a>
<p>
Generic Security Service Application Program Interface
(GSSAPI) is a security abstraction interface. Kerberos is an
instance of a specific security protocol that can be used
through that abstract interface. Using GSSAPI, applications
authenticate to Kerberos to obtain service credentials, then
use those credentials in turn to enable secure access to other
services.
</p>
<p>
One such service is LDAP, which is used by the client-side and
server-side SASL LDAP authentication plugins. When the
<a class="link" href="pluggable-authentication-system-variables.html#sysvar_authentication_ldap_sasl_auth_method_name">
<code class="literal">
authentication_ldap_sasl_auth_method_name
</code>
</a>
system variable is set to
<code class="literal">
GSSAPI
</code>
, these
plugins use the GSSAPI/Kerberos authentication method. In this
case, the plugins communicate securely using Kerberos without
using LDAP messages directly. The server-side plugin then
communicates with the LDAP server to interpret LDAP
authentication messages and retrieve LDAP groups.
</p>
<p>
GSSAPI/Kerberos is supported as an LDAP authentication method
for MySQL servers and clients on Linux. It is useful in Linux
environments where applications have access to LDAP through
Microsoft Active Directory, which has Kerberos enabled by
default.
</p>
<p>
The following discussion provides information about the
configuration requirements for using the GSSAPI method.
Familiarity is assumed with Kerberos concepts and operation.
The following list briefly defines several common Kerberos
terms. You may also find the Glossary section of
<a class="ulink" href="https://tools.ietf.org/html/rfc4120" target="_blank">
RFC
4120
</a>
helpful.
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<a class="link" href="glossary.html#glos_principal" title="principal">
Principal
</a>
: A named
entity, such as a user or server.
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="glossary.html#glos_key_distribution_center" title="key distribution center">
KDC
</a>
:
The key distribution center, comprising the AS and TGS:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
<a class="link" href="glossary.html#glos_authentication_server" title="authentication server">
AS
</a>
:
The authentication server; provides the initial
ticket-granting ticket needed to obtain additional
tickets.
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="glossary.html#glos_ticket_granting_server" title="ticket-granting server">
TGS
</a>
:
The ticket-granting server; provides additional
tickets to Kerberos clients that possess a valid TGT.
</p>
</li>
</ul>
</div>
</li>
<li class="listitem">
<p>
<a class="link" href="glossary.html#glos_ticket_granting_ticket" title="ticket-granting ticket">
TGT
</a>
:
The ticket-granting ticket; presented to the TGS to obtain
service tickets for service access.
</p>
</li>
</ul>
</div>
<p>
LDAP authentication using Kerberos requires both a KDC server
and an LDAP server. This requirement can be satisfied in
different ways:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
Active Directory includes both servers, with Kerberos
authentication enabled by default in the Active Directory
LDAP server.
</p>
</li>
<li class="listitem">
<p>
OpenLDAP provides an LDAP server, but a separate KDC
server may be needed, with additional Kerberos setup
required.
</p>
</li>
</ul>
</div>
<p>
Kerberos must also be available on the client host. A client
contacts the AS using a password to obtain a TGT. The client
then uses the TGT to obtain access from the TGS to other
services, such as LDAP.
</p>
<p>
The following sections discuss the configuration steps to use
GSSAPI/Kerberos for SASL LDAP authentication in MySQL:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<a class="xref" href="ldap-pluggable-authentication.html#ldap-gssapi-kerberos-setup" title="Verify Kerberos and LDAP Availability">
Verify Kerberos and LDAP Availability
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="xref" href="ldap-pluggable-authentication.html#ldap-gssapi-ldap-setup" title="Configure the Server-Side SASL LDAP Authentication Plugin for GSSAPI/Kerberos">
Configure the Server-Side SASL LDAP Authentication Plugin for GSSAPI/Kerberos
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="xref" href="ldap-pluggable-authentication.html#ldap-gssapi-mysql-account-setup" title="Create a MySQL Account That Uses GSSAPI/Kerberos for LDAP Authentication">
Create a MySQL Account That Uses GSSAPI/Kerberos for LDAP Authentication
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="xref" href="ldap-pluggable-authentication.html#ldap-gssapi-mysql-client-usage" title="Use the MySQL Account to Connect to the MySQL Server">
Use the MySQL Account to Connect to the MySQL Server
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="xref" href="ldap-pluggable-authentication.html#ldap-gssapi-mysql-client-config-parameters" title="Client Configuration Parameters for LDAP Authentication">
Client Configuration Parameters for LDAP Authentication
</a>
</p>
</li>
</ul>
</div>
<h6>
<a name="ldap-gssapi-kerberos-setup">
</a>
Verify Kerberos and LDAP Availability
</h6>
<p>
The following example shows how to test availability of
Kerberos in Active Directory. The example makes these
assumptions:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
Active Directory is running on the host named
<code class="literal">
ldap_auth.example.com
</code>
with IP address
<code class="literal">
198.51.100.10
</code>
.
</p>
</li>
<li class="listitem">
<p>
MySQL-related Kerberos authentication and LDAP lookups use
the
<code class="literal">
MYSQL.LOCAL
</code>
domain.
</p>
</li>
<li class="listitem">
<p>
A principal named
<code class="literal">
[email protected]
</code>
is
registered with the KDC. (In later discussion, this
principal name is also associated with the MySQL account
that authenticates to the MySQL server using
GSSAPI/Kerberos.)
</p>
</li>
</ul>
</div>
<p>
With those assumptions satisfied, follow this procedure:
</p>
<div class="orderedlist">
<ol class="orderedlist" type="1">
<li class="listitem">
<p>
Verify that the Kerberos library is installed and
configured correctly in the operating system. For example,
to configure a
<code class="literal">
MYSQL.LOCAL
</code>
domain for
use during MySQL authentication, the
<code class="filename">
/etc/krb5.conf
</code>
Kerberos configuration
file should contain something like this:
</p>
<a class="indexterm" name="idm46045244832608">
</a>
<a class="indexterm" name="idm46045244831120">
</a>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-ini"><div class="docs-select-all right" id="sa44943597"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-ini"><span class="token selector">[realms]</span>
<span class="token constant"> MYSQL.LOCAL</span> <span class="token attr-value"><span class="token punctuation">=</span> {</span>
<span class="token constant"> kdc</span> <span class="token attr-value"><span class="token punctuation">=</span> ldap_auth.example.com</span>
<span class="token constant"> admin_server</span> <span class="token attr-value"><span class="token punctuation">=</span> ldap_auth.example.com</span>
<span class="token constant"> default_domain</span> <span class="token attr-value"><span class="token punctuation">=</span> MYSQL.LOCAL</span>
}</code></pre>
</div>
</li>
<li class="listitem">
<p>
You may need to add an entry to
<code class="filename">
/etc/hosts
</code>
for the server host:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-simple"><div class="docs-select-all right" id="sa73727839"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-simple">198<span class="token punctuation">.</span>51<span class="token punctuation">.</span>100<span class="token punctuation">.</span>10 ldap_auth ldap_auth<span class="token punctuation">.</span>example<span class="token punctuation">.</span>com</code></pre>
</div>
</li>
<li class="listitem">
<p>
Check whether Kerberos authentication works correctly:
</p>
<div class="orderedlist">
<ol class="orderedlist" type="a">
<li class="listitem">
<p>
Use
<span class="command">
<strong>
kinit
</strong>
</span>
to authenticate to
Kerberos:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-terminal"><div class="docs-select-all right" id="sa37747153"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal"><span class="token prompt">$> </span><span class="token command">kinit</span> bredon@MYSQL<span class="token punctuation">.</span>LOCAL
Password for bredon@MYSQL<span class="token punctuation">.</span>LOCAL<span class="token punctuation">:</span> <span class="token punctuation"></span><em class="replaceable"><span class="token punctuation">(</span>enter password here<span class="token punctuation">)</span></em><span class="token punctuation"></span></code></pre>
</div>
<p>
The command authenticates for the Kerberos principal
named
<code class="literal">
[email protected]
</code>
. Enter the
principal's password when the command prompts for
it. The KDC returns a TGT that is cached on the client
side for use by other Kerberos-aware applications.
</p>
</li>
<li class="listitem">
<p>
Use
<span class="command">
<strong>
klist
</strong>
</span>
to check whether the TGT
was obtained correctly. The output should be similar
to this:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-terminal"><div class="docs-select-all right" id="sa80166448"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal"><span class="token prompt">$> </span><span class="token command">klist</span>
Ticket cache<span class="token punctuation">:</span> FILE<span class="token punctuation">:</span>/tmp/krb5cc_244306
Default principal<span class="token punctuation">:</span> bredon@MYSQL<span class="token punctuation">.</span>LOCAL
Valid starting Expires Service principal
03/23/2021 08<span class="token punctuation">:</span>18<span class="token punctuation">:</span>33 03/23/2021 18<span class="token punctuation">:</span>18<span class="token punctuation">:</span>33 krbtgt/MYSQL<span class="token punctuation">.</span>LOCAL@MYSQL<span class="token punctuation">.</span>LOCAL</code></pre>
</div>
</li>
</ol>
</div>
</li>
<li class="listitem">
<p>
Check whether
<span class="command">
<strong>
ldapsearch
</strong>
</span>
works with the
Kerberos TGT using this command, which searches for users
in the
<code class="literal">
MYSQL.LOCAL
</code>
domain:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-terminal"><div class="docs-select-all right" id="sa81890148"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal">ldapsearch <span class="token property">-h</span> 198<span class="token punctuation">.</span>51<span class="token punctuation">.</span>100<span class="token punctuation">.</span>10 <span class="token property">-Y</span> GSSAPI <span class="token property">-b</span> <span class="token atrule">"dc=MYSQL,dc=LOCAL"</span></code></pre>
</div>
</li>
</ol>
</div>
<h6>
<a name="ldap-gssapi-ldap-setup">
</a>
Configure the Server-Side SASL LDAP Authentication Plugin for
GSSAPI/Kerberos
</h6>
<p>
Assuming that the LDAP server is accessible through Kerberos
as just described, configure the server-side SASL LDAP
authentication plugin to use the GSSAPI/Kerberos
authentication method. (For general LDAP plugin installation
information, see
<a class="xref" href="ldap-pluggable-authentication.html#ldap-pluggable-authentication-installation" title="Installing LDAP Pluggable Authentication">
Installing LDAP Pluggable Authentication
</a>
.)
Here is an example of plugin-related settings the server
<code class="filename">
my.cnf
</code>
file might contain:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-ini"><div class="docs-select-all right" id="sa9114135"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-ini"><span class="token selector">[mysqld]</span>
<span class="token constant">plugin-load-add</span><span class="token attr-value"><span class="token punctuation">=</span>authentication_ldap_sasl.so</span>
<span class="token constant">authentication_ldap_sasl_auth_method_name</span><span class="token attr-value"><span class="token punctuation">=</span>"GSSAPI"</span>
<span class="token constant">authentication_ldap_sasl_server_host</span><span class="token attr-value"><span class="token punctuation">=</span>198.51.100.10</span>
<span class="token constant">authentication_ldap_sasl_server_port</span><span class="token attr-value"><span class="token punctuation">=</span>389</span>
<span class="token constant">authentication_ldap_sasl_bind_root_dn</span><span class="token attr-value"><span class="token punctuation">=</span>"cn=admin,cn=users,dc=MYSQL,dc=LOCAL"</span>
<span class="token constant">authentication_ldap_sasl_bind_root_pwd</span><span class="token attr-value"><span class="token punctuation">=</span>"<em class="replaceable">password</em>"</span>
<span class="token constant">authentication_ldap_sasl_bind_base_dn</span><span class="token attr-value"><span class="token punctuation">=</span>"cn=users,dc=MYSQL,dc=LOCAL"</span>
<span class="token constant">authentication_ldap_sasl_user_search_attr</span><span class="token attr-value"><span class="token punctuation">=</span>"sAMAccountName"</span></code></pre>
</div>
<p>
Those option file settings configure the SASL LDAP plugin as
follows:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
The
<a class="link" href="server-options.html#option_mysqld_plugin-load-add">
<code class="option">
--plugin-load-add
</code>
</a>
option loads the plugin (adjust the
<code class="filename">
.so
</code>
suffix for your platform as
necessary). If you loaded the plugin previously using an
<a class="link" href="install-plugin.html" title="15.7.4.4 INSTALL PLUGIN Statement">
<code class="literal">
INSTALL PLUGIN
</code>
</a>
statement,
this option is unnecessary.
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="pluggable-authentication-system-variables.html#sysvar_authentication_ldap_sasl_auth_method_name">
<code class="literal">
authentication_ldap_sasl_auth_method_name
</code>
</a>
must be set to
<code class="literal">
GSSAPI
</code>
to use
GSSAPI/Kerberos as the SASL LDAP authentication method.
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="pluggable-authentication-system-variables.html#sysvar_authentication_ldap_sasl_server_host">
<code class="literal">
authentication_ldap_sasl_server_host
</code>
</a>
and
<a class="link" href="pluggable-authentication-system-variables.html#sysvar_authentication_ldap_sasl_server_port">
<code class="literal">
authentication_ldap_sasl_server_port
</code>
</a>
indicate the IP address and port number of the Active
Directory server host for authentication.
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="pluggable-authentication-system-variables.html#sysvar_authentication_ldap_sasl_bind_root_dn">
<code class="literal">
authentication_ldap_sasl_bind_root_dn
</code>
</a>
and
<a class="link" href="pluggable-authentication-system-variables.html#sysvar_authentication_ldap_sasl_bind_root_pwd">
<code class="literal">
authentication_ldap_sasl_bind_root_pwd
</code>
</a>
configure the root DN and password for group search
capability. This capability is required, but users may not
have privileges to search. In such cases, it is necessary
to provide root DN information:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
In the DN option value,
<code class="literal">
admin
</code>
should be the name of an administrative LDAP account
that has privileges to perform user searches.
</p>
</li>
<li class="listitem">
<p>
In the password option value,
<em class="replaceable">
<code>
password
</code>
</em>
should be the
<code class="literal">
admin
</code>
account password.
</p>
</li>
</ul>
</div>
</li>
<li class="listitem">
<p>
<a class="link" href="pluggable-authentication-system-variables.html#sysvar_authentication_ldap_sasl_bind_base_dn">
<code class="literal">
authentication_ldap_sasl_bind_base_dn
</code>
</a>
indicates the user DN base path, so that searches look for
users in the
<code class="literal">
MYSQL.LOCAL
</code>
domain.
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="pluggable-authentication-system-variables.html#sysvar_authentication_ldap_sasl_user_search_attr">
<code class="literal">
authentication_ldap_sasl_user_search_attr
</code>
</a>
specifies a standard Active Directory search attribute,
<code class="literal">
sAMAccountName
</code>
. This attribute is used
in searches to match logon names; attribute values are not
the same as the user DN values.
</p>
</li>
</ul>
</div>
<h6>
<a name="ldap-gssapi-mysql-account-setup">
</a>
Create a MySQL Account That Uses GSSAPI/Kerberos for LDAP Authentication
</h6>
<p>
MySQL authentication using the SASL LDAP authentication plugin
with the GSSAPI/Kerberos method is based on a user that is a
Kerberos principal. The following discussion uses a principal
named
<code class="literal">
[email protected]
</code>
as this user,
which must be registered in several places:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
The Kerberos administrator should register the user name
as a Kerberos principal. This name should include a domain
name. Clients use the principal name and password to
authenticate with Kerberos and obtain a TGT.
</p>
</li>
<li class="listitem">
<p>
The LDAP administrator should register the user name in an
LDAP entry. For example:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-none"><div class="docs-select-all right" id="sa38118371"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-none">uid=bredon,dc=MYSQL,dc=LOCAL</code></pre>
</div>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Note
</div>
<p>
In Active Directory (which uses Kerberos as the default
authentication method), creating a user creates both the
Kerberos principal and the LDAP entry.
</p>
</div>
</li>
<li class="listitem">
<p>
The MySQL DBA should create an account that has the
Kerberos principal name as the user name and that
authenticates using the SASL LDAP plugin.
</p>
</li>
</ul>
</div>
<p>
Assume that the Kerberos principal and LDAP entry have been
registered by the appropriate service administrators, and
that, as previously described in
<a class="xref" href="ldap-pluggable-authentication.html#ldap-pluggable-authentication-installation" title="Installing LDAP Pluggable Authentication">
Installing LDAP Pluggable Authentication
</a>
,
and
<a class="xref" href="ldap-pluggable-authentication.html#ldap-gssapi-ldap-setup" title="Configure the Server-Side SASL LDAP Authentication Plugin for GSSAPI/Kerberos">
Configure the Server-Side SASL LDAP Authentication Plugin for GSSAPI/Kerberos
</a>
, the MySQL server
has been started with appropriate configuration settings for
the server-side SASL LDAP plugin. The MySQL DBA then creates a
MySQL account that corresponds to the Kerberos principal name,
including the domain name.
</p>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Note
</div>
<p>
The SASL LDAP plugin uses a constant user DN for Kerberos
authentication and ignores any user DN configured from
MySQL. This has certain implications:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
For any MySQL account that uses GSSAPI/Kerberos
authentication, the authentication string in
<a class="link" href="create-user.html" title="15.7.1.3 CREATE USER Statement">
<code class="literal">
CREATE USER
</code>
</a>
or
<a class="link" href="alter-user.html" title="15.7.1.1 ALTER USER Statement">
<code class="literal">
ALTER USER
</code>
</a>
statements
should contain no user DN because it has no effect.
</p>
</li>
<li class="listitem">
<p>
Because the authentication string contains no user DN,
it should contain group mapping information, to enable
the user to be handled as a proxy user that is mapped
onto the desired proxied user. For information about
proxying with the LDAP authentication plugin, see
<a class="xref" href="ldap-pluggable-authentication.html#ldap-pluggable-authentication-usage-proxying" title="LDAP Authentication with Proxying">
LDAP Authentication with Proxying
</a>
.
</p>
</li>
</ul>
</div>
</div>
<p>
The following statements create a proxy user named
<code class="literal">
[email protected]
</code>
that assumes the
privileges of the proxied user named
<code class="literal">
proxied_krb_usr
</code>
. Other GSSAPI/Kerberos
users that should have the same privileges can similarly be
created as proxy users for the same proxied user.
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa40453900"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token comment" spellcheck="true">-- create proxy account</span>
<span class="token keyword">CREATE</span> <span class="token keyword">USER</span> <span class="token string">'[email protected]'</span>
<span class="token keyword">IDENTIFIED</span> <span class="token keyword">WITH</span> authentication_ldap_sasl
<span class="token keyword">BY</span> <span class="token string">'#krb_grp=proxied_krb_user'</span><span class="token punctuation">;</span>
<span class="token comment" spellcheck="true">-- create proxied account and grant its privileges;</span>
<span class="token comment" spellcheck="true">-- use mysql_no_login plugin to prevent direct login</span>
<span class="token keyword">CREATE</span> <span class="token keyword">USER</span> <span class="token string">'proxied_krb_user'</span>
<span class="token keyword">IDENTIFIED</span> <span class="token keyword">WITH</span> mysql_no_login<span class="token punctuation">;</span>
<span class="token keyword">GRANT</span> <span class="token keyword">ALL</span>
<span class="token keyword">ON</span> krb_user_db<span class="token punctuation">.</span><span class="token operator">*</span>
<span class="token keyword">TO</span> <span class="token string">'proxied_krb_user'</span><span class="token punctuation">;</span>
<span class="token comment" spellcheck="true">-- grant to proxy account the</span>
<span class="token comment" spellcheck="true">-- PROXY privilege for proxied account</span>
<span class="token keyword">GRANT</span> <span class="token keyword">PROXY</span>
<span class="token keyword">ON</span> <span class="token string">'proxied_krb_user'</span>
<span class="token keyword">TO</span> <span class="token string">'[email protected]'</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
Observe closely the quoting for the proxy account name in the
first
<a class="link" href="create-user.html" title="15.7.1.3 CREATE USER Statement">
<code class="literal">
CREATE USER
</code>
</a>
statement and
the
<a class="link" href="grant.html" title="15.7.1.6 GRANT Statement">
<code class="literal">
GRANT
PROXY
</code>
</a>
statement:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
For most MySQL accounts, the user and host are separate
parts of the account name, and thus are quoted separately
as
<code class="literal">
'
<em class="replaceable">
<code>
user_name
</code>
</em>
'@'
<em class="replaceable">
<code>
host_name
</code>
</em>
'
</code>
.
</p>
</li>
<li class="listitem">
<p>
For LDAP Kerberos authentication, the user part of the
account name includes the principal domain, so
<code class="literal">
'[email protected]'
</code>
is quoted as a
single value. Because no host part is given, the full
MySQL account name uses the default of
<code class="literal">
'%'
</code>
as the host part:
<code class="literal">
'[email protected]'@'%'
</code>
</p>
</li>
</ul>
</div>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Note
</div>
<p>
When creating an account that authenticates using the
<code class="literal">
authentication_ldap_sasl
</code>
SASL LDAP
authentication plugin with the GSSAPI/Kerberos
authentication method, the
<a class="link" href="create-user.html" title="15.7.1.3 CREATE USER Statement">
<code class="literal">
CREATE
USER
</code>
</a>
statement includes the realm as part of the
user name. This differs from creating accounts that use the
<code class="literal">
authentication_kerberos
</code>
Kerberos plugin.
For such accounts, the
<a class="link" href="create-user.html" title="15.7.1.3 CREATE USER Statement">
<code class="literal">
CREATE
USER
</code>
</a>
statement does not include the realm as part
of the user name. Instead, specify the realm as the
authentication string in the
<code class="literal">
BY
</code>
clause.
See
<a class="xref" href="kerberos-pluggable-authentication.html#kerberos-usage-mysql-account-setup" title="Create a MySQL Account That Uses Kerberos Authentication">
Create a MySQL Account That Uses Kerberos Authentication
</a>
.
</p>
</div>
<p>
The proxied account uses the
<code class="literal">
mysql_no_login
</code>
authentication plugin to prevent clients from using the
account to log in directly to the MySQL server. Instead, it is
expected that users who authenticate using LDAP use the
<code class="literal">
[email protected]
</code>
proxy account. (This
assumes that the
<code class="literal">
mysql_no_login
</code>
plugin is
installed. For instructions, see
<a class="xref" href="no-login-pluggable-authentication.html" title="8.4.1.9 No-Login Pluggable Authentication">
Section 8.4.1.9, “No-Login Pluggable Authentication”
</a>
.) For
alternative methods of protecting proxied accounts against
direct use, see
<a class="xref" href="proxy-users.html#preventing-proxied-account-direct-login" title="Preventing Direct Login to Proxied Accounts">
Preventing Direct Login to Proxied Accounts
</a>
.
</p>
<h6>
<a name="ldap-gssapi-mysql-client-usage">
</a>
Use the MySQL Account to Connect to the MySQL Server
</h6>
<p>
After a MySQL account that authenticates using GSSAPI/Kerberos
has been set up, clients can use it to connect to the MySQL
server. Kerberos authentication can take place either prior to
or at the time of MySQL client program invocation:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
Prior to invoking the MySQL client program, the client
user can obtain a TGT from the KDC independently of MySQL.
For example, the client user can use
<span class="command">
<strong>
kinit
</strong>
</span>
to authenticate to Kerberos by
providing a Kerberos principal name and the principal
password:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-terminal"><div class="docs-select-all right" id="sa66008720"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal"><span class="token prompt">$> </span><span class="token command">kinit</span> bredon@MYSQL<span class="token punctuation">.</span>LOCAL
Password for bredon@MYSQL<span class="token punctuation">.</span>LOCAL<span class="token punctuation">:</span> <span class="token punctuation"></span><em class="replaceable"><span class="token punctuation">(</span>enter password here<span class="token punctuation">)</span></em><span class="token punctuation"></span></code></pre>
</div>
<p>
The resulting TGT is cached and becomes available for use
by other Kerberos-aware applications, such as programs
that use the client-side SASL LDAP authentication plugin.
In this case, the MySQL client program authenticates to
the MySQL server using the TGT, so invoke the client
without specifying a user name or password:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-terminal"><div class="docs-select-all right" id="sa36805530"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal">mysql <span class="token constant">--default-auth</span><span class="token attr-value"><span class="token punctuation">=</span>authentication_ldap_sasl_client</span></code></pre>
</div>
<p>
As just described, when the TGT is cached, user-name and
password options are not needed in the client command. If
the command includes them anyway, they are handled as
follows:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
If the command includes a user name, authentication
fails if that name does not match the principal name
in the TGT.
</p>
</li>
<li class="listitem">
<p>
If the command includes a password, the client-side
plugin ignores it. Because authentication is based on
the TGT, it can succeed
<span class="emphasis">
<em>
even if the
user-provided password is incorrect
</em>
</span>
. For
this reason, the plugin produces a warning if a valid
TGT is found that causes a password to be ignored.
</p>
</li>
</ul>
</div>
</li>
<li class="listitem">
<p>
If the Kerberos cache contains no TGT, the client-side
SASL LDAP authentication plugin itself can obtain the TGT
from the KDC. Invoke the client with options for the name
and password of the Kerberos principal associated with the
MySQL account (enter the command on a single line, then
enter the principal password when prompted):
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-terminal"><div class="docs-select-all right" id="sa82533636"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal">mysql <span class="token constant">--default-auth</span><span class="token attr-value"><span class="token punctuation">=</span>authentication_ldap_sasl_client</span>
<span class="token constant">--user</span><span class="token attr-value"><span class="token punctuation">=</span>[email protected]</span>
<span class="token property">--password</span></code></pre>
</div>
</li>
<li class="listitem">
<p>
If the Kerberos cache contains no TGT and the client
command specifies no principal name as the user name,
authentication fails.
</p>
</li>
</ul>
</div>
<p>
If you are uncertain whether a TGT exists, you can use
<span class="command">
<strong>
klist
</strong>
</span>
to check.
</p>
<p>
Authentication occurs as follows:
</p>
<div class="orderedlist">
<ol class="orderedlist" type="1">
<li class="listitem">
<p>
The client uses the TGT to authenticate using Kerberos.
</p>
</li>
<li class="listitem">
<p>
The server finds the LDAP entry for the principal and uses
it to authenticate the connection for the
<code class="literal">
[email protected]
</code>
MySQL proxy account.
</p>
</li>
<li class="listitem">
<p>
The group mapping information in the proxy account
authentication string
(
<code class="literal">
'#krb_grp=proxied_krb_user'
</code>
) indicates
that the authenticated proxied user should be
<code class="literal">
proxied_krb_user
</code>
.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
[email protected]
</code>
is treated as a
proxy for
<code class="literal">
proxied_krb_user
</code>
, and the
following query returns output as shown:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa42706334"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">USER</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">,</span> <span class="token function">CURRENT_USER</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">,</span> <span class="token variable">@@proxy_user</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> USER() <span class="token punctuation">|</span> CURRENT_USER() <span class="token punctuation">|</span> @@proxy_user <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> [email protected]@localhost <span class="token punctuation">|</span> proxied_krb_user@% <span class="token punctuation">|</span> '[email protected]'@'%' <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span></code></pre>
</div>
<p>
The
<a class="link" href="information-functions.html#function_user">
<code class="literal">
USER()
</code>
</a>
value indicates
the user name used for the client command
(
<code class="literal">
[email protected]
</code>
) and the host from
which the client connected (
<code class="literal">
localhost
</code>
).
</p>
<p>
The
<a class="link" href="information-functions.html#function_current-user">
<code class="literal">
CURRENT_USER()
</code>
</a>
value is
the full name of the proxied user account, which consists
of the
<code class="literal">
proxied_krb_user
</code>
user part and
the
<code class="literal">
%
</code>
host part.
</p>
<p>
The
<a class="link" href="server-system-variables.html#sysvar_proxy_user">
<code class="literal">
@@proxy_user
</code>
</a>
value indicates the full name of the account used to make
the connection to the MySQL server, which consists of the
<code class="literal">
[email protected]
</code>
user part and the
<code class="literal">
%
</code>
host part.
</p>
<p>
This demonstrates that proxying occurs through the
<code class="literal">
[email protected]
</code>
proxy user account,
and that
<code class="literal">
[email protected]
</code>
assumes the
privileges granted to the
<code class="literal">
proxied_krb_user
</code>
proxied user account.
</p>
</li>
</ol>
</div>
<p>
A TGT once obtained is cached on the client side and can be
used until it expires without specifying the password again.
However the TGT is obtained, the client-side plugin uses it to
acquire service tickets and communicate with the server-side
plugin.
</p>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Note
</div>
<p>
When the client-side authentication plugin itself obtains
the TGT, the client user may not want the TGT to be reused.
As described in
<a class="xref" href="ldap-pluggable-authentication.html#ldap-gssapi-mysql-client-config-parameters" title="Client Configuration Parameters for LDAP Authentication">
Client Configuration Parameters for LDAP Authentication
</a>
,
the local
<code class="literal">
/etc/krb5.conf
</code>
file can be used
to cause the client-side plugin to destroy the TGT when done
with it.
</p>
</div>
<p>
The server-side plugin has no access to the TGT itself or the
Kerberos password used to obtain it.
</p>
<p>
The LDAP authentication plugins have no control over the
caching mechanism (storage in a local file, in memory, and so
forth), but Kerberos utilities such as
<span class="command">
<strong>
kswitch
</strong>
</span>
may be available for this purpose.
</p>
<h6>
<a name="ldap-gssapi-mysql-client-config-parameters">
</a>
Client Configuration Parameters for LDAP Authentication
</h6>
<p>
The
<code class="literal">
authentication_ldap_sasl_client
</code>
client-side SASL LDAP plugin reads the local
<code class="filename">
/etc/krb5.conf
</code>
file. If this file is
missing or inaccessible, an error occurs. Assuming that the
file is accessible, it can include an optional
<code class="literal">
[appdefaults]
</code>
section to provide
information used by the plugin. Place the information within
the
<code class="literal">
mysql
</code>
part of the section. For example:
</p>
<a class="indexterm" name="idm46045244691904">
</a>
<a class="indexterm" name="idm46045244690416">
</a>
<a class="indexterm" name="idm46045244688928">
</a>
<a class="indexterm" name="idm46045244687424">
</a>
<a class="indexterm" name="idm46045244685920">
</a>
<a class="indexterm" name="idm46045244684416">
</a>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-ini"><div class="docs-select-all right" id="sa78723544"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-ini"><span class="token selector">[appdefaults]</span>
<span class="token constant"> mysql</span> <span class="token attr-value"><span class="token punctuation">=</span> {</span>
<span class="token constant"> ldap_server_host</span> <span class="token attr-value"><span class="token punctuation">=</span> "ldap_host.example.com"</span>
<span class="token constant"> ldap_destroy_tgt</span> <span class="token attr-value"><span class="token punctuation">=</span> true</span>
}</code></pre>
</div>
<p>
The client-side plugin recognizes these parameters in the
<code class="literal">
mysql
</code>
section:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
The
<code class="literal">
ldap_server_host
</code>
value specifies
the LDAP server host and can be useful when that host
differs from the KDC server host specified in the
<code class="literal">
[realms]
</code>
section. By default, the
plugin uses the KDC server host as the LDAP server host.
</p>
</li>
<li class="listitem">
<p>
The
<code class="literal">
ldap_destroy_tgt
</code>
value indicates
whether the client-side plugin destroys the TGT after
obtaining and using it. By default,
<code class="literal">
ldap_destroy_tgt
</code>
is
<code class="literal">
false
</code>
, but can be set to
<code class="literal">
true
</code>
to avoid TGT reuse. (This setting
applies only to TGTs created by the client-side plugin,
not TGTs created by other plugins or externally to MySQL.)
</p>
</li>
</ul>
</div>
</div>
<div class="simplesect">
<div class="titlepage">
<div>
<div class="simple">
<h5 class="title">
<a name="ldap-pluggable-authentication-ldap-referral">
</a>
LDAP Search Referral
</h5>
</div>
</div>
</div>
<p>
An LDAP server can be configured to delegate LDAP searches to
another LDAP server, a functionality known as LDAP referral.
Suppose that the server
<code class="literal">
a.example.com
</code>
holds
a
<code class="literal">
"dc=example,dc=com"
</code>
root DN and wishes to
delegate searches to another server
<code class="literal">
b.example.com
</code>
. To enable this,
<code class="literal">
a.example.com
</code>
would be configured with a
named referral object having these attributes:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-simple"><div class="docs-select-all right" id="sa47149693"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-simple">dn<span class="token operator">:</span> dc<span class="token operator">=</span>subtree<span class="token punctuation">,</span>dc<span class="token operator">=</span>example<span class="token punctuation">,</span>dc<span class="token operator">=</span>com
objectClass<span class="token operator">:</span> referral
objectClass<span class="token operator">:</span> extensibleObject
dc<span class="token operator">:</span> subtree
ref<span class="token operator">:</span> ldap<span class="token operator">:</span><span class="token operator">/</span><span class="token operator">/</span>b<span class="token punctuation">.</span>example<span class="token punctuation">.</span>com<span class="token operator">/</span>dc<span class="token operator">=</span>subtree<span class="token punctuation">,</span>dc<span class="token operator">=</span>example<span class="token punctuation">,</span>dc<span class="token operator">=</span>com</code></pre>
</div>
<p>
An issue with enabling LDAP referral is that searches can fail
with LDAP operation errors when the search base DN is the root
DN, and referral objects are not set. A MySQL DBA might wish
to avoid such referral errors for the LDAP authentication
plugins, even though LDAP referral might be set globally in
the
<code class="filename">
ldap.conf
</code>
configuration file. To
configure on a plugin-specific basis whether the LDAP server
should use LDAP referral when communicating with each plugin,
set the
<a class="link" href="pluggable-authentication-system-variables.html#sysvar_authentication_ldap_simple_referral">
<code class="literal">
authentication_ldap_simple_referral
</code>
</a>
and
<a class="link" href="pluggable-authentication-system-variables.html#sysvar_authentication_ldap_sasl_referral">
<code class="literal">
authentication_ldap_sasl_referral
</code>
</a>
system variables. Setting either variable to
<code class="literal">
ON
</code>
or
<code class="literal">
OFF
</code>
causes the
corresponding LDAP authentication plugin to tell the LDAP
server whether to use referral during MySQL authentication.
Each variable has a plugin-specific effect and does not affect
other applications that communicate with the LDAP server. Both
variables are
<code class="literal">
OFF
</code>
by default.
</p>
</div>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/replication-options-gtids.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="replication-options-gtids">
</a>
19.1.6.5 Global Transaction ID System Variables
</h4>
</div>
</div>
</div>
<p>
The MySQL Server system variables described in this section are
used to monitor and control Global Transaction Identifiers
(GTIDs). For additional information, see
<a class="xref" href="replication-gtids.html" title="19.1.3 Replication with Global Transaction Identifiers">
Section 19.1.3, “Replication with Global Transaction Identifiers”
</a>
.
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<a name="sysvar_binlog_gtid_simple_recovery">
</a>
<a class="link" href="replication-options-gtids.html#sysvar_binlog_gtid_simple_recovery">
<code class="literal">
binlog_gtid_simple_recovery
</code>
</a>
</p>
<a class="indexterm" name="idm46045139222720">
</a>
<a class="indexterm" name="idm46045139221632">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for binlog_gtid_simple_recovery">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--binlog-gtid-simple-recovery[={OFF|ON}]
</code>
</td>
</tr>
<tr>
<th>
System Variable
</th>
<td>
<code class="literal">
<a class="link" href="replication-options-gtids.html#sysvar_binlog_gtid_simple_recovery">
binlog_gtid_simple_recovery
</a>
</code>
</td>
</tr>
<tr>
<th>
Scope
</th>
<td>
Global
</td>
</tr>
<tr>
<th>
Dynamic
</th>
<td>
No
</td>
</tr>
<tr>
<th>
<a class="link" href="optimizer-hints.html#optimizer-hints-set-var" title="Variable-Setting Hint Syntax">
<code class="literal">
SET_VAR
</code>
</a>
Hint Applies
</th>
<td>
No
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Boolean
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
ON
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
This variable controls how binary log files are iterated
during the search for GTIDs when MySQL starts or restarts.
</p>
<p>
When
<a class="link" href="replication-options-gtids.html#sysvar_binlog_gtid_simple_recovery">
<code class="literal">
binlog_gtid_simple_recovery=TRUE
</code>
</a>
(the default), the values of
<a class="link" href="replication-options-gtids.html#sysvar_gtid_executed">
<code class="literal">
gtid_executed
</code>
</a>
and
<a class="link" href="replication-options-gtids.html#sysvar_gtid_purged">
<code class="literal">
gtid_purged
</code>
</a>
are computed at
startup based on the values of
<code class="literal">
Previous_gtids_log_event
</code>
in the most recent
and oldest binary log files. For a description of the
computation, see
<a class="xref" href="replication-gtids-lifecycle.html#replication-gtids-gtid-purged" title="The gtid_purged System Variable">
The
<code class="literal">
gtid_purged
</code>
System Variable
</a>
. This setting
accesses only two binary log files during server restart. If
all binary logs on the server were generated using MySQL 5.7.8
or later,
<a class="link" href="replication-options-gtids.html#sysvar_binlog_gtid_simple_recovery">
<code class="literal">
binlog_gtid_simple_recovery=TRUE
</code>
</a>
can always safely be used.
</p>
<p>
If any binary logs from MySQL 5.7.7 or older are present on
the server (for example, following an upgrade of an older
server to MySQL 8.4), with
<a class="link" href="replication-options-gtids.html#sysvar_binlog_gtid_simple_recovery">
<code class="literal">
binlog_gtid_simple_recovery=TRUE
</code>
</a>
,
<a class="link" href="replication-options-gtids.html#sysvar_gtid_executed">
<code class="literal">
gtid_executed
</code>
</a>
and
<a class="link" href="replication-options-gtids.html#sysvar_gtid_purged">
<code class="literal">
gtid_purged
</code>
</a>
might be
initialized incorrectly in the following two situations:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
The newest binary log was generated by MySQL 5.7.5 or
earlier, and
<a class="link" href="replication-options-gtids.html#sysvar_gtid_mode">
<code class="literal">
gtid_mode
</code>
</a>
was
<code class="literal">
ON
</code>
for some binary logs but
<code class="literal">
OFF
</code>
for the newest binary log.
</p>
</li>
<li class="listitem">
<p>
A
<code class="literal">
SET @@GLOBAL.gtid_purged
</code>
statement
was issued on MySQL 5.7.7 or earlier, and the binary log
that was active at the time of the
<code class="literal">
SET
@@GLOBAL.gtid_purged
</code>
statement has not yet been
purged.
</p>
</li>
</ul>
</div>
<p>
If an incorrect GTID set is computed in either situation, it
remains incorrect even if the server is later restarted with
<a class="link" href="replication-options-gtids.html#sysvar_binlog_gtid_simple_recovery">
<code class="literal">
binlog_gtid_simple_recovery=FALSE
</code>
</a>
.
If either of these situations apply or might apply on the
server, set
<a class="link" href="replication-options-gtids.html#sysvar_binlog_gtid_simple_recovery">
<code class="literal">
binlog_gtid_simple_recovery=FALSE
</code>
</a>
before starting or restarting the server.
</p>
<p>
When
<a class="link" href="replication-options-gtids.html#sysvar_binlog_gtid_simple_recovery">
<code class="literal">
binlog_gtid_simple_recovery=FALSE
</code>
</a>
is set, the method of computing
<a class="link" href="replication-options-gtids.html#sysvar_gtid_executed">
<code class="literal">
gtid_executed
</code>
</a>
and
<a class="link" href="replication-options-gtids.html#sysvar_gtid_purged">
<code class="literal">
gtid_purged
</code>
</a>
as described in
<a class="xref" href="replication-gtids-lifecycle.html#replication-gtids-gtid-purged" title="The gtid_purged System Variable">
The
<code class="literal">
gtid_purged
</code>
System Variable
</a>
is changed to
iterate the binary log files as follows:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
Instead of using the value of
<code class="literal">
Previous_gtids_log_event
</code>
and GTID log
events from the newest binary log file, the computation
for
<a class="link" href="replication-options-gtids.html#sysvar_gtid_executed">
<code class="literal">
gtid_executed
</code>
</a>
iterates from the newest binary log file, and uses the
value of
<code class="literal">
Previous_gtids_log_event
</code>
and
any GTID log events from the first binary log file where
it finds a
<code class="literal">
Previous_gtids_log_event
</code>
value. If the server's most recent binary log files do not
have GTID log events, for example if
<a class="link" href="replication-options-gtids.html#sysvar_gtid_mode">
<code class="literal">
gtid_mode=ON
</code>
</a>
was used but
the server was later changed to
<a class="link" href="replication-options-gtids.html#sysvar_gtid_mode">
<code class="literal">
gtid_mode=OFF
</code>
</a>
, this
process can take a long time.
</p>
</li>
<li class="listitem">
<p>
Instead of using the value of
<code class="literal">
Previous_gtids_log_event
</code>
from the
oldest binary log file, the computation for
<a class="link" href="replication-options-gtids.html#sysvar_gtid_purged">
<code class="literal">
gtid_purged
</code>
</a>
iterates from
the oldest binary log file, and uses the value of
<code class="literal">
Previous_gtids_log_event
</code>
from the first
binary log file where it finds either a nonempty
<code class="literal">
Previous_gtids_log_event
</code>
value, or at
least one GTID log event (indicating that the use of GTIDs
starts at that point). If the server's older binary log
files do not have GTID log events, for example if
<a class="link" href="replication-options-gtids.html#sysvar_gtid_mode">
<code class="literal">
gtid_mode=ON
</code>
</a>
was only set
recently on the server, this process can take a long time.
</p>
</li>
</ul>
</div>
</li>
<li class="listitem">
<p>
<a name="sysvar_enforce_gtid_consistency">
</a>
<a class="link" href="replication-options-gtids.html#sysvar_enforce_gtid_consistency">
<code class="literal">
enforce_gtid_consistency
</code>
</a>
</p>
<a class="indexterm" name="idm46045139156944">
</a>
<a class="indexterm" name="idm46045139155840">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for enforce_gtid_consistency">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--enforce-gtid-consistency[=value]
</code>
</td>
</tr>
<tr>
<th>
System Variable
</th>
<td>
<code class="literal">
<a class="link" href="replication-options-gtids.html#sysvar_enforce_gtid_consistency">
enforce_gtid_consistency
</a>
</code>
</td>
</tr>
<tr>
<th>
Scope
</th>
<td>
Global
</td>
</tr>
<tr>
<th>
Dynamic
</th>
<td>
Yes
</td>
</tr>
<tr>
<th>
<a class="link" href="optimizer-hints.html#optimizer-hints-set-var" title="Variable-Setting Hint Syntax">
<code class="literal">
SET_VAR
</code>
</a>
Hint Applies
</th>
<td>
No
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Enumeration
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
OFF
</code>
</td>
</tr>
<tr>
<th>
Valid Values
</th>
<td>
<p class="valid-value">
<code class="literal">
OFF
</code>
</p>
<p class="valid-value">
<code class="literal">
ON
</code>
</p>
<p class="valid-value">
<code class="literal">
WARN
</code>
</p>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Depending on the value of this variable, the server enforces
GTID consistency by allowing execution of only statements that
can be safely logged using a GTID. You
<span class="emphasis">
<em>
must
</em>
</span>
set this variable to
<code class="literal">
ON
</code>
before enabling GTID based replication.
</p>
<p>
The values that
<a class="link" href="replication-options-gtids.html#sysvar_enforce_gtid_consistency">
<code class="literal">
enforce_gtid_consistency
</code>
</a>
can
be configured to are:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
<code class="literal">
OFF
</code>
: all transactions are allowed to
violate GTID consistency.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
ON
</code>
: no transaction is allowed to
violate GTID consistency.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
WARN
</code>
: all transactions are allowed to
violate GTID consistency, but a warning is generated in
this case.
</p>
</li>
</ul>
</div>
<p>
<a class="link" href="replication-options-gtids.html#sysvar_enforce_gtid_consistency">
<code class="option">
--enforce-gtid-consistency
</code>
</a>
only
takes effect if binary logging takes place for a statement. If
binary logging is disabled on the server, or if statements are
not written to the binary log because they are removed by a
filter, GTID consistency is not checked or enforced for the
statements that are not logged.
</p>
<p>
Only statements that can be logged using GTID safe statements
can be logged when
<a class="link" href="replication-options-gtids.html#sysvar_enforce_gtid_consistency">
<code class="literal">
enforce_gtid_consistency
</code>
</a>
is
set to
<code class="literal">
ON
</code>
, so the operations listed here
cannot be used with this option:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
<a class="link" href="create-table.html" title="15.1.20 CREATE TABLE Statement">
<code class="literal">
CREATE
TEMPORARY TABLE
</code>
</a>
or
<a class="link" href="drop-table.html" title="15.1.32 DROP TABLE Statement">
<code class="literal">
DROP TEMPORARY
TABLE
</code>
</a>
statements inside transactions.
</p>
</li>
<li class="listitem">
<p>
Transactions or statements that update both transactional
and nontransactional tables. There is an exception that
nontransactional DML is allowed in the same transaction or
in the same statement as transactional DML, if all
<span class="emphasis">
<em>
nontransactional
</em>
</span>
tables are
temporary.
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="create-table-select.html" title="15.1.20.4 CREATE TABLE ... SELECT Statement">
<code class="literal">
CREATE
TABLE ... SELECT
</code>
</a>
statements are supported for
storage engines that support atomic DDL.
</p>
</li>
</ul>
</div>
<p>
For more information, see
<a class="xref" href="replication-gtids-restrictions.html" title="19.1.3.7 Restrictions on Replication with GTIDs">
Section 19.1.3.7, “Restrictions on Replication with GTIDs”
</a>
.
</p>
<p>
Prior to MySQL 5.7 and in early releases in that release
series, the boolean
<a class="link" href="replication-options-gtids.html#sysvar_enforce_gtid_consistency">
<code class="literal">
enforce_gtid_consistency
</code>
</a>
defaulted to
<code class="literal">
OFF
</code>
. To maintain compatibility
with these earlier releases, the enumeration defaults to
<code class="literal">
OFF
</code>
, and setting
<a class="link" href="replication-options-gtids.html#sysvar_enforce_gtid_consistency">
<code class="option">
--enforce-gtid-consistency
</code>
</a>
without a value is interpreted as setting the value to
<code class="literal">
ON
</code>
. The variable also has multiple textual
aliases for the values:
<code class="literal">
0=OFF=FALSE
</code>
,
<code class="literal">
1=ON=TRUE
</code>
,
<code class="literal">
2=WARN
</code>
. This
differs from other enumeration types but maintains
compatibility with the boolean type used in previous releases.
These changes impact on what is returned by the variable.
Using
<code class="literal">
SELECT @@ENFORCE_GTID_CONSISTENCY
</code>
,
<code class="literal">
SHOW VARIABLES LIKE
'ENFORCE_GTID_CONSISTENCY'
</code>
, and
<code class="literal">
SELECT *
FROM INFORMATION_SCHEMA.VARIABLES WHERE 'VARIABLE_NAME' =
'ENFORCE_GTID_CONSISTENCY'
</code>
, all return the textual
form, not the numeric form. This is an incompatible change,
since
<code class="literal">
@@ENFORCE_GTID_CONSISTENCY
</code>
returns
the numeric form for booleans but returns the textual form for
<code class="literal">
SHOW
</code>
and the Information Schema.
</p>
</li>
<li class="listitem">
<p>
<a name="sysvar_gtid_executed">
</a>
<a class="link" href="replication-options-gtids.html#sysvar_gtid_executed">
<code class="literal">
gtid_executed
</code>
</a>
</p>
<a class="indexterm" name="idm46045139094400">
</a>
<a class="indexterm" name="idm46045139093312">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for gtid_executed">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
System Variable
</th>
<td>
<code class="literal">
<a class="link" href="replication-options-gtids.html#sysvar_gtid_executed">
gtid_executed
</a>
</code>
</td>
</tr>
<tr>
<th>
Scope
</th>
<td>
Global
</td>
</tr>
<tr>
<th>
Dynamic
</th>
<td>
No
</td>
</tr>
<tr>
<th>
<a class="link" href="optimizer-hints.html#optimizer-hints-set-var" title="Variable-Setting Hint Syntax">
<code class="literal">
SET_VAR
</code>
</a>
Hint Applies
</th>
<td>
No
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
String
</td>
</tr>
<tr>
<th>
Unit
</th>
<td>
set of GTIDs
</td>
</tr>
</tbody>
</table>
</div>
<p>
When used with global scope, this variable contains a
representation of the set of all transactions executed on the
server and GTIDs that have been set by a
<a class="link" href="set-variable.html" title="15.7.6.1 SET Syntax for Variable Assignment">
<code class="literal">
SET
</code>
</a>
<a class="link" href="replication-options-gtids.html#sysvar_gtid_purged">
<code class="literal">
gtid_purged
</code>
</a>
statement. This
is the same as the value of the
<code class="literal">
Executed_Gtid_Set
</code>
column in the output of
<a class="link" href="show-binary-log-status.html" title="15.7.7.1 SHOW BINARY LOG STATUS Statement">
<code class="literal">
SHOW BINARY LOG STATUS
</code>
</a>
and
<a class="link" href="show-replica-status.html" title="15.7.7.35 SHOW REPLICA STATUS Statement">
<code class="literal">
SHOW REPLICA STATUS
</code>
</a>
. The value
of this variable is a GTID set, see
<a class="xref" href="replication-gtids-concepts.html#replication-gtids-concepts-gtid-sets" title="GTID Sets">
GTID Sets
</a>
for
more information.
</p>
<p>
When the server starts,
<code class="literal">
@@GLOBAL.gtid_executed
</code>
is initialized. See
<a class="link" href="replication-options-gtids.html#sysvar_binlog_gtid_simple_recovery">
<code class="literal">
binlog_gtid_simple_recovery
</code>
</a>
for more information on how binary logs are iterated to
populate
<a class="link" href="replication-options-gtids.html#sysvar_gtid_executed">
<code class="literal">
gtid_executed
</code>
</a>
. GTIDs
are then added to the set as transactions are executed, or if
any
<a class="link" href="set-variable.html" title="15.7.6.1 SET Syntax for Variable Assignment">
<code class="literal">
SET
</code>
</a>
<a class="link" href="replication-options-gtids.html#sysvar_gtid_purged">
<code class="literal">
gtid_purged
</code>
</a>
statement is
executed.
</p>
<p>
The set of transactions that can be found in the binary logs
at any given time is equal to
<a class="link" href="gtid-functions.html#function_gtid-subtract">
<code class="literal">
GTID_SUBTRACT(@@GLOBAL.gtid_executed,
@@GLOBAL.gtid_purged)
</code>
</a>
; that is, to all transactions
in the binary log that have not yet been purged.
</p>
<p>
Issuing
<a class="link" href="reset-binary-logs-and-gtids.html" title="15.4.1.2 RESET BINARY LOGS AND GTIDS Statement">
<code class="literal">
RESET BINARY LOGS AND
GTIDS
</code>
</a>
causes this variable to be reset to an empty
string. GTIDs are not otherwise removed from this set other
than when the set is cleared due to
<code class="literal">
RESET BINARY LOGS
AND GTIDS
</code>
.
</p>
</li>
<li class="listitem">
<p>
<a name="sysvar_gtid_executed_compression_period">
</a>
<a class="link" href="replication-options-gtids.html#sysvar_gtid_executed_compression_period">
<code class="literal">
gtid_executed_compression_period
</code>
</a>
</p>
<a class="indexterm" name="idm46045139054352">
</a>
<a class="indexterm" name="idm46045139053264">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for gtid_executed_compression_period">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--gtid-executed-compression-period=#
</code>
</td>
</tr>
<tr>
<th>
System Variable
</th>
<td>
<code class="literal">
<a class="link" href="replication-options-gtids.html#sysvar_gtid_executed_compression_period">
gtid_executed_compression_period
</a>
</code>
</td>
</tr>
<tr>
<th>
Scope
</th>
<td>
Global
</td>
</tr>
<tr>
<th>
Dynamic
</th>
<td>
Yes
</td>
</tr>
<tr>
<th>
<a class="link" href="optimizer-hints.html#optimizer-hints-set-var" title="Variable-Setting Hint Syntax">
<code class="literal">
SET_VAR
</code>
</a>
Hint Applies
</th>
<td>
No
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Integer
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
0
</code>
</td>
</tr>
<tr>
<th>
Minimum Value
</th>
<td>
<code class="literal">
0
</code>
</td>
</tr>
<tr>
<th>
Maximum Value
</th>
<td>
<code class="literal">
4294967295
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Compress the
<code class="literal">
mysql.gtid_executed
</code>
table each
time this many transactions have been processed. When binary
logging is enabled on the server, this compression method is
not used, and instead the
<code class="literal">
mysql.gtid_executed
</code>
table is compressed on
each binary log rotation. When binary logging is disabled on
the server, the compression thread sleeps until the specified
number of transactions have been executed, then wakes up to
perform compression of the
<code class="literal">
mysql.gtid_executed
</code>
table. Setting the
value of this system variable to 0 means that the thread never
wakes up, so this explicit compression method is not used.
Instead, compression occurs implicitly as required.
</p>
<p>
<code class="literal">
InnoDB
</code>
transactions are written to the
<code class="literal">
mysql.gtid_executed
</code>
table by a separate
process to non-
<code class="literal">
InnoDB
</code>
transactions. If the
server has a mix of
<code class="literal">
InnoDB
</code>
transactions and
non-
<code class="literal">
InnoDB
</code>
transactions, the compression
controlled by this system variable interferes with the work of
this process and can slow it significantly. For this reason,
from that release it is recommended that you set
<a class="link" href="replication-options-gtids.html#sysvar_gtid_executed_compression_period">
<code class="literal">
gtid_executed_compression_period
</code>
</a>
to 0.
</p>
<p>
All transactions (regardless of storage engine) are written to
the
<code class="literal">
mysql.gtid_executed
</code>
table by the same
process, and the
<a class="link" href="replication-options-gtids.html#sysvar_gtid_executed_compression_period">
<code class="literal">
gtid_executed_compression_period
</code>
</a>
default value is 0.
</p>
<p>
See
<a class="xref" href="replication-gtids-concepts.html#replication-gtids-gtid-executed-table-compression" title="mysql.gtid_executed Table Compression">
mysql.gtid_executed Table Compression
</a>
for more information.
</p>
</li>
<li class="listitem">
<p>
<a name="sysvar_gtid_mode">
</a>
<a class="link" href="replication-options-gtids.html#sysvar_gtid_mode">
<code class="literal">
gtid_mode
</code>
</a>
</p>
<a class="indexterm" name="idm46045139011728">
</a>
<a class="indexterm" name="idm46045139010640">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for gtid_mode">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--gtid-mode=MODE
</code>
</td>
</tr>
<tr>
<th>
System Variable
</th>
<td>
<code class="literal">
<a class="link" href="replication-options-gtids.html#sysvar_gtid_mode">
gtid_mode
</a>
</code>
</td>
</tr>
<tr>
<th>
Scope
</th>
<td>
Global
</td>
</tr>
<tr>
<th>
Dynamic
</th>
<td>
Yes
</td>
</tr>
<tr>
<th>
<a class="link" href="optimizer-hints.html#optimizer-hints-set-var" title="Variable-Setting Hint Syntax">
<code class="literal">
SET_VAR
</code>
</a>
Hint Applies
</th>
<td>
No
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Enumeration
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
OFF
</code>
</td>
</tr>
<tr>
<th>
Valid Values
</th>
<td>
<p class="valid-value">
<code class="literal">
OFF
</code>
</p>
<p class="valid-value">
<code class="literal">
OFF_PERMISSIVE
</code>
</p>
<p class="valid-value">
<code class="literal">
ON_PERMISSIVE
</code>
</p>
<p class="valid-value">
<code class="literal">
ON
</code>
</p>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Controls whether GTID based logging is enabled and what type
of transactions the logs can contain. You must have privileges
sufficient to set global system variables. See
<a class="xref" href="system-variable-privileges.html" title="7.1.9.1 System Variable Privileges">
Section 7.1.9.1, “System Variable Privileges”
</a>
.
<a class="link" href="replication-options-gtids.html#sysvar_enforce_gtid_consistency">
<code class="literal">
enforce_gtid_consistency
</code>
</a>
must
be set to
<code class="literal">
ON
</code>
before you can set
<a class="link" href="replication-options-gtids.html#sysvar_gtid_mode">
<code class="literal">
gtid_mode=ON
</code>
</a>
. Before
modifying this variable, see
<a class="xref" href="replication-mode-change-online.html" title="19.1.4 Changing GTID Mode on Online Servers">
Section 19.1.4, “Changing GTID Mode on Online Servers”
</a>
.
</p>
<p>
Logged transactions can be either anonymous or use GTIDs.
Anonymous transactions rely on binary log file and position to
identify specific transactions. GTID transactions have a
unique identifier that is used to refer to transactions. The
different modes are:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
<code class="literal">
OFF
</code>
: Both new and replicated
transactions must be anonymous.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
OFF_PERMISSIVE
</code>
: New transactions are
anonymous. Replicated transactions can be either anonymous
or GTID transactions.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
ON_PERMISSIVE
</code>
: New transactions are
GTID transactions. Replicated transactions can be either
anonymous or GTID transactions.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
ON
</code>
: Both new and replicated
transactions must be GTID transactions.
</p>
</li>
</ul>
</div>
<p>
Changes from one value to another can only be one step at a
time. For example, if
<a class="link" href="replication-options-gtids.html#sysvar_gtid_mode">
<code class="literal">
gtid_mode
</code>
</a>
is currently set to
<code class="literal">
OFF_PERMISSIVE
</code>
, it is possible to change to
<code class="literal">
OFF
</code>
or
<code class="literal">
ON_PERMISSIVE
</code>
but
not to
<code class="literal">
ON
</code>
.
</p>
<p>
The values of
<a class="link" href="replication-options-gtids.html#sysvar_gtid_purged">
<code class="literal">
gtid_purged
</code>
</a>
and
<a class="link" href="replication-options-gtids.html#sysvar_gtid_executed">
<code class="literal">
gtid_executed
</code>
</a>
are persistent
regardless of the value of
<a class="link" href="replication-options-gtids.html#sysvar_gtid_mode">
<code class="literal">
gtid_mode
</code>
</a>
. Therefore even
after changing the value of
<a class="link" href="replication-options-gtids.html#sysvar_gtid_mode">
<code class="literal">
gtid_mode
</code>
</a>
, these variables
contain the correct values.
</p>
</li>
<li class="listitem">
<p>
<a name="sysvar_gtid_next">
</a>
<a class="link" href="replication-options-gtids.html#sysvar_gtid_next">
<code class="literal">
gtid_next
</code>
</a>
</p>
<a class="indexterm" name="idm46045138958240">
</a>
<a class="indexterm" name="idm46045138957152">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for gtid_next">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
System Variable
</th>
<td>
<code class="literal">
<a class="link" href="replication-options-gtids.html#sysvar_gtid_next">
gtid_next
</a>
</code>
</td>
</tr>
<tr>
<th>
Scope
</th>
<td>
Session
</td>
</tr>
<tr>
<th>
Dynamic
</th>
<td>
Yes
</td>
</tr>
<tr>
<th>
<a class="link" href="optimizer-hints.html#optimizer-hints-set-var" title="Variable-Setting Hint Syntax">
<code class="literal">
SET_VAR
</code>
</a>
Hint Applies
</th>
<td>
No
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Enumeration
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
AUTOMATIC
</code>
</td>
</tr>
<tr>
<th>
Valid Values
</th>
<td>
<p class="valid-value">
<code class="literal">
AUTOMATIC
</code>
</p>
<p class="valid-value">
<code class="literal">
AUTOMATIC:<TAG>
</code>
</p>
<p class="valid-value">
<code class="literal">
ANONYMOUS
</code>
</p>
<p class="valid-value">
<code class="literal">
<UUID>:<NUMBER>
</code>
</p>
<p class="valid-value">
<code class="literal">
<UUID>:<TAG>:<NUMBER>
</code>
</p>
</td>
</tr>
</tbody>
</table>
</div>
<p>
This variable is used to specify whether and how to otain the
next GTID (see
<a class="xref" href="replication-gtids.html" title="19.1.3 Replication with Global Transaction Identifiers">
Section 19.1.3, “Replication with Global Transaction Identifiers”
</a>
).
</p>
<p>
Setting the session value of this system variable is a
restricted operation. The session user must have either the
<a class="link" href="privileges-provided.html#priv_replication-applier">
<code class="literal">
REPLICATION_APPLIER
</code>
</a>
privilege
(see
<a class="xref" href="replication-privilege-checks.html" title="19.3.3 Replication Privilege Checks">
Section 19.3.3, “Replication Privilege Checks”
</a>
), or
privileges sufficient to set restricted session variables (see
<a class="xref" href="system-variable-privileges.html" title="7.1.9.1 System Variable Privileges">
Section 7.1.9.1, “System Variable Privileges”
</a>
).
</p>
<p>
<code class="literal">
gtid_next
</code>
can take any of the following
values:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
<code class="literal">
AUTOMATIC
</code>
: Use the next
automatically-generated global transaction ID.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
AUTOMATIC:
<em class="replaceable">
<code>
TAG
</code>
</em>
</code>
:
Use the next automatically-generated global transaction
ID, with the addition of a user-specified tag, in
UUID:
<em class="replaceable">
<code>
TAG
</code>
</em>
:NUMBER format.
</p>
<p>
The tag must match the regular expression
<code class="literal">
[a-z_][a-z0-9_]{0,7}
</code>
; in other words,
it must conform to the following rules:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: square; ">
<li class="listitem">
<p>
The tag must consist of 1-8 characters (inclusive).
</p>
</li>
<li class="listitem">
<p>
The first character can be any letter
<code class="literal">
a
</code>
through
<code class="literal">
z
</code>
, or
an underscore (
<code class="literal">
_
</code>
).
</p>
</li>
<li class="listitem">
<p>
Each of the remaining characters can be any of the
letters
<code class="literal">
a
</code>
through
<code class="literal">
z
</code>
, the digits
<code class="literal">
0
</code>
through
<code class="literal">
9
</code>
, or an underscore
(
<code class="literal">
_
</code>
).
</p>
</li>
</ul>
</div>
<p>
Setting
<code class="literal">
gtid_next
</code>
on the replication
source to
<code class="literal">
AUTOMATIC:
<em class="replaceable">
<code>
TAG
</code>
</em>
</code>
or
<code class="literal">
<em class="replaceable">
<code>
UUID
</code>
</em>
:
<em class="replaceable">
<code>
TAG
</code>
</em>
:
<em class="replaceable">
<code>
NUMBER
</code>
</em>
</code>
requires the
<a class="link" href="privileges-provided.html#priv_transaction-gtid-tag">
<code class="literal">
TRANSACTION_GTID_TAG
</code>
</a>
privilege plus at least one of the privileges
<a class="link" href="privileges-provided.html#priv_system-variables-admin">
<code class="literal">
SYSTEM_VARIABLES_ADMIN
</code>
</a>
,
<a class="link" href="privileges-provided.html#priv_session-variables-admin">
<code class="literal">
SESSION_VARIABLES_ADMIN
</code>
</a>
, or
<a class="link" href="privileges-provided.html#priv_replication-applier">
<code class="literal">
REPLICATION_APPLIER
</code>
</a>
. For
the
<code class="literal">
REPLICATION_CHECKS_APPLIER
</code>
this
privilege is also required to set
<code class="literal">
gtid_next
</code>
to either of these values, in
addition to the
<code class="literal">
REPLICATION_APPLIER
</code>
privilege; these privileges are checked when starting the
replication applier thread.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
ANONYMOUS
</code>
: Transactions do not have
global identifiers, and are identified by file and
position only.
</p>
</li>
<li class="listitem">
<p>
A global transaction ID in either of the formats
<em class="replaceable">
<code>
UUID
</code>
</em>
:
<em class="replaceable">
<code>
NUMBER
</code>
</em>
or
<em class="replaceable">
<code>
UUID
</code>
</em>
:
<em class="replaceable">
<code>
TAG
</code>
</em>
:
<em class="replaceable">
<code>
NUMBER
</code>
</em>
.
</p>
</li>
</ul>
</div>
<p>
Exactly which of the options just listed are valid depends on
the setting of
<a class="link" href="replication-options-gtids.html#sysvar_gtid_mode">
<code class="literal">
gtid_mode
</code>
</a>
; see
<a class="xref" href="replication-mode-change-online-concepts.html" title="19.1.4.1 Replication Mode Concepts">
Section 19.1.4.1, “Replication Mode Concepts”
</a>
for
more information. Setting this variable has no effect if
<a class="link" href="replication-options-gtids.html#sysvar_gtid_mode">
<code class="literal">
gtid_mode
</code>
</a>
is
<code class="literal">
OFF
</code>
.
</p>
<p>
After this variable has been set to
<code class="literal">
<em class="replaceable">
<code>
UUID
</code>
</em>
:
<em class="replaceable">
<code>
NUMBER
</code>
</em>
</code>
or
<code class="literal">
<em class="replaceable">
<code>
UUID
</code>
</em>
:
<em class="replaceable">
<code>
TAG
</code>
</em>
:
<em class="replaceable">
<code>
NUMBER
</code>
</em>
</code>
,
and a transaction has been committed or rolled back, an
explicit
<code class="literal">
SET gtid_next
</code>
statement must again
be issued before any other statement.
</p>
<p>
<a class="link" href="drop-table.html" title="15.1.32 DROP TABLE Statement">
<code class="literal">
DROP TABLE
</code>
</a>
or
<a class="link" href="drop-table.html" title="15.1.32 DROP TABLE Statement">
<code class="literal">
DROP TEMPORARY
TABLE
</code>
</a>
fails with an explicit error when used on a
combination of nontemporary tables with temporary tables, or
of temporary tables using transactional storage engines with
temporary tables using nontransactional storage engines.
</p>
<p>
For more information, see
<a class="xref" href="replication-gtids-lifecycle.html#replication-gtids-gtid-next" title="The gtid_next System Variable">
The gtid_next System Variable
</a>
, as well as
<a class="xref" href="replication-mode-change-online.html" title="19.1.4 Changing GTID Mode on Online Servers">
Section 19.1.4, “Changing GTID Mode on Online Servers”
</a>
.
</p>
</li>
<li class="listitem">
<p>
<a name="sysvar_gtid_owned">
</a>
<a class="link" href="replication-options-gtids.html#sysvar_gtid_owned">
<code class="literal">
gtid_owned
</code>
</a>
</p>
<a class="indexterm" name="idm46045138879504">
</a>
<a class="indexterm" name="idm46045138878416">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for gtid_owned">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
System Variable
</th>
<td>
<code class="literal">
<a class="link" href="replication-options-gtids.html#sysvar_gtid_owned">
gtid_owned
</a>
</code>
</td>
</tr>
<tr>
<th>
Scope
</th>
<td>
Global, Session
</td>
</tr>
<tr>
<th>
Dynamic
</th>
<td>
No
</td>
</tr>
<tr>
<th>
<a class="link" href="optimizer-hints.html#optimizer-hints-set-var" title="Variable-Setting Hint Syntax">
<code class="literal">
SET_VAR
</code>
</a>
Hint Applies
</th>
<td>
No
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
String
</td>
</tr>
<tr>
<th>
Unit
</th>
<td>
set of GTIDs
</td>
</tr>
</tbody>
</table>
</div>
<p>
This read-only variable is primarily for internal use. Its
contents depend on its scope.
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
When used with global scope,
<a class="link" href="replication-options-gtids.html#sysvar_gtid_owned">
<code class="literal">
gtid_owned
</code>
</a>
holds a list
of all the GTIDs that are currently in use on the server,
with the IDs of the threads that own them. This variable
is mainly useful for a multi-threaded replica to check
whether a transaction is already being applied on another
thread. An applier thread takes ownership of a
transaction's GTID all the time it is processing the
transaction, so
<code class="literal">
@@global.gtid_owned
</code>
shows the GTID and owner for the duration of processing.
When a transaction has been committed (or rolled back),
the applier thread releases ownership of the GTID.
</p>
</li>
<li class="listitem">
<p>
When used with session scope,
<a class="link" href="replication-options-gtids.html#sysvar_gtid_owned">
<code class="literal">
gtid_owned
</code>
</a>
holds a single
GTID that is currently in use by and owned by this
session. This variable is mainly useful for testing and
debugging the use of GTIDs when the client has explicitly
assigned a GTID for the transaction by setting
<a class="link" href="replication-options-gtids.html#sysvar_gtid_next">
<code class="literal">
gtid_next
</code>
</a>
. In this case,
<code class="literal">
@@session.gtid_owned
</code>
displays the GTID
all the time the client is processing the transaction,
until the transaction has been committed (or rolled back).
When the client has finished processing the transaction,
the variable is cleared. If
<a class="link" href="replication-options-gtids.html#sysvar_gtid_next">
<code class="literal">
gtid_next=AUTOMATIC
</code>
</a>
is
used for the session,
<a class="link" href="replication-options-gtids.html#sysvar_gtid_owned">
<code class="literal">
gtid_owned
</code>
</a>
is populated
only briefly during the execution of the commit statement
for the transaction, so it cannot be observed from the
session concerned, although it is listed if
<code class="literal">
@@global.gtid_owned
</code>
is read at the
right point. If you have a requirement to track the GTIDs
that are handled by a client in a session, you can enable
the session state tracker controlled by the
<a class="link" href="server-system-variables.html#sysvar_session_track_gtids">
<code class="literal">
session_track_gtids
</code>
</a>
system variable.
</p>
</li>
</ul>
</div>
</li>
<li class="listitem">
<p>
<a name="sysvar_gtid_purged">
</a>
<a class="link" href="replication-options-gtids.html#sysvar_gtid_purged">
<code class="literal">
gtid_purged
</code>
</a>
</p>
<a class="indexterm" name="idm46045138843408">
</a>
<a class="indexterm" name="idm46045138842320">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for gtid_purged">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
System Variable
</th>
<td>
<code class="literal">
<a class="link" href="replication-options-gtids.html#sysvar_gtid_purged">
gtid_purged
</a>
</code>
</td>
</tr>
<tr>
<th>
Scope
</th>
<td>
Global
</td>
</tr>
<tr>
<th>
Dynamic
</th>
<td>
Yes
</td>
</tr>
<tr>
<th>
<a class="link" href="optimizer-hints.html#optimizer-hints-set-var" title="Variable-Setting Hint Syntax">
<code class="literal">
SET_VAR
</code>
</a>
Hint Applies
</th>
<td>
No
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
String
</td>
</tr>
<tr>
<th>
Unit
</th>
<td>
set of GTIDs
</td>
</tr>
</tbody>
</table>
</div>
<p>
The global value of the
<code class="literal">
gtid_purged
</code>
system
variable (
<code class="literal">
@@GLOBAL.gtid_purged
</code>
) is a GTID
set consisting of the GTIDs of all the transactions that have
been committed on the server, but do not exist in any binary
log file on the server.
<code class="literal">
gtid_purged
</code>
is a
subset of
<a class="link" href="replication-options-gtids.html#sysvar_gtid_executed">
<code class="literal">
gtid_executed
</code>
</a>
. The
following categories of GTIDs are in
<code class="literal">
gtid_purged
</code>
:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
GTIDs of replicated transactions that were committed with
binary logging disabled on the replica.
</p>
</li>
<li class="listitem">
<p>
GTIDs of transactions that were written to a binary log
file that has now been purged.
</p>
</li>
<li class="listitem">
<p>
GTIDs that were added explicitly to the set by the
statement
<code class="literal">
SET @@GLOBAL.gtid_purged
</code>
.
</p>
</li>
</ul>
</div>
<p>
When the server starts, the global value of
<code class="literal">
gtid_purged
</code>
is initialized to a set of
GTIDs. For information on how this GTID set is computed, see
<a class="xref" href="replication-gtids-lifecycle.html#replication-gtids-gtid-purged" title="The gtid_purged System Variable">
The
<code class="literal">
gtid_purged
</code>
System Variable
</a>
. If binary
logs from MySQL 5.7.7 or older are present on the server, you
might need to set
<a class="link" href="replication-options-gtids.html#sysvar_binlog_gtid_simple_recovery">
<code class="literal">
binlog_gtid_simple_recovery=FALSE
</code>
</a>
in the server's configuration file to produce the correct
computation. See the description for
<code class="literal">
binlog_gtid_simple_recovery
</code>
for details of
the situations in which this setting is needed.
</p>
<p>
You must have the
<a class="link" href="privileges-provided.html#priv_transaction-gtid-tag">
<code class="literal">
TRANSACTION_GTID_TAG
</code>
</a>
to set
<code class="literal">
gtid_purged
</code>
.
</p>
<p>
Issuing
<a class="link" href="reset-binary-logs-and-gtids.html" title="15.4.1.2 RESET BINARY LOGS AND GTIDS Statement">
<code class="literal">
RESET BINARY LOGS AND
GTIDS
</code>
</a>
causes the value of
<code class="literal">
gtid_purged
</code>
to be reset to an empty string.
</p>
<p>
You can set the value of
<code class="literal">
gtid_purged
</code>
in
order to record on the server that the transactions in a
certain GTID set have been applied, although they do not exist
in any binary log on the server. An example use case for this
action is when you are restoring a backup of one or more
databases on a server, but you do not have the relevant binary
logs containing the transactions on the server.
</p>
<div class="important" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Important
</div>
<p>
GTIDs are only available on a server instance up to the
number of non-negative values for a signed 64-bit integer
(2
<sup>
63
</sup>
- 1). If you set the value
of
<code class="literal">
gtid_purged
</code>
to a number that
approaches this limit, subsequent commits can cause the
server to run out of GTIDs and take the action specified by
<code class="literal">
binlog_error_action
</code>
. A warning message is
issued when the server instance is approaching the limit.
</p>
</div>
<p>
There are two ways to set the value of
<code class="literal">
gtid_purged
</code>
. You can either replace the
value of
<code class="literal">
gtid_purged
</code>
with your specified
GTID set, or you can append your specified GTID set to the
GTID set that is already held by
<code class="literal">
gtid_purged
</code>
. If the server has no existing
GTIDs, for example an empty server that you are provisioning
with a backup of an existing database, both methods have the
same result. If you are restoring a backup that overlaps the
transactions that are already on the server, for example
replacing a corrupted table with a partial dump from the
source made using
<a class="link" href="mysqldump.html" title="6.5.4 mysqldump — A Database Backup Program">
<span class="command">
<strong>
mysqldump
</strong>
</span>
</a>
(which includes
the GTIDs of all the transactions on the server, even though
the dump is partial), use the first method of replacing the
value of
<code class="literal">
gtid_purged
</code>
. If you are restoring
a backup that is disjoint from the transactions that are
already on the server, for example provisioning a multi-source
replica using dumps from two different servers, use the second
method of adding to the value of
<code class="literal">
gtid_purged
</code>
.
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
To replace the value of
<code class="literal">
gtid_purged
</code>
with your specified GTID set, use the following statement:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-sql"><div class="docs-select-all right" id="sa1943981"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">SET</span> <span class="token variable">@@GLOBAL.gtid_purged</span> <span class="token operator">=</span> <span class="token string">'gtid_set'</span></code></pre>
</div>
<p>
<code class="literal">
gtid_set
</code>
must be a superset of the
current value of
<code class="literal">
gtid_purged
</code>
, and must
not intersect with
<code class="literal">
gtid_subtract(gtid_executed,gtid_purged)
</code>
.
In other words, the new GTID set
<span class="bold">
<strong>
must
</strong>
</span>
include any GTIDs
that were already in
<code class="literal">
gtid_purged
</code>
, and
<span class="bold">
<strong>
must not
</strong>
</span>
include any
GTIDs in
<a class="link" href="replication-options-gtids.html#sysvar_gtid_executed">
<code class="literal">
gtid_executed
</code>
</a>
that have not yet been purged.
<code class="literal">
gtid_set
</code>
also cannot include any GTIDs that are in
<code class="literal">
@@global.gtid_owned
</code>
, that is, the GTIDs
for transactions that are currently being processed on the
server.
</p>
<p>
The result is that the global value of
<code class="literal">
gtid_purged
</code>
is set equal to
<code class="literal">
gtid_set
</code>
, and the value of
<code class="literal">
gtid_executed
</code>
becomes the union of
<code class="literal">
gtid_set
</code>
and the previous value of
<code class="literal">
gtid_executed
</code>
.
</p>
</li>
<li class="listitem">
<p>
To append your specified GTID set to
<code class="literal">
gtid_purged
</code>
, use the following
statement with a plus sign (+) before the GTID set:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-sql"><div class="docs-select-all right" id="sa84477973"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">SET</span> <span class="token variable">@@GLOBAL.gtid_purged</span> <span class="token operator">=</span> <span class="token string">'+gtid_set'</span></code></pre>
</div>
<p>
<code class="literal">
gtid_set
</code>
<span class="bold">
<strong>
must
not
</strong>
</span>
intersect with the current value of
<code class="literal">
gtid_executed
</code>
. In other words, the new
GTID set must not include any GTIDs in
<code class="literal">
gtid_executed
</code>
, including transactions
that are already also in
<code class="literal">
gtid_purged
</code>
.
<code class="literal">
gtid_set
</code>
also cannot include any GTIDs
that are in
<code class="literal">
@@global.gtid_owned
</code>
, that
is, the GTIDs for transactions that are currently being
processed on the server.
</p>
<p>
The result is that
<code class="literal">
gtid_set
</code>
is added to
both
<code class="literal">
gtid_executed
</code>
and
<code class="literal">
gtid_purged
</code>
.
</p>
</li>
</ul>
</div>
</li>
</ul>
</div>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Note
</div>
<p>
If any binary logs from MySQL 5.7.7 or older are present on the
server (for example, following an upgrade of an older server to
MySQL 8.4), after issuing a
<code class="literal">
SET
@@GLOBAL.gtid_purged
</code>
statement, you might need to set
<a class="link" href="replication-options-gtids.html#sysvar_binlog_gtid_simple_recovery">
<code class="literal">
binlog_gtid_simple_recovery=FALSE
</code>
</a>
in the server's configuration file before restarting the server,
otherwise
<code class="literal">
gtid_purged
</code>
can be computed
incorrectly. See the description for
<code class="literal">
binlog_gtid_simple_recovery
</code>
for details of
the situations in which this setting is needed.
</p>
</div>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/alter-logfile-group.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="alter-logfile-group">
</a>
15.1.6 ALTER LOGFILE GROUP Statement
</h3>
</div>
</div>
</div>
<a class="indexterm" name="idm46045189664368">
</a>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa73228654"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">ALTER</span> <span class="token keyword">LOGFILE</span> <span class="token keyword">GROUP</span> <em class="replaceable">logfile_group</em>
<span class="token keyword">ADD</span> <span class="token keyword">UNDOFILE</span> <span class="token string">'<em class="replaceable">file_name</em>'</span>
<span class="token punctuation">[</span><span class="token keyword">INITIAL_SIZE</span> <span class="token punctuation">[</span><span class="token operator">=</span><span class="token punctuation">]</span> <em class="replaceable">size</em><span class="token punctuation">]</span>
<span class="token punctuation">[</span><span class="token keyword">WAIT</span><span class="token punctuation">]</span>
<span class="token keyword">ENGINE</span> <span class="token punctuation">[</span><span class="token operator">=</span><span class="token punctuation">]</span> <em class="replaceable">engine_name</em></code></pre>
</div>
<p>
This statement adds an
<code class="literal">
UNDO
</code>
file named
'
<em class="replaceable">
<code>
file_name
</code>
</em>
' to an existing log file
group
<em class="replaceable">
<code>
logfile_group
</code>
</em>
. An
<a class="link" href="alter-logfile-group.html" title="15.1.6 ALTER LOGFILE GROUP Statement">
<code class="literal">
ALTER LOGFILE GROUP
</code>
</a>
statement has
one and only one
<code class="literal">
ADD UNDOFILE
</code>
clause. No
<code class="literal">
DROP UNDOFILE
</code>
clause is currently supported.
</p>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Note
</div>
<p>
All NDB Cluster Disk Data objects share the same namespace. This
means that
<span class="emphasis">
<em>
each Disk Data object
</em>
</span>
must be
uniquely named (and not merely each Disk Data object of a given
type). For example, you cannot have a tablespace and an undo log
file with the same name, or an undo log file and a data file
with the same name.
</p>
</div>
<p>
The optional
<code class="literal">
INITIAL_SIZE
</code>
parameter sets the
<code class="literal">
UNDO
</code>
file's initial size in bytes; if not
specified, the initial size defaults to 134217728 (128 MB). You
may optionally follow
<em class="replaceable">
<code>
size
</code>
</em>
with a
one-letter abbreviation for an order of magnitude, similar to
those used in
<code class="filename">
my.cnf
</code>
. Generally, this is one
of the letters
<code class="literal">
M
</code>
(megabytes) or
<code class="literal">
G
</code>
(gigabytes). (Bug #13116514, Bug #16104705,
Bug #62858)
</p>
<p>
On 32-bit systems, the maximum supported value for
<code class="literal">
INITIAL_SIZE
</code>
is 4294967296 (4 GB). (Bug #29186)
</p>
<p>
The minimum allowed value for
<code class="literal">
INITIAL_SIZE
</code>
is
1048576 (1 MB). (Bug #29574)
</p>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Note
</div>
<p>
<code class="literal">
WAIT
</code>
is parsed but otherwise ignored. This
keyword currently has no effect, and is intended for future
expansion.
</p>
</div>
<p>
The
<code class="literal">
ENGINE
</code>
clause (required) determines the
storage engine which is used by this log file group, with
<em class="replaceable">
<code>
engine_name
</code>
</em>
being the name of the
storage engine. Currently, the only accepted values for
<em class="replaceable">
<code>
engine_name
</code>
</em>
are
<span class="quote">
“
<span class="quote">
<a class="link" href="mysql-cluster.html" title="Chapter 25 MySQL NDB Cluster 8.4">
<code class="literal">
NDBCLUSTER
</code>
</a>
</span>
”
</span>
and
<span class="quote">
“
<span class="quote">
<a class="link" href="mysql-cluster.html" title="Chapter 25 MySQL NDB Cluster 8.4">
<code class="literal">
NDB
</code>
</a>
</span>
”
</span>
. The two values
are equivalent.
</p>
<p>
Here is an example, which assumes that the log file group
<code class="literal">
lg_3
</code>
has already been created using
<a class="link" href="create-logfile-group.html" title="15.1.16 CREATE LOGFILE GROUP Statement">
<code class="literal">
CREATE LOGFILE GROUP
</code>
</a>
(see
<a class="xref" href="create-logfile-group.html" title="15.1.16 CREATE LOGFILE GROUP Statement">
Section 15.1.16, “CREATE LOGFILE GROUP Statement”
</a>
):
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa99342914"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">ALTER</span> <span class="token keyword">LOGFILE</span> <span class="token keyword">GROUP</span> lg_3
<span class="token keyword">ADD</span> <span class="token keyword">UNDOFILE</span> <span class="token string">'undo_10.dat'</span>
<span class="token keyword">INITIAL_SIZE</span><span class="token operator">=</span>32M
<span class="token keyword">ENGINE</span><span class="token operator">=</span><span class="token keyword">NDBCLUSTER</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
When
<a class="link" href="alter-logfile-group.html" title="15.1.6 ALTER LOGFILE GROUP Statement">
<code class="literal">
ALTER LOGFILE GROUP
</code>
</a>
is used
with
<code class="literal">
ENGINE = NDBCLUSTER
</code>
(alternatively,
<code class="literal">
ENGINE = NDB
</code>
), an undo log file is created on
each NDB Cluster data node. You can verify that the undo files
were created and obtain information about them by querying the
Information Schema
<a class="link" href="information-schema-files-table.html" title="28.3.15 The INFORMATION_SCHEMA FILES Table">
<code class="literal">
FILES
</code>
</a>
table. For
example:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa1866070"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> FILE_NAME<span class="token punctuation">,</span> LOGFILE_GROUP_NUMBER<span class="token punctuation">,</span> EXTRA
<span class="token prompt"> -></span> <span class="token keyword">FROM</span> INFORMATION_SCHEMA<span class="token punctuation">.</span>FILES
<span class="token prompt"> -></span> <span class="token keyword">WHERE</span> LOGFILE_GROUP_NAME <span class="token operator">=</span> <span class="token string">'lg_3'</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> FILE_NAME <span class="token punctuation">|</span> LOGFILE_GROUP_NUMBER <span class="token punctuation">|</span> EXTRA <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> newdata.dat <span class="token punctuation">|</span> 0 <span class="token punctuation">|</span> CLUSTER_NODE=3 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> newdata.dat <span class="token punctuation">|</span> 0 <span class="token punctuation">|</span> CLUSTER_NODE=4 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> undo_10.dat <span class="token punctuation">|</span> 11 <span class="token punctuation">|</span> CLUSTER_NODE=3 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> undo_10.dat <span class="token punctuation">|</span> 11 <span class="token punctuation">|</span> CLUSTER_NODE=4 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output">4 rows in set (0.01 sec)</span></code></pre>
</div>
<p>
(See
<a class="xref" href="information-schema-files-table.html" title="28.3.15 The INFORMATION_SCHEMA FILES Table">
Section 28.3.15, “The INFORMATION_SCHEMA FILES Table”
</a>
.)
</p>
<p>
Memory used for
<code class="literal">
UNDO_BUFFER_SIZE
</code>
comes from the
global pool whose size is determined by the value of the
<a class="link" href="mysql-cluster-ndbd-definition.html#ndbparam-ndbd-sharedglobalmemory">
<code class="literal">
SharedGlobalMemory
</code>
</a>
data
node configuration parameter. This includes any default value
implied for this option by the setting of the
<a class="link" href="mysql-cluster-ndbd-definition.html#ndbparam-ndbd-initiallogfilegroup">
<code class="literal">
InitialLogFileGroup
</code>
</a>
data
node configuration parameter.
</p>
<p>
<a class="link" href="alter-logfile-group.html" title="15.1.6 ALTER LOGFILE GROUP Statement">
<code class="literal">
ALTER LOGFILE GROUP
</code>
</a>
is useful only
with Disk Data storage for NDB Cluster. For more information, see
<a class="xref" href="mysql-cluster-disk-data.html" title="25.6.11 NDB Cluster Disk Data Tables">
Section 25.6.11, “NDB Cluster Disk Data Tables”
</a>
.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/implicit-commit.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="implicit-commit">
</a>
15.3.3 Statements That Cause an Implicit Commit
</h3>
</div>
</div>
</div>
<p>
The statements listed in this section (and any synonyms for them)
implicitly end any transaction active in the current session, as
if you had done a
<a class="link" href="commit.html" title="15.3.1 START TRANSACTION, COMMIT, and ROLLBACK Statements">
<code class="literal">
COMMIT
</code>
</a>
before
executing the statement.
</p>
<p>
Most of these statements also cause an implicit commit after
executing. The intent is to handle each such statement in its own
special transaction. Transaction-control and locking statements
are exceptions: If an implicit commit occurs before execution,
another does not occur after.
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<span class="bold">
<strong>
Data definition language (DDL)
statements that define or modify database objects.
</strong>
</span>
<a class="link" href="alter-event.html" title="15.1.3 ALTER EVENT Statement">
<code class="literal">
ALTER EVENT
</code>
</a>
,
<a class="link" href="alter-function.html" title="15.1.4 ALTER FUNCTION Statement">
<code class="literal">
ALTER FUNCTION
</code>
</a>
,
<a class="link" href="alter-procedure.html" title="15.1.7 ALTER PROCEDURE Statement">
<code class="literal">
ALTER PROCEDURE
</code>
</a>
,
<a class="link" href="alter-server.html" title="15.1.8 ALTER SERVER Statement">
<code class="literal">
ALTER SERVER
</code>
</a>
,
<a class="link" href="alter-table.html" title="15.1.9 ALTER TABLE Statement">
<code class="literal">
ALTER TABLE
</code>
</a>
,
<a class="link" href="alter-tablespace.html" title="15.1.10 ALTER TABLESPACE Statement">
<code class="literal">
ALTER TABLESPACE
</code>
</a>
,
<a class="link" href="alter-view.html" title="15.1.11 ALTER VIEW Statement">
<code class="literal">
ALTER VIEW
</code>
</a>
,
<a class="link" href="create-database.html" title="15.1.12 CREATE DATABASE Statement">
<code class="literal">
CREATE DATABASE
</code>
</a>
,
<a class="link" href="create-event.html" title="15.1.13 CREATE EVENT Statement">
<code class="literal">
CREATE EVENT
</code>
</a>
,
<a class="link" href="create-function.html" title="15.1.14 CREATE FUNCTION Statement">
<code class="literal">
CREATE FUNCTION
</code>
</a>
,
<a class="link" href="create-index.html" title="15.1.15 CREATE INDEX Statement">
<code class="literal">
CREATE INDEX
</code>
</a>
,
<a class="link" href="create-procedure.html" title="15.1.17 CREATE PROCEDURE and CREATE FUNCTION Statements">
<code class="literal">
CREATE PROCEDURE
</code>
</a>
,
<a class="link" href="create-role.html" title="15.7.1.2 CREATE ROLE Statement">
<code class="literal">
CREATE ROLE
</code>
</a>
,
<a class="link" href="create-server.html" title="15.1.18 CREATE SERVER Statement">
<code class="literal">
CREATE SERVER
</code>
</a>
,
<a class="link" href="create-spatial-reference-system.html" title="15.1.19 CREATE SPATIAL REFERENCE SYSTEM Statement">
<code class="literal">
CREATE SPATIAL REFERENCE
SYSTEM
</code>
</a>
,
<a class="link" href="create-table.html" title="15.1.20 CREATE TABLE Statement">
<code class="literal">
CREATE TABLE
</code>
</a>
,
<a class="link" href="create-tablespace.html" title="15.1.21 CREATE TABLESPACE Statement">
<code class="literal">
CREATE TABLESPACE
</code>
</a>
,
<a class="link" href="create-trigger.html" title="15.1.22 CREATE TRIGGER Statement">
<code class="literal">
CREATE TRIGGER
</code>
</a>
,
<a class="link" href="create-view.html" title="15.1.23 CREATE VIEW Statement">
<code class="literal">
CREATE VIEW
</code>
</a>
,
<a class="link" href="drop-database.html" title="15.1.24 DROP DATABASE Statement">
<code class="literal">
DROP DATABASE
</code>
</a>
,
<a class="link" href="drop-event.html" title="15.1.25 DROP EVENT Statement">
<code class="literal">
DROP EVENT
</code>
</a>
,
<a class="link" href="drop-function.html" title="15.1.26 DROP FUNCTION Statement">
<code class="literal">
DROP FUNCTION
</code>
</a>
,
<a class="link" href="drop-index.html" title="15.1.27 DROP INDEX Statement">
<code class="literal">
DROP INDEX
</code>
</a>
,
<a class="link" href="drop-procedure.html" title="15.1.29 DROP PROCEDURE and DROP FUNCTION Statements">
<code class="literal">
DROP PROCEDURE
</code>
</a>
,
<a class="link" href="drop-role.html" title="15.7.1.4 DROP ROLE Statement">
<code class="literal">
DROP ROLE
</code>
</a>
,
<a class="link" href="drop-server.html" title="15.1.30 DROP SERVER Statement">
<code class="literal">
DROP SERVER
</code>
</a>
,
<a class="link" href="drop-spatial-reference-system.html" title="15.1.31 DROP SPATIAL REFERENCE SYSTEM Statement">
<code class="literal">
DROP SPATIAL REFERENCE SYSTEM
</code>
</a>
,
<a class="link" href="drop-table.html" title="15.1.32 DROP TABLE Statement">
<code class="literal">
DROP TABLE
</code>
</a>
,
<a class="link" href="drop-tablespace.html" title="15.1.33 DROP TABLESPACE Statement">
<code class="literal">
DROP TABLESPACE
</code>
</a>
,
<a class="link" href="drop-trigger.html" title="15.1.34 DROP TRIGGER Statement">
<code class="literal">
DROP TRIGGER
</code>
</a>
,
<a class="link" href="drop-view.html" title="15.1.35 DROP VIEW Statement">
<code class="literal">
DROP VIEW
</code>
</a>
,
<a class="link" href="install-plugin.html" title="15.7.4.4 INSTALL PLUGIN Statement">
<code class="literal">
INSTALL PLUGIN
</code>
</a>
,
<a class="link" href="rename-table.html" title="15.1.36 RENAME TABLE Statement">
<code class="literal">
RENAME TABLE
</code>
</a>
,
<a class="link" href="truncate-table.html" title="15.1.37 TRUNCATE TABLE Statement">
<code class="literal">
TRUNCATE TABLE
</code>
</a>
,
<a class="link" href="uninstall-plugin.html" title="15.7.4.6 UNINSTALL PLUGIN Statement">
<code class="literal">
UNINSTALL PLUGIN
</code>
</a>
.
</p>
<p>
<a class="link" href="create-table.html" title="15.1.20 CREATE TABLE Statement">
<code class="literal">
CREATE TABLE
</code>
</a>
and
<a class="link" href="drop-table.html" title="15.1.32 DROP TABLE Statement">
<code class="literal">
DROP TABLE
</code>
</a>
statements do not
commit a transaction if the
<code class="literal">
TEMPORARY
</code>
keyword is used. (This does not apply to other operations on
temporary tables such as
<a class="link" href="alter-table.html" title="15.1.9 ALTER TABLE Statement">
<code class="literal">
ALTER
TABLE
</code>
</a>
and
<a class="link" href="create-index.html" title="15.1.15 CREATE INDEX Statement">
<code class="literal">
CREATE
INDEX
</code>
</a>
, which do cause a commit.) However, although
no implicit commit occurs, neither can the statement be rolled
back, which means that the use of such statements causes
transactional atomicity to be violated. For example, if you
use
<a class="link" href="create-table.html" title="15.1.20 CREATE TABLE Statement">
<code class="literal">
CREATE
TEMPORARY TABLE
</code>
</a>
and then roll back the transaction,
the table remains in existence.
</p>
<p>
The
<a class="link" href="create-table.html" title="15.1.20 CREATE TABLE Statement">
<code class="literal">
CREATE TABLE
</code>
</a>
statement in
<code class="literal">
InnoDB
</code>
is processed as a single
transaction. This means that a
<a class="link" href="commit.html" title="15.3.1 START TRANSACTION, COMMIT, and ROLLBACK Statements">
<code class="literal">
ROLLBACK
</code>
</a>
from the user does not undo
<a class="link" href="create-table.html" title="15.1.20 CREATE TABLE Statement">
<code class="literal">
CREATE
TABLE
</code>
</a>
statements the user made during that
transaction.
</p>
<p>
<a class="link" href="create-table.html" title="15.1.20 CREATE TABLE Statement">
<code class="literal">
CREATE TABLE ...
SELECT
</code>
</a>
causes an implicit commit before and after
the statement is executed when you are creating nontemporary
tables. (No commit occurs for
<code class="literal">
CREATE TEMPORARY TABLE
... SELECT
</code>
.)
</p>
</li>
<li class="listitem">
<p>
<span class="bold">
<strong>
Statements that implicitly use or modify
tables in the
<code class="literal">
mysql
</code>
database.
</strong>
</span>
<a class="link" href="alter-user.html" title="15.7.1.1 ALTER USER Statement">
<code class="literal">
ALTER USER
</code>
</a>
,
<a class="link" href="create-user.html" title="15.7.1.3 CREATE USER Statement">
<code class="literal">
CREATE USER
</code>
</a>
,
<a class="link" href="drop-user.html" title="15.7.1.5 DROP USER Statement">
<code class="literal">
DROP USER
</code>
</a>
,
<a class="link" href="grant.html" title="15.7.1.6 GRANT Statement">
<code class="literal">
GRANT
</code>
</a>
,
<a class="link" href="rename-user.html" title="15.7.1.7 RENAME USER Statement">
<code class="literal">
RENAME USER
</code>
</a>
,
<a class="link" href="revoke.html" title="15.7.1.8 REVOKE Statement">
<code class="literal">
REVOKE
</code>
</a>
,
<a class="link" href="set-password.html" title="15.7.1.10 SET PASSWORD Statement">
<code class="literal">
SET PASSWORD
</code>
</a>
.
</p>
</li>
<li class="listitem">
<p>
<span class="bold">
<strong>
Transaction-control and locking
statements.
</strong>
</span>
<a class="link" href="commit.html" title="15.3.1 START TRANSACTION, COMMIT, and ROLLBACK Statements">
<code class="literal">
BEGIN
</code>
</a>
,
<a class="link" href="lock-tables.html" title="15.3.6 LOCK TABLES and UNLOCK TABLES Statements">
<code class="literal">
LOCK TABLES
</code>
</a>
,
<code class="literal">
SET
autocommit = 1
</code>
(if the value is not already 1),
<a class="link" href="commit.html" title="15.3.1 START TRANSACTION, COMMIT, and ROLLBACK Statements">
<code class="literal">
START
TRANSACTION
</code>
</a>
,
<a class="link" href="lock-tables.html" title="15.3.6 LOCK TABLES and UNLOCK TABLES Statements">
<code class="literal">
UNLOCK
TABLES
</code>
</a>
.
</p>
<p>
<a class="link" href="lock-tables.html" title="15.3.6 LOCK TABLES and UNLOCK TABLES Statements">
<code class="literal">
UNLOCK
TABLES
</code>
</a>
commits a transaction only if any tables
currently have been locked with
<a class="link" href="lock-tables.html" title="15.3.6 LOCK TABLES and UNLOCK TABLES Statements">
<code class="literal">
LOCK
TABLES
</code>
</a>
to acquire nontransactional table locks. A
commit does not occur for
<a class="link" href="lock-tables.html" title="15.3.6 LOCK TABLES and UNLOCK TABLES Statements">
<code class="literal">
UNLOCK
TABLES
</code>
</a>
following
<a class="link" href="flush.html#flush-tables-with-read-lock">
<code class="literal">
FLUSH TABLES
WITH READ LOCK
</code>
</a>
because the latter statement does not
acquire table-level locks.
</p>
<p>
Transactions cannot be nested. This is a consequence of the
implicit commit performed for any current transaction when you
issue a
<a class="link" href="commit.html" title="15.3.1 START TRANSACTION, COMMIT, and ROLLBACK Statements">
<code class="literal">
START
TRANSACTION
</code>
</a>
statement or one of its synonyms.
</p>
<p>
Statements that cause an implicit commit cannot be used in an
XA transaction while the transaction is in an
<code class="literal">
ACTIVE
</code>
state.
</p>
<p>
The
<a class="link" href="commit.html" title="15.3.1 START TRANSACTION, COMMIT, and ROLLBACK Statements">
<code class="literal">
BEGIN
</code>
</a>
statement differs from the use of the
<code class="literal">
BEGIN
</code>
keyword that starts a
<a class="link" href="begin-end.html" title="15.6.1 BEGIN ... END Compound Statement">
<code class="literal">
BEGIN ...
END
</code>
</a>
compound statement. The latter does not cause an
implicit commit. See
<a class="xref" href="begin-end.html" title="15.6.1 BEGIN ... END Compound Statement">
Section 15.6.1, “BEGIN ... END Compound Statement”
</a>
.
</p>
</li>
<li class="listitem">
<p>
<span class="bold">
<strong>
Data loading statements.
</strong>
</span>
<a class="link" href="load-data.html" title="15.2.9 LOAD DATA Statement">
<code class="literal">
LOAD DATA
</code>
</a>
.
<a class="link" href="load-data.html" title="15.2.9 LOAD DATA Statement">
<code class="literal">
LOAD DATA
</code>
</a>
causes an implicit
commit only for tables using the
<a class="link" href="mysql-cluster.html" title="Chapter 25 MySQL NDB Cluster 8.4">
<code class="literal">
NDB
</code>
</a>
storage engine.
</p>
</li>
<li class="listitem">
<p>
<span class="bold">
<strong>
Administrative statements.
</strong>
</span>
<a class="link" href="analyze-table.html" title="15.7.3.1 ANALYZE TABLE Statement">
<code class="literal">
ANALYZE TABLE
</code>
</a>
,
<a class="link" href="cache-index.html" title="15.7.8.2 CACHE INDEX Statement">
<code class="literal">
CACHE INDEX
</code>
</a>
,
<a class="link" href="check-table.html" title="15.7.3.2 CHECK TABLE Statement">
<code class="literal">
CHECK TABLE
</code>
</a>
,
<a class="link" href="flush.html" title="15.7.8.3 FLUSH Statement">
<code class="literal">
FLUSH
</code>
</a>
,
<a class="link" href="load-index.html" title="15.7.8.5 LOAD INDEX INTO CACHE Statement">
<code class="literal">
LOAD INDEX INTO
CACHE
</code>
</a>
,
<a class="link" href="optimize-table.html" title="15.7.3.4 OPTIMIZE TABLE Statement">
<code class="literal">
OPTIMIZE
TABLE
</code>
</a>
,
<a class="link" href="repair-table.html" title="15.7.3.5 REPAIR TABLE Statement">
<code class="literal">
REPAIR TABLE
</code>
</a>
,
<a class="link" href="reset.html" title="15.7.8.6 RESET Statement">
<code class="literal">
RESET
</code>
</a>
(but not
<a class="link" href="reset-persist.html" title="15.7.8.7 RESET PERSIST Statement">
<code class="literal">
RESET PERSIST
</code>
</a>
).
</p>
</li>
<li class="listitem">
<p>
<span class="bold">
<strong>
Replication control
statements
</strong>
</span>
.
<a class="link" href="start-replica.html" title="15.4.2.4 START REPLICA Statement">
<code class="literal">
START
REPLICA
</code>
</a>
,
<a class="link" href="stop-replica.html" title="15.4.2.5 STOP REPLICA Statement">
<code class="literal">
STOP
REPLICA
</code>
</a>
,
<a class="link" href="reset-replica.html" title="15.4.2.3 RESET REPLICA Statement">
<code class="literal">
RESET
REPLICA
</code>
</a>
,
<a class="link" href="change-replication-source-to.html" title="15.4.2.2 CHANGE REPLICATION SOURCE TO Statement">
<code class="literal">
CHANGE REPLICATION
SOURCE TO
</code>
</a>
.
</p>
</li>
</ul>
</div>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/command-line-options.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="command-line-options">
</a>
6.2.2.1 Using Options on the Command Line
</h4>
</div>
</div>
</div>
<p>
Program options specified on the command line follow these
rules:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
Options are given after the command name.
</p>
</li>
<li class="listitem">
<p>
An option argument begins with one dash or two dashes,
depending on whether it is a short form or long form of the
option name. Many options have both short and long forms.
For example,
<code class="option">
-?
</code>
and
<code class="option">
--help
</code>
are the short and long forms of the option that instructs a
MySQL program to display its help message.
</p>
</li>
<li class="listitem">
<p>
Option names are case-sensitive.
<code class="option">
-v
</code>
and
<code class="option">
-V
</code>
are both legal and have different
meanings. (They are the corresponding short forms of the
<code class="option">
--verbose
</code>
and
<code class="option">
--version
</code>
options.)
</p>
</li>
<li class="listitem">
<p>
Some options take a value following the option name. For
example,
<code class="option">
-h localhost
</code>
or
<a class="link" href="connection-options.html#option_general_host">
<code class="option">
--host=localhost
</code>
</a>
indicate
the MySQL server host to a client program. The option value
tells the program the name of the host where the MySQL
server is running.
</p>
</li>
<li class="listitem">
<p>
For a long option that takes a value, separate the option
name and the value by an
<code class="literal">
=
</code>
sign. For a
short option that takes a value, the option value can
immediately follow the option letter, or there can be a
space between:
<code class="option">
-hlocalhost
</code>
and
<code class="option">
-h
localhost
</code>
are equivalent. An exception to this rule
is the option for specifying your MySQL password. This
option can be given in long form as
<a class="link" href="connection-options.html#option_general_password">
<code class="option">
--password=
<em class="replaceable">
<code>
pass_val
</code>
</em>
</code>
</a>
or as
<a class="link" href="connection-options.html#option_general_password">
<code class="option">
--password
</code>
</a>
. In the
latter case (with no password value given), the program
interactively prompts you for the password. The password
option also may be given in short form as
<code class="option">
-p
<em class="replaceable">
<code>
pass_val
</code>
</em>
</code>
or as
<code class="option">
-p
</code>
. However, for the short form, if the
password value is given, it must follow the option letter
with
<span class="emphasis">
<em>
no intervening space
</em>
</span>
: If a space
follows the option letter, the program has no way to tell
whether a following argument is supposed to be the password
value or some other kind of argument. Consequently, the
following two commands have two completely different
meanings:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-terminal"><div class="docs-select-all right" id="sa72940878"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal">mysql <span class="token property">-ptest</span>
mysql <span class="token property">-p</span> test</code></pre>
</div>
<p>
The first command instructs
<a class="link" href="mysql.html" title="6.5.1 mysql — The MySQL Command-Line Client">
<span class="command">
<strong>
mysql
</strong>
</span>
</a>
to use
a password value of
<code class="literal">
test
</code>
, but specifies
no default database. The second instructs
<a class="link" href="mysql.html" title="6.5.1 mysql — The MySQL Command-Line Client">
<span class="command">
<strong>
mysql
</strong>
</span>
</a>
to prompt for the password value
and to use
<code class="literal">
test
</code>
as the default database.
</p>
</li>
<li class="listitem">
<p>
Within option names, dash (
<code class="literal">
-
</code>
) and
underscore (
<code class="literal">
_
</code>
) may be used
interchangeably in most cases, although the leading dashes
<span class="emphasis">
<em>
cannot
</em>
</span>
be given as underscores. For
example,
<a class="link" href="server-options.html#option_mysqld_skip-grant-tables">
<code class="option">
--skip-grant-tables
</code>
</a>
and
<a class="link" href="server-options.html#option_mysqld_skip-grant-tables">
<code class="option">
--skip_grant_tables
</code>
</a>
are equivalent.
</p>
<p>
In this Manual, we use dashes in option names, except where
underscores are significant. This is the case with, for
example,
<a class="link" href="replication-options-binary-log.html#option_mysqld_log-bin">
<code class="option">
--log-bin
</code>
</a>
and
<a class="link" href="replication-options-binary-log.html#sysvar_log_bin">
<code class="option">
--log_bin
</code>
</a>
, which are
different options. We encourage you to do so as well.
</p>
</li>
<li class="listitem">
<p>
The MySQL server has certain command options that may be
specified only at startup, and a set of system variables,
some of which may be set at startup, at runtime, or both.
System variable names use underscores rather than dashes,
and when referenced at runtime (for example, using
<a class="link" href="set-variable.html" title="15.7.6.1 SET Syntax for Variable Assignment">
<code class="literal">
SET
</code>
</a>
or
<a class="link" href="select.html" title="15.2.13 SELECT Statement">
<code class="literal">
SELECT
</code>
</a>
statements), must
be written using underscores:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa79597969"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">SET</span> <span class="token keyword">GLOBAL</span> general_log <span class="token operator">=</span> <span class="token keyword">ON</span><span class="token punctuation">;</span>
<span class="token keyword">SELECT</span> <span class="token variable">@@GLOBAL.general_log</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
At server startup, the syntax for system variables is the
same as for command options, so within variable names,
dashes and underscores may be used interchangeably. For
example,
<a class="link" href="server-system-variables.html#sysvar_general_log">
<code class="option">
--general_log=ON
</code>
</a>
and
<a class="link" href="server-system-variables.html#sysvar_general_log">
<code class="option">
--general-log=ON
</code>
</a>
are
equivalent. (This is also true for system variables set
within option files.)
</p>
</li>
<li class="listitem">
<p>
For options that take a numeric value, the value can be
given with a suffix of
<code class="literal">
K
</code>
,
<code class="literal">
M
</code>
, or
<code class="literal">
G
</code>
to indicate a
multiplier of 1024, 1024
<sup>
2
</sup>
or
1024
<sup>
3
</sup>
. As of MySQL 8.0.14, a
suffix can also be
<code class="literal">
T
</code>
,
<code class="literal">
P
</code>
, and
<code class="literal">
E
</code>
to indicate a
multiplier of 1024
<sup>
4
</sup>
,
1024
<sup>
5
</sup>
or
1024
<sup>
6
</sup>
. Suffix letters can be
uppercase or lowercase.
</p>
<p>
For example, the following command tells
<a class="link" href="mysqladmin.html" title="6.5.2 mysqladmin — A MySQL Server Administration Program">
<span class="command">
<strong>
mysqladmin
</strong>
</span>
</a>
to ping the server 1024 times,
sleeping 10 seconds between each ping:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-terminal"><div class="docs-select-all right" id="sa79298565"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal">mysqladmin <span class="token constant">--count</span><span class="token attr-value"><span class="token punctuation">=</span>1K</span> <span class="token constant">--sleep</span><span class="token attr-value"><span class="token punctuation">=</span>10</span> ping</code></pre>
</div>
</li>
<li class="listitem">
<p>
When specifying file names as option values, avoid the use
of the
<code class="literal">
~
</code>
shell metacharacter. It might
not be interpreted as you expect.
</p>
</li>
</ul>
</div>
<p>
Option values that contain spaces must be quoted when given on
the command line. For example, the
<a class="link" href="mysql-command-options.html#option_mysql_execute">
<code class="option">
--execute
</code>
</a>
(or
<code class="option">
-e
</code>
)
option can be used with
<a class="link" href="mysql.html" title="6.5.1 mysql — The MySQL Command-Line Client">
<span class="command">
<strong>
mysql
</strong>
</span>
</a>
to pass one or
more semicolon-separated SQL statements to the server. When this
option is used,
<a class="link" href="mysql.html" title="6.5.1 mysql — The MySQL Command-Line Client">
<span class="command">
<strong>
mysql
</strong>
</span>
</a>
executes the statements
in the option value and exits. The statements must be enclosed
by quotation marks. For example:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-terminal"><div class="docs-select-all right" id="sa89158189"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal"><span class="token prompt">$> </span><span class="token command">mysql</span> <span class="token property">-u</span> root <span class="token property">-p</span> <span class="token property">-e</span> <span class="token atrule">"SELECT VERSION();SELECT NOW()"</span>
Enter password<span class="token punctuation">:</span> ******
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> VERSION() <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> 8.0.19 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> NOW() <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> 2019<span class="token punctuation">-</span>09<span class="token punctuation">-</span>03 10:36:48 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
$></code></pre>
</div>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Note
</div>
<p>
The long form (
<a class="link" href="mysql-command-options.html#option_mysql_execute">
<code class="option">
--execute
</code>
</a>
) is
followed by an equal sign (
<code class="literal">
=
</code>
).
</p>
</div>
<p>
To use quoted values within a statement, you must either escape
the inner quotation marks, or use a different type of quotation
marks within the statement from those used to quote the
statement itself. The capabilities of your command processor
dictate your choices for whether you can use single or double
quotation marks and the syntax for escaping quote characters.
For example, if your command processor supports quoting with
single or double quotation marks, you can use double quotation
marks around the statement, and single quotation marks for any
quoted values within the statement.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-programs-ndb-import.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="mysql-cluster-programs-ndb-import">
</a>
25.5.13 ndb_import — Import CSV Data Into NDB
</h3>
</div>
</div>
</div>
<a class="indexterm" name="idm46045103063952">
</a>
<p>
<a class="link" href="mysql-cluster-programs-ndb-import.html" title="25.5.13 ndb_import — Import CSV Data Into NDB">
<span class="command">
<strong>
ndb_import
</strong>
</span>
</a>
imports CSV-formatted data, such
as that produced by
<a class="link" href="mysqldump.html" title="6.5.4 mysqldump — A Database Backup Program">
<span class="command">
<strong>
mysqldump
</strong>
</span>
</a>
<a class="link" href="mysqldump.html#option_mysqldump_tab">
<code class="option">
--tab
</code>
</a>
, directly into
<code class="literal">
NDB
</code>
using the NDB API.
<a class="link" href="mysql-cluster-programs-ndb-import.html" title="25.5.13 ndb_import — Import CSV Data Into NDB">
<span class="command">
<strong>
ndb_import
</strong>
</span>
</a>
requires a connection to an NDB
management server (
<a class="link" href="mysql-cluster-programs-ndb-mgmd.html" title="25.5.4 ndb_mgmd — The NDB Cluster Management Server Daemon">
<span class="command">
<strong>
ndb_mgmd
</strong>
</span>
</a>
) to function; it
does not require a connection to a MySQL Server.
</p>
<h4>
<a name="idm46045103055536">
</a>
Usage
</h4>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-terminal"><div class="docs-select-all right" id="sa75899383"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal">ndb_import <em class="replaceable">db_name</em> <em class="replaceable">file_name</em> <em class="replaceable">options</em></code></pre>
</div>
<p>
<a class="link" href="mysql-cluster-programs-ndb-import.html" title="25.5.13 ndb_import — Import CSV Data Into NDB">
<span class="command">
<strong>
ndb_import
</strong>
</span>
</a>
requires two arguments.
<em class="replaceable">
<code>
db_name
</code>
</em>
is the name of the database
where the table into which to import the data is found;
<em class="replaceable">
<code>
file_name
</code>
</em>
is the name of the CSV file
from which to read the data; this must include the path to this
file if it is not in the current directory. The name of the file
must match that of the table; the file's extension, if any,
is not taken into consideration. Options supported by
<a class="link" href="mysql-cluster-programs-ndb-import.html" title="25.5.13 ndb_import — Import CSV Data Into NDB">
<span class="command">
<strong>
ndb_import
</strong>
</span>
</a>
include those for specifying field
separators, escapes, and line terminators, and are described
later in this section.
</p>
<p>
<a class="link" href="mysql-cluster-programs-ndb-import.html" title="25.5.13 ndb_import — Import CSV Data Into NDB">
<span class="command">
<strong>
ndb_import
</strong>
</span>
</a>
rejects any empty lines which it
reads from the CSV file, except when importing a single column,
in which case an empty value can be used as the column value.
<a class="link" href="mysql-cluster-programs-ndb-import.html" title="25.5.13 ndb_import — Import CSV Data Into NDB">
<span class="command">
<strong>
ndb_import
</strong>
</span>
</a>
handles this in the same manner as
a
<a class="link" href="load-data.html" title="15.2.9 LOAD DATA Statement">
<code class="literal">
LOAD DATA
</code>
</a>
statement does.
</p>
<p>
<a class="link" href="mysql-cluster-programs-ndb-import.html" title="25.5.13 ndb_import — Import CSV Data Into NDB">
<span class="command">
<strong>
ndb_import
</strong>
</span>
</a>
must be able to connect to an NDB
Cluster management server; for this reason, there must be an
unused
<code class="literal">
[api]
</code>
slot in the cluster
<code class="filename">
config.ini
</code>
file.
</p>
<p>
To duplicate an existing table that uses a different storage
engine, such as
<a class="link" href="innodb-storage-engine.html" title="Chapter 17 The InnoDB Storage Engine">
<code class="literal">
InnoDB
</code>
</a>
, as an
<code class="literal">
NDB
</code>
table, use the
<a class="link" href="mysql.html" title="6.5.1 mysql — The MySQL Command-Line Client">
<span class="command">
<strong>
mysql
</strong>
</span>
</a>
client to perform a
<a class="link" href="select-into.html" title="15.2.13.1 SELECT ... INTO Statement">
<code class="literal">
SELECT INTO
OUTFILE
</code>
</a>
statement to export the existing table to a
CSV file, then to execute a
<a class="link" href="create-table-like.html" title="15.1.20.3 CREATE TABLE ... LIKE Statement">
<code class="literal">
CREATE TABLE
LIKE
</code>
</a>
statement to create a new table having the same
structure as the existing table, then perform
<a class="link" href="alter-table.html" title="15.1.9 ALTER TABLE Statement">
<code class="literal">
ALTER TABLE ...
ENGINE=NDB
</code>
</a>
on the new table; after this, from the
system shell, invoke
<a class="link" href="mysql-cluster-programs-ndb-import.html" title="25.5.13 ndb_import — Import CSV Data Into NDB">
<span class="command">
<strong>
ndb_import
</strong>
</span>
</a>
to load the
data into the new
<code class="literal">
NDB
</code>
table. For example, an
existing
<code class="literal">
InnoDB
</code>
table named
<code class="literal">
myinnodb_table
</code>
in a database named
<code class="literal">
myinnodb
</code>
can be exported into an
<code class="literal">
NDB
</code>
table named
<code class="literal">
myndb_table
</code>
in a database named
<code class="literal">
myndb
</code>
as shown here, assuming that you are
already logged in as a MySQL user with the appropriate
privileges:
</p>
<div class="orderedlist">
<ol class="orderedlist" type="1">
<li class="listitem">
<p>
In the
<a class="link" href="mysql.html" title="6.5.1 mysql — The MySQL Command-Line Client">
<span class="command">
<strong>
mysql
</strong>
</span>
</a>
client:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa82000561"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">USE</span> myinnodb<span class="token punctuation">;</span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token operator">*</span> <span class="token keyword">INTO</span> <span class="token keyword">OUTFILE</span> <span class="token string">'/tmp/myndb_table.csv'</span>
<span class="token operator">></span> <span class="token keyword">FIELDS</span> <span class="token keyword">TERMINATED</span> <span class="token keyword">BY</span> <span class="token string">','</span> <span class="token keyword">OPTIONALLY</span> <span class="token keyword">ENCLOSED</span> <span class="token keyword">BY</span> <span class="token string">'"'</span> <span class="token keyword">ESCAPED</span> <span class="token keyword">BY</span> <span class="token string">'\\'</span>
<span class="token operator">></span> <span class="token keyword">LINES</span> <span class="token keyword">TERMINATED</span> <span class="token keyword">BY</span> <span class="token string">'\n'</span>
<span class="token operator">></span> <span class="token keyword">FROM</span> myinnodbtable<span class="token punctuation">;</span>
<span class="token prompt">mysql></span> <span class="token keyword">CREATE</span> <span class="token keyword">DATABASE</span> myndb<span class="token punctuation">;</span>
<span class="token prompt">mysql></span> <span class="token keyword">USE</span> myndb<span class="token punctuation">;</span>
<span class="token prompt">mysql></span> <span class="token keyword">CREATE</span> <span class="token keyword">TABLE</span> myndb_table <span class="token operator">LIKE</span> myinnodb<span class="token punctuation">.</span>myinnodb_table<span class="token punctuation">;</span>
<span class="token prompt">mysql></span> <span class="token keyword">ALTER</span> <span class="token keyword">TABLE</span> myndb_table <span class="token keyword">ENGINE</span><span class="token operator">=</span><span class="token keyword">NDB</span><span class="token punctuation">;</span>
<span class="token prompt">mysql></span> <span class="token keyword">EXIT</span><span class="token punctuation">;</span>
Bye
$<span class="token operator">></span></code></pre>
</div>
<p>
Once the target database and table have been created, a
running
<a class="link" href="mysqld.html" title="6.3.1 mysqld — The MySQL Server">
<span class="command">
<strong>
mysqld
</strong>
</span>
</a>
is no longer required. You
can stop it using
<a class="link" href="mysqladmin.html" title="6.5.2 mysqladmin — A MySQL Server Administration Program">
<span class="command">
<strong>
mysqladmin shutdown
</strong>
</span>
</a>
or
another method before proceeding, if you wish.
</p>
</li>
<li class="listitem">
<p>
In the system shell:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-terminal"><div class="docs-select-all right" id="sa59256298"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal"><span class="token comment" spellcheck="true"># if you are not already in the MySQL bin directory:</span>
<span class="token prompt">$> </span><span class="token command">cd</span> <em class="replaceable">path-to-mysql-bin-dir</em>
<span class="token prompt">$> </span><span class="token command">ndb_import</span> myndb /tmp/myndb_table<span class="token punctuation">.</span>csv <span class="token constant">--fields-optionally-enclosed-by</span>=<span class="token atrule">'"'</span> \
<span class="token constant">--fields-terminated-by</span>=<span class="token atrule">","</span> <span class="token constant">--fields-escaped-by</span>=<span class="token atrule">'\\'</span></code></pre>
</div>
<p>
The output should resemble what is shown here:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-terminal"><div class="docs-select-all right" id="sa72824657"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal">job-1 import myndb<span class="token punctuation">.</span>myndb_table from /tmp/myndb_table<span class="token punctuation">.</span>csv
job-1 <span class="token punctuation">[</span>running<span class="token punctuation">]</span> import myndb<span class="token punctuation">.</span>myndb_table from /tmp/myndb_table<span class="token punctuation">.</span>csv
job-1 <span class="token punctuation">[</span>success<span class="token punctuation">]</span> import myndb<span class="token punctuation">.</span>myndb_table from /tmp/myndb_table<span class="token punctuation">.</span>csv
job-1 imported 19984 rows in 0h0m9s at 2277 rows/s
jobs summary<span class="token punctuation">:</span> defined<span class="token punctuation">:</span> 1 run<span class="token punctuation">:</span> 1 with success<span class="token punctuation">:</span> 1 with failure<span class="token punctuation">:</span> 0
$></code></pre>
</div>
</li>
</ol>
</div>
<p>
All options that can be used with
<a class="link" href="mysql-cluster-programs-ndb-import.html" title="25.5.13 ndb_import — Import CSV Data Into NDB">
<span class="command">
<strong>
ndb_import
</strong>
</span>
</a>
are shown in the following table. Additional descriptions follow
the table.
</p>
<p>
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<a name="option_ndb_import_abort-on-error">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_abort-on-error">
<code class="option">
--abort-on-error
</code>
</a>
</p>
<a class="indexterm" name="idm46045103000368">
</a>
<a class="indexterm" name="idm46045102998880">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for abort-on-error">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--abort-on-error
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Dump core on any fatal error; used for debugging only.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_ai-increment">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_ai-increment">
<code class="option">
--ai-increment
</code>
</a>
=
<em class="replaceable">
<code>
#
</code>
</em>
</p>
<a class="indexterm" name="idm46045102988768">
</a>
<a class="indexterm" name="idm46045102987280">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for ai-increment">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--ai-increment=#
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Integer
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
1
</code>
</td>
</tr>
<tr>
<th>
Minimum Value
</th>
<td>
<code class="literal">
1
</code>
</td>
</tr>
<tr>
<th>
Maximum Value
</th>
<td>
<code class="literal">
4294967295
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
For a table with a hidden primary key, specify the
autoincrement increment, like the
<a class="link" href="replication-options-source.html#sysvar_auto_increment_increment">
<code class="literal">
auto_increment_increment
</code>
</a>
system variable does in the MySQL Server.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_ai-offset">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_ai-offset">
<code class="option">
--ai-offset
</code>
</a>
=
<em class="replaceable">
<code>
#
</code>
</em>
</p>
<a class="indexterm" name="idm46045102966336">
</a>
<a class="indexterm" name="idm46045102964848">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for ai-offset">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--ai-offset=#
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Integer
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
1
</code>
</td>
</tr>
<tr>
<th>
Minimum Value
</th>
<td>
<code class="literal">
1
</code>
</td>
</tr>
<tr>
<th>
Maximum Value
</th>
<td>
<code class="literal">
4294967295
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
For a table with hidden primary key, specify the
autoincrement offset. Similar to the
<a class="link" href="replication-options-source.html#sysvar_auto_increment_offset">
<code class="literal">
auto_increment_offset
</code>
</a>
system variable.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_ai-prefetch-sz">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_ai-prefetch-sz">
<code class="option">
--ai-prefetch-sz
</code>
</a>
=
<em class="replaceable">
<code>
#
</code>
</em>
</p>
<a class="indexterm" name="idm46045102944000">
</a>
<a class="indexterm" name="idm46045102942512">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for ai-prefetch-sz">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--ai-prefetch-sz=#
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Integer
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
1024
</code>
</td>
</tr>
<tr>
<th>
Minimum Value
</th>
<td>
<code class="literal">
1
</code>
</td>
</tr>
<tr>
<th>
Maximum Value
</th>
<td>
<code class="literal">
4294967295
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
For a table with a hidden primary key, specify the number of
autoincrement values that are prefetched. Behaves like the
<a class="link" href="mysql-cluster-options-variables.html#sysvar_ndb_autoincrement_prefetch_sz">
<code class="literal">
ndb_autoincrement_prefetch_sz
</code>
</a>
system variable does in the MySQL Server.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_character-sets-dir">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_character-sets-dir">
<code class="option">
--character-sets-dir
</code>
</a>
</p>
<a class="indexterm" name="idm46045102921952">
</a>
<a class="indexterm" name="idm46045102920496">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for character-sets-dir">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--character-sets-dir=path
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Directory containing character sets.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_connections">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_connections">
<code class="option">
--connections
</code>
</a>
=
<em class="replaceable">
<code>
#
</code>
</em>
</p>
<a class="indexterm" name="idm46045102910256">
</a>
<a class="indexterm" name="idm46045102908768">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for connections">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--connections=#
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Integer
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
1
</code>
</td>
</tr>
<tr>
<th>
Minimum Value
</th>
<td>
<code class="literal">
1
</code>
</td>
</tr>
<tr>
<th>
Maximum Value
</th>
<td>
<code class="literal">
4294967295
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Number of cluster connections to create.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_connect-retries">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_connect-retries">
<code class="option">
--connect-retries
</code>
</a>
</p>
<a class="indexterm" name="idm46045102889728">
</a>
<a class="indexterm" name="idm46045102888240">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for connect-retries">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--connect-retries=#
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Integer
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
12
</code>
</td>
</tr>
<tr>
<th>
Minimum Value
</th>
<td>
<code class="literal">
0
</code>
</td>
</tr>
<tr>
<th>
Maximum Value
</th>
<td>
<code class="literal">
12
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Number of times to retry connection before giving up.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_connect-retry-delay">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_connect-retry-delay">
<code class="option">
--connect-retry-delay
</code>
</a>
</p>
<a class="indexterm" name="idm46045102869216">
</a>
<a class="indexterm" name="idm46045102867760">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for connect-retry-delay">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--connect-retry-delay=#
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Integer
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
5
</code>
</td>
</tr>
<tr>
<th>
Minimum Value
</th>
<td>
<code class="literal">
0
</code>
</td>
</tr>
<tr>
<th>
Maximum Value
</th>
<td>
<code class="literal">
5
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Number of seconds to wait between attempts to contact
management server.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_connect-string">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_connect-string">
<code class="option">
--connect-string
</code>
</a>
</p>
<a class="indexterm" name="idm46045102848576">
</a>
<a class="indexterm" name="idm46045102847088">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for connect-string">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--connect-string=connection_string
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
String
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
[none]
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Same as
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_ndb-connectstring">
<code class="option">
--ndb-connectstring
</code>
</a>
.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_continue">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_continue">
<code class="option">
--continue
</code>
</a>
</p>
<a class="indexterm" name="idm46045102831792">
</a>
<a class="indexterm" name="idm46045102830304">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for continue">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--continue
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
When a job fails, continue to the next job.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_core-file">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_core-file">
<code class="option">
--core-file
</code>
</a>
</p>
<a class="indexterm" name="idm46045102820608">
</a>
<a class="indexterm" name="idm46045102819120">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for core-file">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--core-file
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Write core file on error; used in debugging.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_csvopt">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_csvopt">
<code class="option">
--csvopt
</code>
</a>
=
<em class="replaceable">
<code>
string
</code>
</em>
</p>
<a class="indexterm" name="idm46045102808928">
</a>
<a class="indexterm" name="idm46045102807440">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for csvopt">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--csvopt=opts
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
String
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
[none]
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Provides a shortcut method for setting typical CSV import
options. The argument to this option is a string consisting
of one or more of the following parameters:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
<code class="literal">
c
</code>
: Fields terminated by comma
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
d
</code>
: Use defaults, except where
overridden by another parameter
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
n
</code>
: Lines terminated by
<code class="literal">
\n
</code>
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
q
</code>
: Fields optionally enclosed by
double quote characters (
<code class="literal">
"
</code>
)
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
r
</code>
: Line terminated by
<code class="literal">
\r
</code>
</p>
</li>
</ul>
</div>
<p>
The order of parameters used in the argument to this option
is handled such that the rightmost parameter always takes
precedence over any potentially conflicting parameters which
have already been used in the same argument value. This also
applies to any duplicate instances of a given parameter.
</p>
<p>
This option is intended for use in testing under conditions
in which it is difficult to transmit escapes or quotation
marks.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_db-workers">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_db-workers">
<code class="option">
--db-workers
</code>
</a>
=
<em class="replaceable">
<code>
#
</code>
</em>
</p>
<a class="indexterm" name="idm46045102781504">
</a>
<a class="indexterm" name="idm46045102780016">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for db-workers">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--db-workers=#
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Integer
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
4
</code>
</td>
</tr>
<tr>
<th>
Minimum Value
</th>
<td>
<code class="literal">
1
</code>
</td>
</tr>
<tr>
<th>
Maximum Value
</th>
<td>
<code class="literal">
4294967295
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Number of threads, per data node, executing database
operations.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_defaults-file">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_defaults-file">
<code class="option">
--defaults-file
</code>
</a>
</p>
<a class="indexterm" name="idm46045102760944">
</a>
<a class="indexterm" name="idm46045102759456">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for defaults-file">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--defaults-file=path
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
String
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
[none]
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Read default options from given file only.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_defaults-extra-file">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_defaults-extra-file">
<code class="option">
--defaults-extra-file
</code>
</a>
</p>
<a class="indexterm" name="idm46045102745248">
</a>
<a class="indexterm" name="idm46045102743792">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for defaults-extra-file">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--defaults-extra-file=path
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
String
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
[none]
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Read given file after global files are read.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_defaults-group-suffix">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_defaults-group-suffix">
<code class="option">
--defaults-group-suffix
</code>
</a>
</p>
<a class="indexterm" name="idm46045102729504">
</a>
<a class="indexterm" name="idm46045102728048">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for defaults-group-suffix">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--defaults-group-suffix=string
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
String
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
[none]
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Also read groups with concat(group, suffix).
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_errins-type">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_errins-type">
<code class="option">
--errins-type
</code>
</a>
=
<em class="replaceable">
<code>
name
</code>
</em>
</p>
<a class="indexterm" name="idm46045102713344">
</a>
<a class="indexterm" name="idm46045102711856">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for errins-type">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--errins-type=name
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Enumeration
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
[none]
</code>
</td>
</tr>
<tr>
<th>
Valid Values
</th>
<td>
<p class="valid-value">
<code class="literal">
stopjob
</code>
</p>
<p class="valid-value">
<code class="literal">
stopall
</code>
</p>
<p class="valid-value">
<code class="literal">
sighup
</code>
</p>
<p class="valid-value">
<code class="literal">
sigint
</code>
</p>
<p class="valid-value">
<code class="literal">
list
</code>
</p>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Error insert type; use
<code class="literal">
list
</code>
as the
<em class="replaceable">
<code>
name
</code>
</em>
value to obtain all possible
values. This option is used for testing purposes only.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_errins-delay">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_errins-delay">
<code class="option">
--errins-delay
</code>
</a>
=
<em class="replaceable">
<code>
#
</code>
</em>
</p>
<a class="indexterm" name="idm46045102689328">
</a>
<a class="indexterm" name="idm46045102687840">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for errins-delay">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--errins-delay=#
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Integer
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
1000
</code>
</td>
</tr>
<tr>
<th>
Minimum Value
</th>
<td>
<code class="literal">
0
</code>
</td>
</tr>
<tr>
<th>
Maximum Value
</th>
<td>
<code class="literal">
4294967295
</code>
</td>
</tr>
<tr>
<th>
Unit
</th>
<td>
ms
</td>
</tr>
</tbody>
</table>
</div>
<p>
Error insert delay in milliseconds; random variation is
added. This option is used for testing purposes only.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_fields-enclosed-by">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_fields-enclosed-by">
<code class="option">
--fields-enclosed-by
</code>
</a>
=
<em class="replaceable">
<code>
char
</code>
</em>
</p>
<a class="indexterm" name="idm46045102666256">
</a>
<a class="indexterm" name="idm46045102664800">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for fields-enclosed-by">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--fields-enclosed-by=char
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
String
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
[none]
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
This works in the same way as the
<code class="literal">
FIELDS ENCLOSED
BY
</code>
option does for the
<a class="link" href="load-data.html" title="15.2.9 LOAD DATA Statement">
<code class="literal">
LOAD
DATA
</code>
</a>
statement, specifying a character to be
interpreted as quoting field values. For CSV input, this is
the same as
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_fields-optionally-enclosed-by">
<code class="option">
--fields-optionally-enclosed-by
</code>
</a>
.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_fields-escaped-by">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_fields-escaped-by">
<code class="option">
--fields-escaped-by
</code>
</a>
=
<em class="replaceable">
<code>
name
</code>
</em>
</p>
<a class="indexterm" name="idm46045102646800">
</a>
<a class="indexterm" name="idm46045102645344">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for fields-escaped-by">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--fields-escaped-by=char
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
String
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
\
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Specify an escape character in the same way as the
<code class="literal">
FIELDS ESCAPED BY
</code>
option does for the SQL
<a class="link" href="load-data.html" title="15.2.9 LOAD DATA Statement">
<code class="literal">
LOAD DATA
</code>
</a>
statement.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_fields-optionally-enclosed-by">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_fields-optionally-enclosed-by">
<code class="option">
--fields-optionally-enclosed-by
</code>
</a>
=
<em class="replaceable">
<code>
char
</code>
</em>
</p>
<a class="indexterm" name="idm46045102628704">
</a>
<a class="indexterm" name="idm46045102627200">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for fields-optionally-enclosed-by">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--fields-optionally-enclosed-by=char
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
String
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
[none]
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
This works in the same way as the
<code class="literal">
FIELDS OPTIONALLY
ENCLOSED BY
</code>
option does for the
<a class="link" href="load-data.html" title="15.2.9 LOAD DATA Statement">
<code class="literal">
LOAD DATA
</code>
</a>
statement,
specifying a character to be interpreted as optionally
quoting field values. For CSV input, this is the same as
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_fields-enclosed-by">
<code class="option">
--fields-enclosed-by
</code>
</a>
.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_fields-terminated-by">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_fields-terminated-by">
<code class="option">
--fields-terminated-by
</code>
</a>
=
<em class="replaceable">
<code>
char
</code>
</em>
</p>
<a class="indexterm" name="idm46045102609424">
</a>
<a class="indexterm" name="idm46045102607968">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for fields-terminated-by">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--fields-terminated-by=char
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
String
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
\t
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
This works in the same way as the
<code class="literal">
FIELDS TERMINATED
BY
</code>
option does for the
<a class="link" href="load-data.html" title="15.2.9 LOAD DATA Statement">
<code class="literal">
LOAD
DATA
</code>
</a>
statement, specifying a character to be
interpreted as the field separator.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_help">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_help">
<code class="option">
--help
</code>
</a>
</p>
<a class="indexterm" name="idm46045102591664">
</a>
<a class="indexterm" name="idm46045102590176">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for help">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--help
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Display help text and exit.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_idlesleep">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_idlesleep">
<code class="option">
--idlesleep
</code>
</a>
=
<em class="replaceable">
<code>
#
</code>
</em>
</p>
<a class="indexterm" name="idm46045102580000">
</a>
<a class="indexterm" name="idm46045102578512">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for idlesleep">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--idlesleep=#
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Integer
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
1
</code>
</td>
</tr>
<tr>
<th>
Minimum Value
</th>
<td>
<code class="literal">
1
</code>
</td>
</tr>
<tr>
<th>
Maximum Value
</th>
<td>
<code class="literal">
4294967295
</code>
</td>
</tr>
<tr>
<th>
Unit
</th>
<td>
ms
</td>
</tr>
</tbody>
</table>
</div>
<p>
Number of milliseconds to sleep waiting for more work to
perform.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_idlespin">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_idlespin">
<code class="option">
--idlespin
</code>
</a>
=
<em class="replaceable">
<code>
#
</code>
</em>
</p>
<a class="indexterm" name="idm46045102556976">
</a>
<a class="indexterm" name="idm46045102555488">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for idlespin">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--idlespin=#
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Integer
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
0
</code>
</td>
</tr>
<tr>
<th>
Minimum Value
</th>
<td>
<code class="literal">
0
</code>
</td>
</tr>
<tr>
<th>
Maximum Value
</th>
<td>
<code class="literal">
4294967295
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Number of times to retry before sleeping.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_ignore-lines">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_ignore-lines">
<code class="option">
--ignore-lines
</code>
</a>
=
<em class="replaceable">
<code>
#
</code>
</em>
</p>
<a class="indexterm" name="idm46045102536080">
</a>
<a class="indexterm" name="idm46045102534592">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for ignore-lines">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--ignore-lines=#
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Integer
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
0
</code>
</td>
</tr>
<tr>
<th>
Minimum Value
</th>
<td>
<code class="literal">
0
</code>
</td>
</tr>
<tr>
<th>
Maximum Value
</th>
<td>
<code class="literal">
4294967295
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Cause ndb_import to ignore the first
<em class="replaceable">
<code>
#
</code>
</em>
lines of the input file. This
can be employed to skip a file header that does not contain
any data.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_input-type">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_input-type">
<code class="option">
--input-type
</code>
</a>
=
<em class="replaceable">
<code>
name
</code>
</em>
</p>
<a class="indexterm" name="idm46045102514480">
</a>
<a class="indexterm" name="idm46045102512992">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for input-type">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--input-type=name
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Enumeration
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
csv
</code>
</td>
</tr>
<tr>
<th>
Valid Values
</th>
<td>
<p class="valid-value">
<code class="literal">
random
</code>
</p>
<p class="valid-value">
<code class="literal">
csv
</code>
</p>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Set the type of input type. The default is
<code class="literal">
csv
</code>
;
<code class="literal">
random
</code>
is
intended for testing purposes only. .
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_input-workers">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_input-workers">
<code class="option">
--input-workers
</code>
</a>
=
<em class="replaceable">
<code>
#
</code>
</em>
</p>
<a class="indexterm" name="idm46045102493216">
</a>
<a class="indexterm" name="idm46045102491728">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for input-workers">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--input-workers=#
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Integer
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
4
</code>
</td>
</tr>
<tr>
<th>
Minimum Value
</th>
<td>
<code class="literal">
1
</code>
</td>
</tr>
<tr>
<th>
Maximum Value
</th>
<td>
<code class="literal">
4294967295
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Set the number of threads processing input.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_keep-state">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_keep-state">
<code class="option">
--keep-state
</code>
</a>
</p>
<a class="indexterm" name="idm46045102472688">
</a>
<a class="indexterm" name="idm46045102471200">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for keep-state">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--keep-state
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
By default, ndb_import removes all state files (except
non-empty
<code class="filename">
*.rej
</code>
files) when it
completes a job. Specify this option (nor argument is
required) to force the program to retain all state files
instead.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_lines-terminated-by">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_lines-terminated-by">
<code class="option">
--lines-terminated-by
</code>
</a>
=
<em class="replaceable">
<code>
name
</code>
</em>
</p>
<a class="indexterm" name="idm46045102460096">
</a>
<a class="indexterm" name="idm46045102458640">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for lines-terminated-by">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--lines-terminated-by=char
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
String
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
\n
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
This works in the same way as the
<code class="literal">
LINES TERMINATED
BY
</code>
option does for the
<a class="link" href="load-data.html" title="15.2.9 LOAD DATA Statement">
<code class="literal">
LOAD
DATA
</code>
</a>
statement, specifying a character to be
interpreted as end-of-line.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_log-level">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_log-level">
<code class="option">
--log-level
</code>
</a>
=
<em class="replaceable">
<code>
#
</code>
</em>
</p>
<a class="indexterm" name="idm46045102441904">
</a>
<a class="indexterm" name="idm46045102440416">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for log-level">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--log-level=#
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Integer
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
0
</code>
</td>
</tr>
<tr>
<th>
Minimum Value
</th>
<td>
<code class="literal">
0
</code>
</td>
</tr>
<tr>
<th>
Maximum Value
</th>
<td>
<code class="literal">
2
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Performs internal logging at the given level. This option is
intended primarily for internal and development use.
</p>
<p>
In debug builds of NDB only, the logging level can be set
using this option to a maximum of 4.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_login-path">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_login-path">
<code class="option">
--login-path
</code>
</a>
</p>
<a class="indexterm" name="idm46045102420736">
</a>
<a class="indexterm" name="idm46045102419248">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for login-path">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--login-path=path
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
String
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
[none]
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Read given path from login file.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_no-login-paths">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_no-login-paths">
<code class="option">
--no-login-paths
</code>
</a>
</p>
<a class="indexterm" name="idm46045102404976">
</a>
<a class="indexterm" name="idm46045102403488">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for no-login-paths">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--no-login-paths
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Skips reading options from the login path file.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_max-rows">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_max-rows">
<code class="option">
--max-rows
</code>
</a>
=
<em class="replaceable">
<code>
#
</code>
</em>
</p>
<a class="indexterm" name="idm46045102393328">
</a>
<a class="indexterm" name="idm46045102391840">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for max-rows">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--max-rows=#
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Integer
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
0
</code>
</td>
</tr>
<tr>
<th>
Minimum Value
</th>
<td>
<code class="literal">
0
</code>
</td>
</tr>
<tr>
<th>
Maximum Value
</th>
<td>
<code class="literal">
4294967295
</code>
</td>
</tr>
<tr>
<th>
Unit
</th>
<td>
bytes
</td>
</tr>
</tbody>
</table>
</div>
<p>
Import only this number of input data rows; the default is
0, which imports all rows.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_missing-ai-column">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_missing-ai-column">
<code class="option">
--missing-ai-column
</code>
</a>
</p>
<a class="indexterm" name="idm46045102370640">
</a>
<a class="indexterm" name="idm46045102369184">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for missing-ai-column">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--missing-ai-column='name'
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Boolean
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
FALSE
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
This option can be employed when importing a single table,
or multiple tables. When used, it indicates that the CSV
file being imported does not contain any values for an
<code class="literal">
AUTO_INCREMENT
</code>
column, and that
<a class="link" href="mysql-cluster-programs-ndb-import.html" title="25.5.13 ndb_import — Import CSV Data Into NDB">
<span class="command">
<strong>
ndb_import
</strong>
</span>
</a>
should supply them; if the
option is used and the
<code class="literal">
AUTO_INCREMENT
</code>
column contains any values, the import operation cannot
proceed.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_monitor">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_monitor">
<code class="option">
--monitor
</code>
</a>
=
<em class="replaceable">
<code>
#
</code>
</em>
</p>
<a class="indexterm" name="idm46045102351376">
</a>
<a class="indexterm" name="idm46045102349888">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for monitor">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--monitor=#
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Integer
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
2
</code>
</td>
</tr>
<tr>
<th>
Minimum Value
</th>
<td>
<code class="literal">
0
</code>
</td>
</tr>
<tr>
<th>
Maximum Value
</th>
<td>
<code class="literal">
4294967295
</code>
</td>
</tr>
<tr>
<th>
Unit
</th>
<td>
bytes
</td>
</tr>
</tbody>
</table>
</div>
<p>
Periodically print the status of a running job if something
has changed (status, rejected rows, temporary errors). Set
to 0 to disable this reporting. Setting to 1 prints any
change that is seen. Higher values reduce the frequency of
this status reporting.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_ndb-connectstring">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_ndb-connectstring">
<code class="option">
--ndb-connectstring
</code>
</a>
</p>
<a class="indexterm" name="idm46045102328592">
</a>
<a class="indexterm" name="idm46045102327136">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for ndb-connectstring">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--ndb-connectstring=connection_string
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
String
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
[none]
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Set connection string for connecting to
<a class="link" href="mysql-cluster-programs-ndb-mgmd.html" title="25.5.4 ndb_mgmd — The NDB Cluster Management Server Daemon">
<span class="command">
<strong>
ndb_mgmd
</strong>
</span>
</a>
. Syntax:
<code class="literal">
[nodeid=
<em class="replaceable">
<code>
id
</code>
</em>
;][host=]
<em class="replaceable">
<code>
hostname
</code>
</em>
[:
<em class="replaceable">
<code>
port
</code>
</em>
]
</code>
.
Overrides entries in
<code class="literal">
NDB_CONNECTSTRING
</code>
and
<code class="filename">
my.cnf
</code>
.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_ndb-mgm-tls">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_ndb-mgm-tls">
<code class="option">
--ndb-mgm-tls
</code>
</a>
</p>
<a class="indexterm" name="idm46045102308096">
</a>
<a class="indexterm" name="idm46045102306608">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for ndb-mgm-tls">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--ndb-mgm-tls=level
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Enumeration
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
relaxed
</code>
</td>
</tr>
<tr>
<th>
Valid Values
</th>
<td>
<p class="valid-value">
<code class="literal">
relaxed
</code>
</p>
<p class="valid-value">
<code class="literal">
strict
</code>
</p>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Sets the level of TLS support required to connect to the
management server; one of
<code class="literal">
relaxed
</code>
or
<code class="literal">
strict
</code>
.
<code class="literal">
relaxed
</code>
(the
default) means that a TLS connection is attempted, but
success is not required;
<code class="literal">
strict
</code>
means
that TLS is required to connect.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_ndb-mgmd-host">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_ndb-mgmd-host">
<code class="option">
--ndb-mgmd-host
</code>
</a>
</p>
<a class="indexterm" name="idm46045102285552">
</a>
<a class="indexterm" name="idm46045102284064">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for ndb-mgmd-host">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--ndb-mgmd-host=connection_string
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
String
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
[none]
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Same as
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_ndb-connectstring">
<code class="option">
--ndb-connectstring
</code>
</a>
.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_ndb-nodeid">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_ndb-nodeid">
<code class="option">
--ndb-nodeid
</code>
</a>
</p>
<a class="indexterm" name="idm46045102268880">
</a>
<a class="indexterm" name="idm46045102267392">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for ndb-nodeid">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--ndb-nodeid=#
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Integer
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
[none]
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Set node ID for this node, overriding any ID set by
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_ndb-connectstring">
<code class="option">
--ndb-connectstring
</code>
</a>
.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_ndb-optimized-node-selection">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_ndb-optimized-node-selection">
<code class="option">
--ndb-optimized-node-selection
</code>
</a>
</p>
<a class="indexterm" name="idm46045102252016">
</a>
<a class="indexterm" name="idm46045102250512">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for ndb-optimized-node-selection">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--ndb-optimized-node-selection
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Enable optimizations for selection of nodes for
transactions. Enabled by default; use
<code class="option">
--skip-ndb-optimized-node-selection
</code>
to
disable.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_ndb-tls-search-path">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_ndb-tls-search-path">
<code class="option">
--ndb-tls-search-path
</code>
</a>
</p>
<a class="indexterm" name="idm46045102240160">
</a>
<a class="indexterm" name="idm46045102238704">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for ndb-tls-search-path">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--ndb-tls-search-path=list
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Path name
</td>
</tr>
<tr>
<th>
Default Value (Unix)
</th>
<td>
<code class="literal">
$HOME/ndb-tls
</code>
</td>
</tr>
<tr>
<th>
Default Value (Windows)
</th>
<td>
<code class="literal">
$HOMEDIR/ndb-tls
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Specify a list of directories to search for a CA file. On
Unix platforms, the directory names are separated by colons
(
<code class="literal">
:
</code>
); on Windows systems, the semicolon
character (
<code class="literal">
;
</code>
) is used as the separator. A
directory reference may be relative or absolute; it may
contain one or more environment variables, each denoted by a
prefixed dollar sign (
<code class="literal">
$
</code>
), and expanded
prior to use.
</p>
<p>
Searching begins with the leftmost named directory and
proceeds from left to right until a file is found. An empty
string denotes an empty search path, which causes all
searches to fail. A string consisting of a single dot
(
<code class="literal">
.
</code>
) indicates that the search path
limited to the current working directory.
</p>
<p>
If no search path is supplied, the compiled-in default value
is used. This value depends on the platform used: On
Windows, this is
<code class="literal">
\ndb-tls
</code>
; on other
platforms (including Linux), it is
<code class="literal">
$HOME/ndb-tls
</code>
. This can be overridden by
compiling NDB Cluster using
<a class="link" href="source-configuration-options.html#option_cmake_with_ndb_tls_search_path">
<code class="option">
-DWITH_NDB_TLS_SEARCH_PATH
</code>
</a>
.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_no-asynch">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_no-asynch">
<code class="option">
--no-asynch
</code>
</a>
</p>
<a class="indexterm" name="idm46045102214944">
</a>
<a class="indexterm" name="idm46045102213456">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for no-asynch">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--no-asynch
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Run database operations as batches, in single transactions.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_no-defaults">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_no-defaults">
<code class="option">
--no-defaults
</code>
</a>
</p>
<a class="indexterm" name="idm46045102203728">
</a>
<a class="indexterm" name="idm46045102202240">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for no-defaults">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--no-defaults
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Do not read default options from any option file other than
login file.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_no-hint">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_no-hint">
<code class="option">
--no-hint
</code>
</a>
</p>
<a class="indexterm" name="idm46045102192416">
</a>
<a class="indexterm" name="idm46045102190928">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for no-hint">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--no-hint
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Do not use distribution key hinting to select a data node.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_opbatch">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_opbatch">
<code class="option">
--opbatch
</code>
</a>
=
<em class="replaceable">
<code>
#
</code>
</em>
</p>
<a class="indexterm" name="idm46045102180832">
</a>
<a class="indexterm" name="idm46045102179344">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for opbatch">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--opbatch=#
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Integer
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
256
</code>
</td>
</tr>
<tr>
<th>
Minimum Value
</th>
<td>
<code class="literal">
1
</code>
</td>
</tr>
<tr>
<th>
Maximum Value
</th>
<td>
<code class="literal">
4294967295
</code>
</td>
</tr>
<tr>
<th>
Unit
</th>
<td>
bytes
</td>
</tr>
</tbody>
</table>
</div>
<p>
Set a limit on the number of operations (including blob
operations), and thus the number of asynchronous
transactions, per execution batch.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_opbytes">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_opbytes">
<code class="option">
--opbytes
</code>
</a>
=
<em class="replaceable">
<code>
#
</code>
</em>
</p>
<a class="indexterm" name="idm46045102157632">
</a>
<a class="indexterm" name="idm46045102156144">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for opbytes">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--opbytes=#
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Integer
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
0
</code>
</td>
</tr>
<tr>
<th>
Minimum Value
</th>
<td>
<code class="literal">
0
</code>
</td>
</tr>
<tr>
<th>
Maximum Value
</th>
<td>
<code class="literal">
4294967295
</code>
</td>
</tr>
<tr>
<th>
Unit
</th>
<td>
bytes
</td>
</tr>
</tbody>
</table>
</div>
<p>
Set a limit on the number of bytes per execution batch. Use
0 for no limit.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_output-type">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_output-type">
<code class="option">
--output-type
</code>
</a>
=
<em class="replaceable">
<code>
name
</code>
</em>
</p>
<a class="indexterm" name="idm46045102134608">
</a>
<a class="indexterm" name="idm46045102133120">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for output-type">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--output-type=name
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Enumeration
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
ndb
</code>
</td>
</tr>
<tr>
<th>
Valid Values
</th>
<td>
<code class="literal">
null
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Set the output type.
<code class="literal">
ndb
</code>
is the default.
<code class="literal">
null
</code>
is used only for testing.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_output-workers">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_output-workers">
<code class="option">
--output-workers
</code>
</a>
=
<em class="replaceable">
<code>
#
</code>
</em>
</p>
<a class="indexterm" name="idm46045102114640">
</a>
<a class="indexterm" name="idm46045102113152">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for output-workers">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--output-workers=#
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Integer
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
2
</code>
</td>
</tr>
<tr>
<th>
Minimum Value
</th>
<td>
<code class="literal">
1
</code>
</td>
</tr>
<tr>
<th>
Maximum Value
</th>
<td>
<code class="literal">
4294967295
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Set the number of threads processing output or relaying
database operations.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_pagesize">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_pagesize">
<code class="option">
--pagesize
</code>
</a>
=
<em class="replaceable">
<code>
#
</code>
</em>
</p>
<a class="indexterm" name="idm46045102093552">
</a>
<a class="indexterm" name="idm46045102092064">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for pagesize">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--pagesize=#
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Integer
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
4096
</code>
</td>
</tr>
<tr>
<th>
Minimum Value
</th>
<td>
<code class="literal">
1
</code>
</td>
</tr>
<tr>
<th>
Maximum Value
</th>
<td>
<code class="literal">
4294967295
</code>
</td>
</tr>
<tr>
<th>
Unit
</th>
<td>
bytes
</td>
</tr>
</tbody>
</table>
</div>
<p>
Align I/O buffers to the given size.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_pagecnt">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_pagecnt">
<code class="option">
--pagecnt
</code>
</a>
=
<em class="replaceable">
<code>
#
</code>
</em>
</p>
<a class="indexterm" name="idm46045102070512">
</a>
<a class="indexterm" name="idm46045102069024">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for pagecnt">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--pagecnt=#
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Integer
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
64
</code>
</td>
</tr>
<tr>
<th>
Minimum Value
</th>
<td>
<code class="literal">
1
</code>
</td>
</tr>
<tr>
<th>
Maximum Value
</th>
<td>
<code class="literal">
4294967295
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Set the size of I/O buffers as multiple of page size. The
CSV input worker allocates buffer that is doubled in size.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_polltimeout">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_polltimeout">
<code class="option">
--polltimeout
</code>
</a>
=
<em class="replaceable">
<code>
#
</code>
</em>
</p>
<a class="indexterm" name="idm46045102049520">
</a>
<a class="indexterm" name="idm46045102048032">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for polltimeout">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--polltimeout=#
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Integer
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
1000
</code>
</td>
</tr>
<tr>
<th>
Minimum Value
</th>
<td>
<code class="literal">
1
</code>
</td>
</tr>
<tr>
<th>
Maximum Value
</th>
<td>
<code class="literal">
4294967295
</code>
</td>
</tr>
<tr>
<th>
Unit
</th>
<td>
ms
</td>
</tr>
</tbody>
</table>
</div>
<p>
Set a timeout per poll for completed asynchronous
transactions; polling continues until all polls are
completed, or until an error occurs.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_print-defaults">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_print-defaults">
<code class="option">
--print-defaults
</code>
</a>
</p>
<a class="indexterm" name="idm46045102026816">
</a>
<a class="indexterm" name="idm46045102025328">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for print-defaults">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--print-defaults
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Print program argument list and exit.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_rejects">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_rejects">
<code class="option">
--rejects
</code>
</a>
=
<em class="replaceable">
<code>
#
</code>
</em>
</p>
<a class="indexterm" name="idm46045102015104">
</a>
<a class="indexterm" name="idm46045102013616">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for rejects">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--rejects=#
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Integer
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
0
</code>
</td>
</tr>
<tr>
<th>
Minimum Value
</th>
<td>
<code class="literal">
0
</code>
</td>
</tr>
<tr>
<th>
Maximum Value
</th>
<td>
<code class="literal">
4294967295
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Limit the number of rejected rows (rows with permanent
errors) in the data load. The default is 0, which means that
any rejected row causes a fatal error. Any rows causing the
limit to be exceeded are added to the
<code class="filename">
.rej
</code>
file.
</p>
<p>
The limit imposed by this option is effective for the
duration of the current run. A run restarted using
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_resume">
<code class="option">
--resume
</code>
</a>
is considered a
<span class="quote">
“
<span class="quote">
new
</span>
”
</span>
run for this purpose.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_resume">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_resume">
<code class="option">
--resume
</code>
</a>
</p>
<a class="indexterm" name="idm46045101991616">
</a>
<a class="indexterm" name="idm46045101990128">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for resume">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--resume
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
If a job is aborted (due to a temporary db error or when
interrupted by the user), resume with any rows not yet
processed.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_rowbatch">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_rowbatch">
<code class="option">
--rowbatch
</code>
</a>
=
<em class="replaceable">
<code>
#
</code>
</em>
</p>
<a class="indexterm" name="idm46045101979872">
</a>
<a class="indexterm" name="idm46045101978384">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for rowbatch">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--rowbatch=#
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Integer
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
0
</code>
</td>
</tr>
<tr>
<th>
Minimum Value
</th>
<td>
<code class="literal">
0
</code>
</td>
</tr>
<tr>
<th>
Maximum Value
</th>
<td>
<code class="literal">
4294967295
</code>
</td>
</tr>
<tr>
<th>
Unit
</th>
<td>
rows
</td>
</tr>
</tbody>
</table>
</div>
<p>
Set a limit on the number of rows per row queue. Use 0 for
no limit.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_rowbytes">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_rowbytes">
<code class="option">
--rowbytes
</code>
</a>
=
<em class="replaceable">
<code>
#
</code>
</em>
</p>
<a class="indexterm" name="idm46045101956816">
</a>
<a class="indexterm" name="idm46045101955328">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for rowbytes">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--rowbytes=#
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Integer
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
262144
</code>
</td>
</tr>
<tr>
<th>
Minimum Value
</th>
<td>
<code class="literal">
0
</code>
</td>
</tr>
<tr>
<th>
Maximum Value
</th>
<td>
<code class="literal">
4294967295
</code>
</td>
</tr>
<tr>
<th>
Unit
</th>
<td>
bytes
</td>
</tr>
</tbody>
</table>
</div>
<p>
Set a limit on the number of bytes per row queue. Use 0 for
no limit.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_stats">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_stats">
<code class="option">
--stats
</code>
</a>
</p>
<a class="indexterm" name="idm46045101934224">
</a>
<a class="indexterm" name="idm46045101932736">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for stats">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--stats
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Save information about options related to performance and
other internal statistics in files named
<code class="filename">
*.sto
</code>
and
<code class="filename">
*.stt
</code>
.
These files are always kept on successful completion (even
if
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_keep-state">
<code class="option">
--keep-state
</code>
</a>
is not
also specified).
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_state-dir">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_state-dir">
<code class="option">
--state-dir
</code>
</a>
=
<em class="replaceable">
<code>
name
</code>
</em>
</p>
<a class="indexterm" name="idm46045101919952">
</a>
<a class="indexterm" name="idm46045101918464">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for state-dir">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--state-dir=path
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
String
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
.
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Where to write the state files
(
<code class="filename">
<em class="replaceable">
<code>
tbl_name
</code>
</em>
.map
</code>
,
<code class="filename">
<em class="replaceable">
<code>
tbl_name
</code>
</em>
.rej
</code>
,
<code class="filename">
<em class="replaceable">
<code>
tbl_name
</code>
</em>
.res
</code>
,
and
<code class="filename">
<em class="replaceable">
<code>
tbl_name
</code>
</em>
.stt
</code>
)
produced by a run of the program; the default is the current
directory.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_table">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_table">
<code class="option">
--table=
<em class="replaceable">
<code>
name
</code>
</em>
</code>
</a>
</p>
<a class="indexterm" name="idm46045101899968">
</a>
<a class="indexterm" name="idm46045101898480">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for table">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--table=name
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
String
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
[input file base name]
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
By default,
<a class="link" href="mysql-cluster-programs-ndb-import.html" title="25.5.13 ndb_import — Import CSV Data Into NDB">
<span class="command">
<strong>
ndb_import
</strong>
</span>
</a>
attempts to import
data into a table whose name is the base name of the CSV
file from which the data is being read. You can override the
choice of table name by specifying it with the
<code class="option">
--table
</code>
option (short form
<code class="option">
-t
</code>
).
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_tempdelay">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_tempdelay">
<code class="option">
--tempdelay
</code>
</a>
=
<em class="replaceable">
<code>
#
</code>
</em>
</p>
<a class="indexterm" name="idm46045101881456">
</a>
<a class="indexterm" name="idm46045101879968">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for tempdelay">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--tempdelay=#
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Integer
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
10
</code>
</td>
</tr>
<tr>
<th>
Minimum Value
</th>
<td>
<code class="literal">
0
</code>
</td>
</tr>
<tr>
<th>
Maximum Value
</th>
<td>
<code class="literal">
4294967295
</code>
</td>
</tr>
<tr>
<th>
Unit
</th>
<td>
ms
</td>
</tr>
</tbody>
</table>
</div>
<p>
Number of milliseconds to sleep between temporary errors.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_temperrors">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_temperrors">
<code class="option">
--temperrors
</code>
</a>
=
<em class="replaceable">
<code>
#
</code>
</em>
</p>
<a class="indexterm" name="idm46045101858448">
</a>
<a class="indexterm" name="idm46045101856960">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for temperrors">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--temperrors=#
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Integer
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
0
</code>
</td>
</tr>
<tr>
<th>
Minimum Value
</th>
<td>
<code class="literal">
0
</code>
</td>
</tr>
<tr>
<th>
Maximum Value
</th>
<td>
<code class="literal">
4294967295
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Number of times a transaction can fail due to a temporary
error, per execution batch. The default is 0, which means
that any temporary error is fatal. Temporary errors do not
cause any rows to be added to the
<code class="filename">
.rej
</code>
file.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_verbose">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_verbose">
<code class="option">
--verbose
</code>
</a>
,
<code class="option">
-v
</code>
</p>
<a class="indexterm" name="idm46045101836512">
</a>
<a class="indexterm" name="idm46045101835024">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for verbose">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--verbose[=#]
</code>
</td>
</tr>
<tr>
<th>
Type
</th>
<td>
Boolean
</td>
</tr>
<tr>
<th>
Default Value
</th>
<td>
<code class="literal">
false
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Enable verbose output.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_usage">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_usage">
<code class="option">
--usage
</code>
</a>
</p>
<a class="indexterm" name="idm46045101820944">
</a>
<a class="indexterm" name="idm46045101819456">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for usage">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--usage
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Display help text and exit; same as
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_help">
<code class="option">
--help
</code>
</a>
.
</p>
</li>
<li class="listitem">
<p>
<a name="option_ndb_import_version">
</a>
<a class="link" href="mysql-cluster-programs-ndb-import.html#option_ndb_import_version">
<code class="option">
--version
</code>
</a>
</p>
<a class="indexterm" name="idm46045101808688">
</a>
<a class="indexterm" name="idm46045101807200">
</a>
<div class="informaltable">
<table frame="box" rules="all" summary="Properties for version">
<colgroup>
<col style="width: 30%"/>
<col style="width: 70%"/>
</colgroup>
<tbody>
<tr>
<th>
Command-Line Format
</th>
<td>
<code class="literal">
--version
</code>
</td>
</tr>
</tbody>
</table>
</div>
<p>
Display version information and exit.
</p>
</li>
</ul>
</div>
<p>
As with
<a class="link" href="load-data.html" title="15.2.9 LOAD DATA Statement">
<code class="literal">
LOAD DATA
</code>
</a>
, options for
field and line formatting much match those used to create the
CSV file, whether this was done using
<a class="link" href="select-into.html" title="15.2.13.1 SELECT ... INTO Statement">
<code class="literal">
SELECT INTO ...
OUTFILE
</code>
</a>
, or by some other means. There is no
equivalent to the
<a class="link" href="load-data.html" title="15.2.9 LOAD DATA Statement">
<code class="literal">
LOAD DATA
</code>
</a>
statement
<code class="literal">
STARTING WITH
</code>
option.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/assigning-passwords.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="assigning-passwords">
</a>
8.2.14 Assigning Account Passwords
</h3>
</div>
</div>
</div>
<a class="indexterm" name="idm46045248743216">
</a>
<a class="indexterm" name="idm46045248742176">
</a>
<a class="indexterm" name="idm46045248741104">
</a>
<a class="indexterm" name="idm46045248739616">
</a>
<p>
Required credentials for clients that connect to the MySQL server
can include a password. This section describes how to assign
passwords for MySQL accounts.
</p>
<p>
MySQL stores credentials in the
<code class="literal">
user
</code>
table in
the
<code class="literal">
mysql
</code>
system database. Operations that
assign or modify passwords are permitted only to users with the
<a class="link" href="privileges-provided.html#priv_create-user">
<code class="literal">
CREATE USER
</code>
</a>
privilege, or,
alternatively, privileges for the
<code class="literal">
mysql
</code>
database (
<a class="link" href="privileges-provided.html#priv_insert">
<code class="literal">
INSERT
</code>
</a>
privilege to
create new accounts,
<a class="link" href="privileges-provided.html#priv_update">
<code class="literal">
UPDATE
</code>
</a>
privilege to modify existing accounts). If the
<a class="link" href="server-system-variables.html#sysvar_read_only">
<code class="literal">
read_only
</code>
</a>
system variable is
enabled, use of account-modification statements such as
<a class="link" href="create-user.html" title="15.7.1.3 CREATE USER Statement">
<code class="literal">
CREATE USER
</code>
</a>
or
<a class="link" href="alter-user.html" title="15.7.1.1 ALTER USER Statement">
<code class="literal">
ALTER USER
</code>
</a>
additionally requires
the
<a class="link" href="privileges-provided.html#priv_connection-admin">
<code class="literal">
CONNECTION_ADMIN
</code>
</a>
privilege (or
the deprecated
<a class="link" href="privileges-provided.html#priv_super">
<code class="literal">
SUPER
</code>
</a>
privilege).
</p>
<p>
The discussion here summarizes syntax only for the most common
password-assignment statements. For complete details on other
possibilities, see
<a class="xref" href="create-user.html" title="15.7.1.3 CREATE USER Statement">
Section 15.7.1.3, “CREATE USER Statement”
</a>
,
<a class="xref" href="alter-user.html" title="15.7.1.1 ALTER USER Statement">
Section 15.7.1.1, “ALTER USER Statement”
</a>
, and
<a class="xref" href="set-password.html" title="15.7.1.10 SET PASSWORD Statement">
Section 15.7.1.10, “SET PASSWORD Statement”
</a>
.
</p>
<p>
MySQL uses plugins to perform client authentication; see
<a class="xref" href="pluggable-authentication.html" title="8.2.17 Pluggable Authentication">
Section 8.2.17, “Pluggable Authentication”
</a>
. In password-assigning
statements, the authentication plugin associated with an account
performs any hashing required of a cleartext password specified.
This enables MySQL to obfuscate passwords prior to storing them in
the
<code class="literal">
mysql.user
</code>
system table. For the statements
described here, MySQL automatically hashes the password specified.
There are also syntax for
<a class="link" href="create-user.html" title="15.7.1.3 CREATE USER Statement">
<code class="literal">
CREATE
USER
</code>
</a>
and
<a class="link" href="alter-user.html" title="15.7.1.1 ALTER USER Statement">
<code class="literal">
ALTER USER
</code>
</a>
that
permits hashed values to be specified literally. For details, see
the descriptions of those statements.
</p>
<p>
To assign a password when you create a new account, use
<a class="link" href="create-user.html" title="15.7.1.3 CREATE USER Statement">
<code class="literal">
CREATE USER
</code>
</a>
and include an
<code class="literal">
IDENTIFIED BY
</code>
clause:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-sql"><div class="docs-select-all right" id="sa78048932"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">CREATE</span> <span class="token keyword">USER</span> <span class="token string">'jeffrey'</span>@<span class="token string">'localhost'</span> <span class="token keyword">IDENTIFIED</span> <span class="token keyword">BY</span> <span class="token string">'<em class="replaceable">password</em>'</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
<a class="link" href="create-user.html" title="15.7.1.3 CREATE USER Statement">
<code class="literal">
CREATE USER
</code>
</a>
also supports syntax
for specifying the account authentication plugin. See
<a class="xref" href="create-user.html" title="15.7.1.3 CREATE USER Statement">
Section 15.7.1.3, “CREATE USER Statement”
</a>
.
</p>
<p>
To assign or change a password for an existing account, use the
<a class="link" href="alter-user.html" title="15.7.1.1 ALTER USER Statement">
<code class="literal">
ALTER USER
</code>
</a>
statement with an
<code class="literal">
IDENTIFIED BY
</code>
clause:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-sql"><div class="docs-select-all right" id="sa30278216"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">ALTER</span> <span class="token keyword">USER</span> <span class="token string">'jeffrey'</span>@<span class="token string">'localhost'</span> <span class="token keyword">IDENTIFIED</span> <span class="token keyword">BY</span> <span class="token string">'<em class="replaceable">password</em>'</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
If you are not connected as an anonymous user, you can change your
own password without naming your own account literally:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-sql"><div class="docs-select-all right" id="sa6909271"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">ALTER</span> <span class="token keyword">USER</span> <span class="token function">USER</span><span class="token punctuation">(</span><span class="token punctuation">)</span> <span class="token keyword">IDENTIFIED</span> <span class="token keyword">BY</span> <span class="token string">'<em class="replaceable">password</em>'</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
To change an account password from the command line, use the
<a class="link" href="mysqladmin.html" title="6.5.2 mysqladmin — A MySQL Server Administration Program">
<span class="command">
<strong>
mysqladmin
</strong>
</span>
</a>
command:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-terminal"><div class="docs-select-all right" id="sa27971734"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal">mysqladmin <span class="token property">-u</span> <em class="replaceable">user_name</em> <span class="token property">-h</span> <em class="replaceable">host_name</em> password <span class="token atrule">"<em class="replaceable">password</em>"</span></code></pre>
</div>
<p>
The account for which this command sets the password is the one
with a row in the
<code class="literal">
mysql.user
</code>
system table that
matches
<em class="replaceable">
<code>
user_name
</code>
</em>
in the
<code class="literal">
User
</code>
column and the client host
<span class="emphasis">
<em>
from
which you connect
</em>
</span>
in the
<code class="literal">
Host
</code>
column.
</p>
<div class="warning" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Warning
</div>
<p>
Setting a password using
<a class="link" href="mysqladmin.html" title="6.5.2 mysqladmin — A MySQL Server Administration Program">
<span class="command">
<strong>
mysqladmin
</strong>
</span>
</a>
should be
considered
<span class="emphasis">
<em>
insecure
</em>
</span>
. On some systems, your
password becomes visible to system status programs such as
<span class="command">
<strong>
ps
</strong>
</span>
that may be invoked by other users to
display command lines. MySQL clients typically overwrite the
command-line password argument with zeros during their
initialization sequence. However, there is still a brief
interval during which the value is visible. Also, on some
systems this overwriting strategy is ineffective and the
password remains visible to
<span class="command">
<strong>
ps
</strong>
</span>
. (SystemV Unix
systems and perhaps others are subject to this problem.)
</p>
</div>
<p>
If you are using MySQL Replication, be aware that a password used
by a replica as part of
<a class="link" href="change-replication-source-to.html" title="15.4.2.2 CHANGE REPLICATION SOURCE TO Statement">
<code class="literal">
CHANGE REPLICATION
SOURCE TO
</code>
</a>
is effectively limited to 32 characters in
length; if the password is longer, any excess characters are
truncated. This is not due to any limit imposed by MySQL Server
generally, but rather is an issue specific to MySQL Replication.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/charset-compatibility.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="charset-compatibility">
</a>
12.3.10 Compatibility with Other DBMSs
</h3>
</div>
</div>
</div>
<p>
For MaxDB compatibility these two statements are the same:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa73700236"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">CREATE</span> <span class="token keyword">TABLE</span> t1 <span class="token punctuation">(</span>f1 <span class="token datatype">CHAR</span><span class="token punctuation">(</span><em class="replaceable">N</em><span class="token punctuation">)</span> <span class="token keyword">UNICODE</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token keyword">CREATE</span> <span class="token keyword">TABLE</span> t1 <span class="token punctuation">(</span>f1 <span class="token datatype">CHAR</span><span class="token punctuation">(</span><em class="replaceable">N</em><span class="token punctuation">)</span> <span class="token keyword">CHARACTER</span> <span class="token keyword">SET</span> ucs2<span class="token punctuation">)</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
Both the
<code class="literal">
UNICODE
</code>
attribute and the
<code class="literal">
ucs2
</code>
character set are deprecated; you should
expect them to be removed in a future version of MySQL.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/sys-schema-table-lock-waits.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="sys-schema-table-lock-waits">
</a>
30.4.3.28 The schema_table_lock_waits and x$schema_table_lock_waits Views
</h4>
</div>
</div>
</div>
<a class="indexterm" name="idm46045062455408">
</a>
<a class="indexterm" name="idm46045062453952">
</a>
<a class="indexterm" name="idm46045062452448">
</a>
<a class="indexterm" name="idm46045062450944">
</a>
<p>
These views display which sessions are blocked waiting on
metadata locks, and what is blocking them.
</p>
<p>
The column descriptions here are brief. For additional
information, see the description of the Performance Schema
<a class="link" href="performance-schema-metadata-locks-table.html" title="29.12.13.3 The metadata_locks Table">
<code class="literal">
metadata_locks
</code>
</a>
table at
<a class="xref" href="performance-schema-metadata-locks-table.html" title="29.12.13.3 The metadata_locks Table">
Section 29.12.13.3, “The metadata_locks Table”
</a>
.
</p>
<p>
The
<a class="link" href="sys-schema-table-lock-waits.html" title="30.4.3.28 The schema_table_lock_waits and x$schema_table_lock_waits Views">
<code class="literal">
schema_table_lock_waits
</code>
</a>
and
<a class="link" href="sys-schema-table-lock-waits.html" title="30.4.3.28 The schema_table_lock_waits and x$schema_table_lock_waits Views">
<code class="literal">
x$schema_table_lock_waits
</code>
</a>
views
have these columns:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<code class="literal">
object_schema
</code>
</p>
<p>
The schema containing the object to be locked.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
object_name
</code>
</p>
<p>
The name of the instrumented object.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
waiting_thread_id
</code>
</p>
<p>
The thread ID of the thread that is waiting for the lock.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
waiting_pid
</code>
</p>
<p>
The processlist ID of the thread that is waiting for the
lock.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
waiting_account
</code>
</p>
<p>
The account associated with the session that is waiting
for the lock.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
waiting_lock_type
</code>
</p>
<p>
The type of the waiting lock.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
waiting_lock_duration
</code>
</p>
<p>
How long the waiting lock has been waiting.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
waiting_query
</code>
</p>
<p>
The statement that is waiting for the lock.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
waiting_query_secs
</code>
</p>
<p>
How long the statement has been waiting, in seconds.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
waiting_query_rows_affected
</code>
</p>
<p>
The number of rows affected by the statement.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
waiting_query_rows_examined
</code>
</p>
<p>
The number of rows read from storage engines by the
statement.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
blocking_thread_id
</code>
</p>
<p>
The thread ID of the thread that is blocking the waiting
lock.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
blocking_pid
</code>
</p>
<p>
The processlist ID of the thread that is blocking the
waiting lock.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
blocking_account
</code>
</p>
<p>
The account associated with the thread that is blocking
the waiting lock.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
blocking_lock_type
</code>
</p>
<p>
The type of lock that is blocking the waiting lock.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
blocking_lock_duration
</code>
</p>
<p>
How long the blocking lock has been held.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
sql_kill_blocking_query
</code>
</p>
<p>
The
<a class="link" href="kill.html" title="15.7.8.4 KILL Statement">
<code class="literal">
KILL
</code>
</a>
statement to
execute to kill the blocking statement.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
sql_kill_blocking_connection
</code>
</p>
<p>
The
<a class="link" href="kill.html" title="15.7.8.4 KILL Statement">
<code class="literal">
KILL
</code>
</a>
statement to
execute to kill the session running the blocking
statement.
</p>
</li>
</ul>
</div>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/selinux-checking.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="selinux-checking">
</a>
8.7.1 Check if SELinux is Enabled
</h3>
</div>
</div>
</div>
<a class="indexterm" name="idm46045231644080">
</a>
<p>
SELinux is enabled by default on some Linux distributions
including Oracle Linux, RHEL, CentOS, and Fedora. Use the
<span class="command">
<strong>
sestatus
</strong>
</span>
command to determine if SELinux is
enabled on your distribution:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-terminal"><div class="docs-select-all right" id="sa65472562"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-terminal"><span class="token prompt">$> </span><span class="token command">sestatus</span>
SELinux status<span class="token punctuation">:</span> enabled
SELinuxfs mount<span class="token punctuation">:</span> /sys/fs/selinux
SELinux root directory<span class="token punctuation">:</span> /etc/selinux
Loaded policy name<span class="token punctuation">:</span> targeted
Current mode<span class="token punctuation">:</span> enforcing
Mode from config file<span class="token punctuation">:</span> enforcing
Policy MLS status<span class="token punctuation">:</span> enabled
Policy deny_unknown status<span class="token punctuation">:</span> allowed
Memory protection checking<span class="token punctuation">:</span> actual <span class="token punctuation">(</span>secure<span class="token punctuation">)</span>
Max kernel policy version<span class="token punctuation">:</span> 31</code></pre>
</div>
<p>
If SELinux is disabled or the
<span class="command">
<strong>
sestatus
</strong>
</span>
command
is not found, refer to your distribution's SELinux documentation
for guidance before enabling SELinux.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-ndbinfo-dictionary-columns.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="mysql-cluster-ndbinfo-dictionary-columns">
</a>
25.6.17.23 The ndbinfo dictionary_columns Table
</h4>
</div>
</div>
</div>
<a class="indexterm" name="idm46045089819600">
</a>
<p>
The table provides
<code class="literal">
NDB
</code>
dictionary information
about columns of
<code class="literal">
NDB
</code>
tables.
<code class="literal">
dictionary_columns
</code>
has the columns listed
here (with brief descriptions):
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<code class="literal">
table_id
</code>
</p>
<p>
ID of the table containing the column
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
column_id
</code>
</p>
<p>
The column's unique ID
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
name
</code>
</p>
<p>
Name of the column
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
column_type
</code>
</p>
<p>
Data type of the column from the NDB API; see
<a class="ulink" href="/doc/ndbapi/en/ndb-column.html#ndb-column-type" target="_top">
Column::Type
</a>
, for possible values
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
default_value
</code>
</p>
<p>
The column's default value, if any
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
nullable
</code>
</p>
<p>
Either of
<code class="literal">
NULL
</code>
or
<code class="literal">
NOT
NULL
</code>
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
array_type
</code>
</p>
<p>
The column's internal attribute storage format; one of
<code class="literal">
FIXED
</code>
,
<code class="literal">
SHORT_VAR
</code>
, or
<code class="literal">
MEDIUM_VAR
</code>
; for more information, see
<a class="ulink" href="/doc/ndbapi/en/ndb-column.html#ndb-column-arraytype" target="_top">
Column::ArrayType
</a>
, in the NDB API
documentation
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
storage_type
</code>
</p>
<p>
Type of storage used by the table; either of
<code class="literal">
MEMORY
</code>
or
<code class="literal">
DISK
</code>
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
primary_key
</code>
</p>
<p>
<code class="literal">
1
</code>
if this is a primary key column,
otherwise
<code class="literal">
0
</code>
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
partition_key
</code>
</p>
<p>
<code class="literal">
1
</code>
if this is a partitioning key column,
otherwise
<code class="literal">
0
</code>
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
dynamic
</code>
</p>
<p>
<code class="literal">
1
</code>
if the column is dynamic, otherwise
<code class="literal">
0
</code>
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
auto_inc
</code>
</p>
<p>
<code class="literal">
1
</code>
if this is an
<code class="literal">
AUTO_INCREMENT
</code>
column, otherwise
<code class="literal">
0
</code>
</p>
</li>
</ul>
</div>
<p>
You can obtain information about all of the columns in a given
table by joining
<code class="literal">
dictionary_columns
</code>
with the
<a class="link" href="mysql-cluster-ndbinfo-dictionary-tables.html" title="25.6.17.24 The ndbinfo dictionary_tables Table">
<code class="literal">
dictionary_tables
</code>
</a>
table, like
this:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa6188904"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">SELECT</span> dc<span class="token punctuation">.</span><span class="token operator">*</span>
<span class="token keyword">FROM</span> dictionary_columns dc
<span class="token keyword">JOIN</span> dictionary_tables dt
<span class="token keyword">ON</span> dc<span class="token punctuation">.</span>table_id<span class="token operator">=</span>dt<span class="token punctuation">.</span>table_id
<span class="token keyword">WHERE</span> dt<span class="token punctuation">.</span><span class="token keyword">table_name</span><span class="token operator">=</span><span class="token string">'t1'</span>
<span class="token operator">AND</span> dt<span class="token punctuation">.</span>database_name<span class="token operator">=</span><span class="token string">'mydb'</span><span class="token punctuation">;</span></code></pre>
</div>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Note
</div>
<p>
Blob columns are not shown in this table. This is a known
issue.
</p>
</div>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-host-cache-table.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="performance-schema-host-cache-table">
</a>
29.12.22.3 The host_cache Table
</h4>
</div>
</div>
</div>
<a class="indexterm" name="idm46045067598896">
</a>
<a class="indexterm" name="idm46045067597408">
</a>
<p>
The MySQL server maintains an in-memory host cache that
contains client host name and IP address information and is
used to avoid Domain Name System (DNS) lookups. The
<a class="link" href="performance-schema-host-cache-table.html" title="29.12.22.3 The host_cache Table">
<code class="literal">
host_cache
</code>
</a>
table exposes the
contents of this cache. The
<a class="link" href="server-system-variables.html#sysvar_host_cache_size">
<code class="literal">
host_cache_size
</code>
</a>
system
variable controls the size of the host cache, as well as the
size of the
<a class="link" href="performance-schema-host-cache-table.html" title="29.12.22.3 The host_cache Table">
<code class="literal">
host_cache
</code>
</a>
table. For
operational and configuration information about the host
cache, see
<a class="xref" href="host-cache.html" title="7.1.12.3 DNS Lookups and the Host Cache">
Section 7.1.12.3, “DNS Lookups and the Host Cache”
</a>
.
</p>
<p>
Because the
<a class="link" href="performance-schema-host-cache-table.html" title="29.12.22.3 The host_cache Table">
<code class="literal">
host_cache
</code>
</a>
table
exposes the contents of the host cache, it can be examined
using
<a class="link" href="select.html" title="15.2.13 SELECT Statement">
<code class="literal">
SELECT
</code>
</a>
statements. This
may help you diagnose the causes of connection problems.
</p>
<p>
The
<a class="link" href="performance-schema-host-cache-table.html" title="29.12.22.3 The host_cache Table">
<code class="literal">
host_cache
</code>
</a>
table has these
columns:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<code class="literal">
IP
</code>
</p>
<p>
The IP address of the client that connected to the server,
expressed as a string.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
HOST
</code>
</p>
<p>
The resolved DNS host name for that client IP, or
<code class="literal">
NULL
</code>
if the name is unknown.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
HOST_VALIDATED
</code>
</p>
<p>
Whether the IP-to-host name-to-IP DNS resolution was
performed successfully for the client IP. If
<code class="literal">
HOST_VALIDATED
</code>
is
<code class="literal">
YES
</code>
, the
<code class="literal">
HOST
</code>
column
is used as the host name corresponding to the IP so that
additional calls to DNS can be avoided. While
<code class="literal">
HOST_VALIDATED
</code>
is
<code class="literal">
NO
</code>
, DNS resolution is attempted for
each connection attempt, until it eventually completes
with either a valid result or a permanent error. This
information enables the server to avoid caching bad or
missing host names during temporary DNS failures, which
would negatively affect clients forever.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
SUM_CONNECT_ERRORS
</code>
</p>
<p>
The number of connection errors that are deemed
<span class="quote">
“
<span class="quote">
blocking
</span>
”
</span>
(assessed against the
<a class="link" href="server-system-variables.html#sysvar_max_connect_errors">
<code class="literal">
max_connect_errors
</code>
</a>
system
variable). Only protocol handshake errors are counted, and
only for hosts that passed validation
(
<code class="literal">
HOST_VALIDATED = YES
</code>
).
</p>
<p>
Once
<code class="literal">
SUM_CONNECT_ERRORS
</code>
for a given
host reaches the value of
<a class="link" href="server-system-variables.html#sysvar_max_connect_errors">
<code class="literal">
max_connect_errors
</code>
</a>
, new
connections from that host are blocked. The
<code class="literal">
SUM_CONNECT_ERRORS
</code>
value can exceed the
<a class="link" href="server-system-variables.html#sysvar_max_connect_errors">
<code class="literal">
max_connect_errors
</code>
</a>
value
because multiple connection attempts from a host can occur
simultaneously while the host is not blocked. Any or all
of them can fail, independently incrementing
<code class="literal">
SUM_CONNECT_ERRORS
</code>
, possibly beyond the
value of
<a class="link" href="server-system-variables.html#sysvar_max_connect_errors">
<code class="literal">
max_connect_errors
</code>
</a>
.
</p>
<p>
Suppose that
<a class="link" href="server-system-variables.html#sysvar_max_connect_errors">
<code class="literal">
max_connect_errors
</code>
</a>
is 200
and
<code class="literal">
SUM_CONNECT_ERRORS
</code>
for a given host
is 199. If 10 clients attempt to connect from that host
simultaneously, none of them are blocked because
<code class="literal">
SUM_CONNECT_ERRORS
</code>
has not reached 200.
If blocking errors occur for five of the clients,
<code class="literal">
SUM_CONNECT_ERRORS
</code>
is increased by one
for each client, for a resulting
<code class="literal">
SUM_CONNECT_ERRORS
</code>
value of 204. The
other five clients succeed and are not blocked because the
value of
<code class="literal">
SUM_CONNECT_ERRORS
</code>
when their
connection attempts began had not reached 200. New
connections from the host that begin after
<code class="literal">
SUM_CONNECT_ERRORS
</code>
reaches 200 are
blocked.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
COUNT_HOST_BLOCKED_ERRORS
</code>
</p>
<p>
The number of connections that were blocked because
<code class="literal">
SUM_CONNECT_ERRORS
</code>
exceeded the value
of the
<a class="link" href="server-system-variables.html#sysvar_max_connect_errors">
<code class="literal">
max_connect_errors
</code>
</a>
system variable.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
COUNT_NAMEINFO_TRANSIENT_ERRORS
</code>
</p>
<p>
The number of transient errors during IP-to-host name DNS
resolution.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
COUNT_NAMEINFO_PERMANENT_ERRORS
</code>
</p>
<p>
The number of permanent errors during IP-to-host name DNS
resolution.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
COUNT_FORMAT_ERRORS
</code>
</p>
<p>
The number of host name format errors. MySQL does not
perform matching of
<code class="literal">
Host
</code>
column values
in the
<code class="literal">
mysql.user
</code>
system table against
host names for which one or more of the initial components
of the name are entirely numeric, such as
<code class="literal">
1.2.example.com
</code>
. The client IP address
is used instead. For the rationale why this type of
matching does not occur, see
<a class="xref" href="account-names.html" title="8.2.4 Specifying Account Names">
Section 8.2.4, “Specifying Account Names”
</a>
.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
COUNT_ADDRINFO_TRANSIENT_ERRORS
</code>
</p>
<p>
The number of transient errors during host name-to-IP
reverse DNS resolution.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
COUNT_ADDRINFO_PERMANENT_ERRORS
</code>
</p>
<p>
The number of permanent errors during host name-to-IP
reverse DNS resolution.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
COUNT_FCRDNS_ERRORS
</code>
</p>
<p>
The number of forward-confirmed reverse DNS errors. These
errors occur when IP-to-host name-to-IP DNS resolution
produces an IP address that does not match the client
originating IP address.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
COUNT_HOST_ACL_ERRORS
</code>
</p>
<p>
The number of errors that occur because no users are
permitted to connect from the client host. In such cases,
the server returns
<a class="ulink" href="/doc/mysql-errors/8.4/en/server-error-reference.html#error_er_host_not_privileged" target="_top">
<code class="literal">
ER_HOST_NOT_PRIVILEGED
</code>
</a>
and
does not even ask for a user name or password.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
COUNT_NO_AUTH_PLUGIN_ERRORS
</code>
</p>
<p>
The number of errors due to requests for an unavailable
authentication plugin. A plugin can be unavailable if, for
example, it was never loaded or a load attempt failed.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
COUNT_AUTH_PLUGIN_ERRORS
</code>
</p>
<p>
The number of errors reported by authentication plugins.
</p>
<p>
An authentication plugin can report different error codes
to indicate the root cause of a failure. Depending on the
type of error, one of these columns is incremented:
<code class="literal">
COUNT_AUTHENTICATION_ERRORS
</code>
,
<code class="literal">
COUNT_AUTH_PLUGIN_ERRORS
</code>
,
<code class="literal">
COUNT_HANDSHAKE_ERRORS
</code>
. New return
codes are an optional extension to the existing plugin
API. Unknown or unexpected plugin errors are counted in
the
<code class="literal">
COUNT_AUTH_PLUGIN_ERRORS
</code>
column.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
COUNT_HANDSHAKE_ERRORS
</code>
</p>
<p>
The number of errors detected at the wire protocol level.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
COUNT_PROXY_USER_ERRORS
</code>
</p>
<p>
The number of errors detected when proxy user A is proxied
to another user B who does not exist.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
COUNT_PROXY_USER_ACL_ERRORS
</code>
</p>
<p>
The number of errors detected when proxy user A is proxied
to another user B who does exist but for whom A does not
have the
<a class="link" href="privileges-provided.html#priv_proxy">
<code class="literal">
PROXY
</code>
</a>
privilege.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
COUNT_AUTHENTICATION_ERRORS
</code>
</p>
<p>
The number of errors caused by failed authentication.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
COUNT_SSL_ERRORS
</code>
</p>
<p>
The number of errors due to SSL problems.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
COUNT_MAX_USER_CONNECTIONS_ERRORS
</code>
</p>
<p>
The number of errors caused by exceeding per-user
connection quotas. See
<a class="xref" href="user-resources.html" title="8.2.21 Setting Account Resource Limits">
Section 8.2.21, “Setting Account Resource Limits”
</a>
.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
COUNT_MAX_USER_CONNECTIONS_PER_HOUR_ERRORS
</code>
</p>
<p>
The number of errors caused by exceeding per-user
connections-per-hour quotas. See
<a class="xref" href="user-resources.html" title="8.2.21 Setting Account Resource Limits">
Section 8.2.21, “Setting Account Resource Limits”
</a>
.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
COUNT_DEFAULT_DATABASE_ERRORS
</code>
</p>
<p>
The number of errors related to the default database. For
example, the database does not exist or the user has no
privileges to access it.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
COUNT_INIT_CONNECT_ERRORS
</code>
</p>
<p>
The number of errors caused by execution failures of
statements in the
<a class="link" href="server-system-variables.html#sysvar_init_connect">
<code class="literal">
init_connect
</code>
</a>
system
variable value.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
COUNT_LOCAL_ERRORS
</code>
</p>
<p>
The number of errors local to the server implementation
and not related to the network, authentication, or
authorization. For example, out-of-memory conditions fall
into this category.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
COUNT_UNKNOWN_ERRORS
</code>
</p>
<p>
The number of other, unknown errors not accounted for by
other columns in this table. This column is reserved for
future use, in case new error conditions must be reported,
and if preserving the backward compatibility and structure
of the
<a class="link" href="performance-schema-host-cache-table.html" title="29.12.22.3 The host_cache Table">
<code class="literal">
host_cache
</code>
</a>
table is
required.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
FIRST_SEEN
</code>
</p>
<p>
The timestamp of the first connection attempt seen from
the client in the
<code class="literal">
IP
</code>
column.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
LAST_SEEN
</code>
</p>
<p>
The timestamp of the most recent connection attempt seen
from the client in the
<code class="literal">
IP
</code>
column.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
FIRST_ERROR_SEEN
</code>
</p>
<p>
The timestamp of the first error seen from the client in
the
<code class="literal">
IP
</code>
column.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
LAST_ERROR_SEEN
</code>
</p>
<p>
The timestamp of the most recent error seen from the
client in the
<code class="literal">
IP
</code>
column.
</p>
</li>
</ul>
</div>
<p>
The
<a class="link" href="performance-schema-host-cache-table.html" title="29.12.22.3 The host_cache Table">
<code class="literal">
host_cache
</code>
</a>
table has these
indexes:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
Primary key on (
<code class="literal">
IP
</code>
)
</p>
</li>
<li class="listitem">
<p>
Index on (
<code class="literal">
HOST
</code>
)
</p>
</li>
</ul>
</div>
<p>
<a class="link" href="truncate-table.html" title="15.1.37 TRUNCATE TABLE Statement">
<code class="literal">
TRUNCATE TABLE
</code>
</a>
is permitted for
the
<a class="link" href="performance-schema-host-cache-table.html" title="29.12.22.3 The host_cache Table">
<code class="literal">
host_cache
</code>
</a>
table. It requires
the
<a class="link" href="privileges-provided.html#priv_drop">
<code class="literal">
DROP
</code>
</a>
privilege for the
table. Truncating the table flushes the host cache, which has
the effects described in
<a class="xref" href="host-cache.html#host-cache-flushing" title="Flushing the Host Cache">
Flushing the Host Cache
</a>
.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/show-create-function.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="show-create-function">
</a>
15.7.7.9 SHOW CREATE FUNCTION Statement
</h4>
</div>
</div>
</div>
<a class="indexterm" name="idm46045170917888">
</a>
<div class="copytoclipboard-wrapper">
<pre class="programlisting one-line language-sql"><div class="docs-select-all right" id="sa21868352"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">SHOW</span> <span class="token keyword">CREATE</span> <span class="token keyword">FUNCTION</span> <em class="replaceable">func_name</em></code></pre>
</div>
<p>
This statement is similar to
<a class="link" href="show-create-procedure.html" title="15.7.7.10 SHOW CREATE PROCEDURE Statement">
<code class="literal">
SHOW CREATE
PROCEDURE
</code>
</a>
but for stored functions. See
<a class="xref" href="show-create-procedure.html" title="15.7.7.10 SHOW CREATE PROCEDURE Statement">
Section 15.7.7.10, “SHOW CREATE PROCEDURE Statement”
</a>
.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/information-schema-triggers-table.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="information-schema-triggers-table">
</a>
28.3.44 The INFORMATION_SCHEMA TRIGGERS Table
</h3>
</div>
</div>
</div>
<a class="indexterm" name="idm46045078178480">
</a>
<p>
The
<a class="link" href="information-schema-triggers-table.html" title="28.3.44 The INFORMATION_SCHEMA TRIGGERS Table">
<code class="literal">
TRIGGERS
</code>
</a>
table provides
information about triggers. To see information about a table's
triggers, you must have the
<a class="link" href="privileges-provided.html#priv_trigger">
<code class="literal">
TRIGGER
</code>
</a>
privilege for the table.
</p>
<p>
The
<a class="link" href="information-schema-triggers-table.html" title="28.3.44 The INFORMATION_SCHEMA TRIGGERS Table">
<code class="literal">
TRIGGERS
</code>
</a>
table has these columns:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<code class="literal">
TRIGGER_CATALOG
</code>
</p>
<p>
The name of the catalog to which the trigger belongs. This
value is always
<code class="literal">
def
</code>
.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
TRIGGER_SCHEMA
</code>
</p>
<p>
The name of the schema (database) to which the trigger
belongs.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
TRIGGER_NAME
</code>
</p>
<p>
The name of the trigger.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
EVENT_MANIPULATION
</code>
</p>
<p>
The trigger event. This is the type of operation on the
associated table for which the trigger activates. The value is
<code class="literal">
INSERT
</code>
(a row was inserted),
<code class="literal">
DELETE
</code>
(a row was deleted), or
<code class="literal">
UPDATE
</code>
(a row was modified).
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
EVENT_OBJECT_CATALOG
</code>
,
<code class="literal">
EVENT_OBJECT_SCHEMA
</code>
, and
<code class="literal">
EVENT_OBJECT_TABLE
</code>
</p>
<p>
As noted in
<a class="xref" href="triggers.html" title="27.3 Using Triggers">
Section 27.3, “Using Triggers”
</a>
, every trigger is
associated with exactly one table. These columns indicate the
catalog and schema (database) in which this table occurs, and
the table name, respectively. The
<code class="literal">
EVENT_OBJECT_CATALOG
</code>
value is always
<code class="literal">
def
</code>
.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
ACTION_ORDER
</code>
</p>
<p>
The ordinal position of the trigger's action within the list
of triggers on the same table with the same
<code class="literal">
EVENT_MANIPULATION
</code>
and
<code class="literal">
ACTION_TIMING
</code>
values.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
ACTION_CONDITION
</code>
</p>
<p>
This value is always
<code class="literal">
NULL
</code>
.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
ACTION_STATEMENT
</code>
</p>
<p>
The trigger body; that is, the statement executed when the
trigger activates. This text uses UTF-8 encoding.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
ACTION_ORIENTATION
</code>
</p>
<p>
This value is always
<code class="literal">
ROW
</code>
.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
ACTION_TIMING
</code>
</p>
<p>
Whether the trigger activates before or after the triggering
event. The value is
<code class="literal">
BEFORE
</code>
or
<code class="literal">
AFTER
</code>
.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
ACTION_REFERENCE_OLD_TABLE
</code>
</p>
<p>
This value is always
<code class="literal">
NULL
</code>
.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
ACTION_REFERENCE_NEW_TABLE
</code>
</p>
<p>
This value is always
<code class="literal">
NULL
</code>
.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
ACTION_REFERENCE_OLD_ROW
</code>
and
<code class="literal">
ACTION_REFERENCE_NEW_ROW
</code>
</p>
<p>
The old and new column identifiers, respectively. The
<code class="literal">
ACTION_REFERENCE_OLD_ROW
</code>
value is always
<code class="literal">
OLD
</code>
and the
<code class="literal">
ACTION_REFERENCE_NEW_ROW
</code>
value is always
<code class="literal">
NEW
</code>
.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
CREATED
</code>
</p>
<p>
The date and time when the trigger was created. This is a
<code class="literal">
TIMESTAMP(2)
</code>
value (with a fractional part
in hundredths of seconds) for triggers.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
SQL_MODE
</code>
</p>
<p>
The SQL mode in effect when the trigger was created, and under
which the trigger executes. For the permitted values, see
<a class="xref" href="sql-mode.html" title="7.1.11 Server SQL Modes">
Section 7.1.11, “Server SQL Modes”
</a>
.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
DEFINER
</code>
</p>
<p>
The account named in the
<code class="literal">
DEFINER
</code>
clause
(often the user who created the trigger), in
<code class="literal">
'
<em class="replaceable">
<code>
user_name
</code>
</em>
'@'
<em class="replaceable">
<code>
host_name
</code>
</em>
'
</code>
format.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
CHARACTER_SET_CLIENT
</code>
</p>
<p>
The session value of the
<a class="link" href="server-system-variables.html#sysvar_character_set_client">
<code class="literal">
character_set_client
</code>
</a>
system
variable when the trigger was created.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
COLLATION_CONNECTION
</code>
</p>
<p>
The session value of the
<a class="link" href="server-system-variables.html#sysvar_collation_connection">
<code class="literal">
collation_connection
</code>
</a>
system
variable when the trigger was created.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
DATABASE_COLLATION
</code>
</p>
<p>
The collation of the database with which the trigger is
associated.
</p>
</li>
</ul>
</div>
<h4>
<a name="idm46045078112656">
</a>
Example
</h4>
<p>
The following example uses the
<code class="literal">
ins_sum
</code>
trigger
defined in
<a class="xref" href="triggers.html" title="27.3 Using Triggers">
Section 27.3, “Using Triggers”
</a>
:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa30941126"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token operator">*</span> <span class="token keyword">FROM</span> INFORMATION_SCHEMA<span class="token punctuation">.</span><span class="token keyword">TRIGGERS</span>
<span class="token keyword">WHERE</span> TRIGGER_SCHEMA<span class="token operator">=</span><span class="token string">'test'</span> <span class="token operator">AND</span> TRIGGER_NAME<span class="token operator">=</span><span class="token string">'ins_sum'</span>\G
<span class="token output"><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span> 1. row <span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span>
TRIGGER_CATALOG<span class="token punctuation">:</span> def
TRIGGER_SCHEMA<span class="token punctuation">:</span> test
TRIGGER_NAME<span class="token punctuation">:</span> ins_sum
EVENT_MANIPULATION<span class="token punctuation">:</span> INSERT
EVENT_OBJECT_CATALOG<span class="token punctuation">:</span> def
EVENT_OBJECT_SCHEMA<span class="token punctuation">:</span> test
EVENT_OBJECT_TABLE<span class="token punctuation">:</span> account
ACTION_ORDER<span class="token punctuation">:</span> 1
ACTION_CONDITION<span class="token punctuation">:</span> NULL
ACTION_STATEMENT<span class="token punctuation">:</span> SET @sum = @sum + NEW.amount
ACTION_ORIENTATION<span class="token punctuation">:</span> ROW
ACTION_TIMING<span class="token punctuation">:</span> BEFORE
ACTION_REFERENCE_OLD_TABLE<span class="token punctuation">:</span> NULL
ACTION_REFERENCE_NEW_TABLE<span class="token punctuation">:</span> NULL
ACTION_REFERENCE_OLD_ROW<span class="token punctuation">:</span> OLD
ACTION_REFERENCE_NEW_ROW<span class="token punctuation">:</span> NEW
CREATED<span class="token punctuation">:</span> 2018-08-08 10<span class="token punctuation">:</span>10<span class="token punctuation">:</span>12.61
SQL_MODE<span class="token punctuation">:</span> ONLY_FULL_GROUP_BY,STRICT_TRANS_TABLES,
NO_ZERO_IN_DATE,NO_ZERO_DATE,
ERROR_FOR_DIVISION_BY_ZERO,
NO_ENGINE_SUBSTITUTION
DEFINER<span class="token punctuation">:</span> me@localhost
CHARACTER_SET_CLIENT<span class="token punctuation">:</span> utf8mb4
COLLATION_CONNECTION<span class="token punctuation">:</span> utf8mb4_0900_ai_ci
DATABASE_COLLATION<span class="token punctuation">:</span> utf8mb4_0900_ai_ci</span></code></pre>
</div>
<p>
Trigger information is also available from the
<a class="link" href="show-triggers.html" title="15.7.7.40 SHOW TRIGGERS Statement">
<code class="literal">
SHOW TRIGGERS
</code>
</a>
statement. See
<a class="xref" href="show-triggers.html" title="15.7.7.40 SHOW TRIGGERS Statement">
Section 15.7.7.40, “SHOW TRIGGERS Statement”
</a>
.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-ndbinfo-server-transactions.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="mysql-cluster-ndbinfo-server-transactions">
</a>
25.6.17.56 The ndbinfo server_transactions Table
</h4>
</div>
</div>
</div>
<a class="indexterm" name="idm46045087849552">
</a>
<p>
The
<code class="literal">
server_transactions
</code>
table is subset of
the
<a class="link" href="mysql-cluster-ndbinfo-cluster-transactions.html" title="25.6.17.9 The ndbinfo cluster_transactions Table">
<code class="literal">
cluster_transactions
</code>
</a>
table, but includes only those transactions in which the current
SQL node (MySQL Server) is a participant, while including the
relevant connection IDs.
</p>
<p>
The
<code class="literal">
server_transactions
</code>
table contains the
following columns:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<code class="literal">
mysql_connection_id
</code>
</p>
<p>
MySQL Server connection ID
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
node_id
</code>
</p>
<p>
Transaction coordinator node ID
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
block_instance
</code>
</p>
<p>
Transaction coordinator block instance
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
transid
</code>
</p>
<p>
Transaction ID
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
state
</code>
</p>
<p>
Operation state (see text for possible values)
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
count_operations
</code>
</p>
<p>
Number of stateful operations in the transaction
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
outstanding_operations
</code>
</p>
<p>
Operations still being executed by local data management
layer (LQH blocks)
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
inactive_seconds
</code>
</p>
<p>
Time spent waiting for API
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
client_node_id
</code>
</p>
<p>
Client node ID
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
client_block_ref
</code>
</p>
<p>
Client block reference
</p>
</li>
</ul>
</div>
<h5>
<a name="idm46045087824832">
</a>
Notes
</h5>
<p>
The
<code class="literal">
mysql_connection_id
</code>
is the same as the
connection or session ID shown in the output of
<a class="link" href="show-processlist.html" title="15.7.7.31 SHOW PROCESSLIST Statement">
<code class="literal">
SHOW PROCESSLIST
</code>
</a>
. It is obtained
from the
<code class="literal">
INFORMATION_SCHEMA
</code>
table
<a class="link" href="information-schema-ndb-transid-mysql-connection-map-table.html" title="28.3.18 The INFORMATION_SCHEMA ndb_transid_mysql_connection_map Table">
<code class="literal">
NDB_TRANSID_MYSQL_CONNECTION_MAP
</code>
</a>
.
</p>
<p>
<code class="literal">
block_instance
</code>
refers to an instance of a
kernel block. Together with the block name, this number can be
used to look up a given instance in the
<a class="link" href="mysql-cluster-ndbinfo-threadblocks.html" title="25.6.17.62 The ndbinfo threadblocks Table">
<code class="literal">
threadblocks
</code>
</a>
table.
</p>
<p>
The transaction ID (
<code class="literal">
transid
</code>
) is a unique
64-bit number which can be obtained using the NDB API's
<a class="ulink" href="/doc/ndbapi/en/ndb-ndbtransaction.html#ndb-ndbtransaction-gettransactionid" target="_top">
<code class="literal">
getTransactionId()
</code>
</a>
method. (Currently, the MySQL Server does not expose the NDB API
transaction ID of an ongoing transaction.)
</p>
<p>
The
<code class="literal">
state
</code>
column can have any one of the
values
<code class="literal">
CS_ABORTING
</code>
,
<code class="literal">
CS_COMMITTING
</code>
,
<code class="literal">
CS_COMMIT_SENT
</code>
,
<code class="literal">
CS_COMPLETE_SENT
</code>
,
<code class="literal">
CS_COMPLETING
</code>
,
<code class="literal">
CS_CONNECTED
</code>
,
<code class="literal">
CS_DISCONNECTED
</code>
,
<code class="literal">
CS_FAIL_ABORTED
</code>
,
<code class="literal">
CS_FAIL_ABORTING
</code>
,
<code class="literal">
CS_FAIL_COMMITTED
</code>
,
<code class="literal">
CS_FAIL_COMMITTING
</code>
,
<code class="literal">
CS_FAIL_COMPLETED
</code>
,
<code class="literal">
CS_FAIL_PREPARED
</code>
,
<code class="literal">
CS_PREPARE_TO_COMMIT
</code>
,
<code class="literal">
CS_RECEIVING
</code>
,
<code class="literal">
CS_REC_COMMITTING
</code>
,
<code class="literal">
CS_RESTART
</code>
,
<code class="literal">
CS_SEND_FIRE_TRIG_REQ
</code>
,
<code class="literal">
CS_STARTED
</code>
,
<code class="literal">
CS_START_COMMITTING
</code>
,
<code class="literal">
CS_START_SCAN
</code>
,
<code class="literal">
CS_WAIT_ABORT_CONF
</code>
,
<code class="literal">
CS_WAIT_COMMIT_CONF
</code>
,
<code class="literal">
CS_WAIT_COMPLETE_CONF
</code>
,
<code class="literal">
CS_WAIT_FIRE_TRIG_REQ
</code>
. (If the MySQL Server
is running with
<a class="link" href="mysql-cluster-options-variables.html#sysvar_ndbinfo_show_hidden">
<code class="literal">
ndbinfo_show_hidden
</code>
</a>
enabled,
you can view this list of states by selecting from the
<code class="literal">
ndb$dbtc_apiconnect_state
</code>
table, which is
normally hidden.)
</p>
<p>
In
<code class="literal">
client_node_id
</code>
and
<code class="literal">
client_block_ref
</code>
,
<code class="literal">
client
</code>
refers to an NDB Cluster API or SQL node (that is, an NDB API
client or a MySQL Server attached to the cluster).
</p>
<p>
The
<code class="literal">
block_instance
</code>
column provides the
<a class="ulink" href="/doc/ndb-internals/en/ndb-internals-kernel-blocks-dbtc.html" target="_top">
<code class="literal">
DBTC
</code>
</a>
kernel block instance
number. You can use this to obtain information about specific
threads from the
<a class="link" href="mysql-cluster-ndbinfo-threadblocks.html" title="25.6.17.62 The ndbinfo threadblocks Table">
<code class="literal">
threadblocks
</code>
</a>
table.
</p>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/slow-query-log.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="slow-query-log">
</a>
7.4.5 The Slow Query Log
</h3>
</div>
</div>
</div>
<a class="indexterm" name="idm46045257590816">
</a>
<a class="indexterm" name="idm46045257589744">
</a>
<p>
The slow query log consists of SQL statements that take more than
<a class="link" href="server-system-variables.html#sysvar_long_query_time">
<code class="literal">
long_query_time
</code>
</a>
seconds to
execute and require at least
<a class="link" href="server-system-variables.html#sysvar_min_examined_row_limit">
<code class="literal">
min_examined_row_limit
</code>
</a>
rows to be
examined. The slow query log can be used to find queries that take
a long time to execute and are therefore candidates for
optimization. However, examining a long slow query log can be a
time-consuming task. To make this easier, you can use the
<a class="link" href="mysqldumpslow.html" title="6.6.10 mysqldumpslow — Summarize Slow Query Log Files">
<span class="command">
<strong>
mysqldumpslow
</strong>
</span>
</a>
command to process a slow query
log file and summarize its contents. See
<a class="xref" href="mysqldumpslow.html" title="6.6.10 mysqldumpslow — Summarize Slow Query Log Files">
Section 6.6.10, “mysqldumpslow — Summarize Slow Query Log Files”
</a>
.
</p>
<p>
The time to acquire the initial locks is not counted as execution
time.
<a class="link" href="mysqld.html" title="6.3.1 mysqld — The MySQL Server">
<span class="command">
<strong>
mysqld
</strong>
</span>
</a>
writes a statement to the slow
query log after it has been executed and after all locks have been
released, so log order might differ from execution order.
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<a class="xref" href="slow-query-log.html#slow-query-log-parameters" title="Slow Query Log Parameters">
Slow Query Log Parameters
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="xref" href="slow-query-log.html#slow-query-log-contents" title="Slow Query Log Contents">
Slow Query Log Contents
</a>
</p>
</li>
</ul>
</div>
<div class="simplesect">
<div class="titlepage">
<div>
<div class="simple">
<h4 class="title">
<a name="slow-query-log-parameters">
</a>
Slow Query Log Parameters
</h4>
</div>
</div>
</div>
<p>
The minimum and default values of
<a class="link" href="server-system-variables.html#sysvar_long_query_time">
<code class="literal">
long_query_time
</code>
</a>
are 0 and 10,
respectively. The value can be specified to a resolution of
microseconds.
</p>
<p>
By default, administrative statements are not logged, nor are
queries that do not use indexes for lookups. This behavior can
be changed using
<a class="link" href="server-system-variables.html#sysvar_log_slow_admin_statements">
<code class="literal">
log_slow_admin_statements
</code>
</a>
and
<a class="link" href="server-system-variables.html#sysvar_log_queries_not_using_indexes">
<code class="literal">
log_queries_not_using_indexes
</code>
</a>
,
as described later.
</p>
<p>
By default, the slow query log is disabled. To specify the
initial slow query log state explicitly, use
<a class="link" href="server-system-variables.html#sysvar_slow_query_log">
<code class="option">
--slow_query_log[={0|1}]
</code>
</a>
. With no
argument or an argument of 1,
<a class="link" href="server-system-variables.html#sysvar_slow_query_log">
<code class="option">
--slow_query_log
</code>
</a>
enables the log.
With an argument of 0, this option disables the log. To specify
a log file name, use
<a class="link" href="server-system-variables.html#sysvar_slow_query_log_file">
<code class="option">
--slow_query_log_file=
<em class="replaceable">
<code>
file_name
</code>
</em>
</code>
</a>
.
To specify the log destination, use the
<a class="link" href="server-system-variables.html#sysvar_log_output">
<code class="literal">
log_output
</code>
</a>
system variable (as
described in
<a class="xref" href="log-destinations.html" title="7.4.1 Selecting General Query Log and Slow Query Log Output Destinations">
Section 7.4.1, “Selecting General Query Log and Slow Query Log Output Destinations”
</a>
).
</p>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<div class="admon-title">
Note
</div>
<p>
If you specify the
<code class="literal">
TABLE
</code>
log destination,
see
<a class="xref" href="log-destinations.html#log-destinations-tables-open-files" title="Log Tables and “Too many open files” Errors">
Log Tables and
<span class="quote">
“
<span class="quote">
Too many open files
</span>
”
</span>
Errors
</a>
.
</p>
</div>
<p>
If you specify no name for the slow query log file, the default
name is
<code class="filename">
<em class="replaceable">
<code>
host_name
</code>
</em>
-slow.log
</code>
.
The server creates the file in the data directory unless an
absolute path name is given to specify a different directory.
</p>
<p>
To disable or enable the slow query log or change the log file
name at runtime, use the global
<a class="link" href="server-system-variables.html#sysvar_slow_query_log">
<code class="literal">
slow_query_log
</code>
</a>
and
<a class="link" href="server-system-variables.html#sysvar_slow_query_log_file">
<code class="literal">
slow_query_log_file
</code>
</a>
system
variables. Set
<a class="link" href="server-system-variables.html#sysvar_slow_query_log">
<code class="literal">
slow_query_log
</code>
</a>
to 0 to disable the log or to 1 to enable it. Set
<a class="link" href="server-system-variables.html#sysvar_slow_query_log_file">
<code class="literal">
slow_query_log_file
</code>
</a>
to specify
the name of the log file. If a log file already is open, it is
closed and the new file is opened.
</p>
<p>
The server writes less information to the slow query log if you
use the
<a class="link" href="server-options.html#option_mysqld_log-short-format">
<code class="option">
--log-short-format
</code>
</a>
option.
</p>
<p>
To include slow administrative statements in the slow query log,
enable the
<a class="link" href="server-system-variables.html#sysvar_log_slow_admin_statements">
<code class="literal">
log_slow_admin_statements
</code>
</a>
system variable. Administrative statements include
<a class="link" href="alter-table.html" title="15.1.9 ALTER TABLE Statement">
<code class="literal">
ALTER TABLE
</code>
</a>
,
<a class="link" href="analyze-table.html" title="15.7.3.1 ANALYZE TABLE Statement">
<code class="literal">
ANALYZE TABLE
</code>
</a>
,
<a class="link" href="check-table.html" title="15.7.3.2 CHECK TABLE Statement">
<code class="literal">
CHECK TABLE
</code>
</a>
,
<a class="link" href="create-index.html" title="15.1.15 CREATE INDEX Statement">
<code class="literal">
CREATE INDEX
</code>
</a>
,
<a class="link" href="drop-index.html" title="15.1.27 DROP INDEX Statement">
<code class="literal">
DROP INDEX
</code>
</a>
,
<a class="link" href="optimize-table.html" title="15.7.3.4 OPTIMIZE TABLE Statement">
<code class="literal">
OPTIMIZE TABLE
</code>
</a>
, and
<a class="link" href="repair-table.html" title="15.7.3.5 REPAIR TABLE Statement">
<code class="literal">
REPAIR TABLE
</code>
</a>
.
</p>
<p>
To include queries that do not use indexes for row lookups in
the statements written to the slow query log, enable the
<a class="link" href="server-system-variables.html#sysvar_log_queries_not_using_indexes">
<code class="literal">
log_queries_not_using_indexes
</code>
</a>
system variable. (Even with that variable enabled, the server
does not log queries that would not benefit from the presence of
an index due to the table having fewer than two rows.)
</p>
<p>
When queries that do not use an index are logged, the slow query
log may grow quickly. It is possible to put a rate limit on
these queries by setting the
<a class="link" href="server-system-variables.html#sysvar_log_throttle_queries_not_using_indexes">
<code class="literal">
log_throttle_queries_not_using_indexes
</code>
</a>
system variable. By default, this variable is 0, which means
there is no limit. Positive values impose a per-minute limit on
logging of queries that do not use indexes. The first such query
opens a 60-second window within which the server logs queries up
to the given limit, then suppresses additional queries. If there
are suppressed queries when the window ends, the server logs a
summary that indicates how many there were and the aggregate
time spent in them. The next 60-second window begins when the
server logs the next query that does not use indexes.
</p>
<p>
The server uses the controlling parameters in the following
order to determine whether to write a query to the slow query
log:
</p>
<div class="orderedlist">
<ol class="orderedlist" type="1">
<li class="listitem">
<p>
The query must either not be an administrative statement, or
<a class="link" href="server-system-variables.html#sysvar_log_slow_admin_statements">
<code class="literal">
log_slow_admin_statements
</code>
</a>
must be enabled.
</p>
</li>
<li class="listitem">
<p>
The query must have taken at least
<a class="link" href="server-system-variables.html#sysvar_long_query_time">
<code class="literal">
long_query_time
</code>
</a>
seconds, or
<a class="link" href="server-system-variables.html#sysvar_log_queries_not_using_indexes">
<code class="literal">
log_queries_not_using_indexes
</code>
</a>
must be enabled and the query used no indexes for row
lookups.
</p>
</li>
<li class="listitem">
<p>
The query must have examined at least
<a class="link" href="server-system-variables.html#sysvar_min_examined_row_limit">
<code class="literal">
min_examined_row_limit
</code>
</a>
rows.
</p>
</li>
<li class="listitem">
<p>
The query must not be suppressed according to the
<a class="link" href="server-system-variables.html#sysvar_log_throttle_queries_not_using_indexes">
<code class="literal">
log_throttle_queries_not_using_indexes
</code>
</a>
setting.
</p>
</li>
</ol>
</div>
<p>
The
<a class="link" href="server-system-variables.html#sysvar_log_timestamps">
<code class="literal">
log_timestamps
</code>
</a>
system
variable controls the time zone of timestamps in messages
written to the slow query log file (as well as to the general
query log file and the error log). It does not affect the time
zone of general query log and slow query log messages written to
log tables, but rows retrieved from those tables can be
converted from the local system time zone to any desired time
zone with
<a class="link" href="date-and-time-functions.html#function_convert-tz">
<code class="literal">
CONVERT_TZ()
</code>
</a>
or by
setting the session
<a class="link" href="server-system-variables.html#sysvar_time_zone">
<code class="literal">
time_zone
</code>
</a>
system variable.
</p>
<p>
By default, a replica does not write replicated queries to the
slow query log. To change this, enable the
<a class="link" href="replication-options-replica.html#sysvar_log_slow_replica_statements">
<code class="literal">
log_slow_replica_statements
</code>
</a>
system variable. Note that if row-based replication is in use
(
<a class="link" href="replication-options-binary-log.html#sysvar_binlog_format">
<code class="literal">
binlog_format=ROW
</code>
</a>
), these
system variables have no effect. Queries are only added to the
replica's slow query log when they are logged in statement
format in the binary log, that is, when
<a class="link" href="replication-options-binary-log.html#sysvar_binlog_format">
<code class="literal">
binlog_format=STATEMENT
</code>
</a>
is set,
or when
<a class="link" href="replication-options-binary-log.html#sysvar_binlog_format">
<code class="literal">
binlog_format=MIXED
</code>
</a>
is
set and the statement is logged in statement format. Slow
queries that are logged in row format when
<a class="link" href="replication-options-binary-log.html#sysvar_binlog_format">
<code class="literal">
binlog_format=MIXED
</code>
</a>
is set, or
that are logged when
<a class="link" href="replication-options-binary-log.html#sysvar_binlog_format">
<code class="literal">
binlog_format=ROW
</code>
</a>
is set, are
not added to the replica's slow query log, even if
<a class="link" href="replication-options-replica.html#sysvar_log_slow_replica_statements">
<code class="literal">
log_slow_replica_statements
</code>
</a>
is
enabled.
</p>
</div>
<div class="simplesect">
<div class="titlepage">
<div>
<div class="simple">
<h4 class="title">
<a name="slow-query-log-contents">
</a>
Slow Query Log Contents
</h4>
</div>
</div>
</div>
<p>
When the slow query log is enabled, the server writes output to
any destinations specified by the
<a class="link" href="server-system-variables.html#sysvar_log_output">
<code class="literal">
log_output
</code>
</a>
system variable. If
you enable the log, the server opens the log file and writes
startup messages to it. However, further logging of queries to
the file does not occur unless the
<code class="literal">
FILE
</code>
log
destination is selected. If the destination is
<code class="literal">
NONE
</code>
, the server writes no queries even if
the slow query log is enabled. Setting the log file name has no
effect on logging if
<code class="literal">
FILE
</code>
is not selected as
an output destination.
</p>
<p>
If the slow query log is enabled and
<code class="literal">
FILE
</code>
is
selected as an output destination, each statement written to the
log is preceded by a line that begins with a
<code class="literal">
#
</code>
character and has these fields (with all
fields on a single line):
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<code class="literal">
Query_time:
<em class="replaceable">
<code>
duration
</code>
</em>
</code>
</p>
<p>
The statement execution time in seconds.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Lock_time:
<em class="replaceable">
<code>
duration
</code>
</em>
</code>
</p>
<p>
The time to acquire locks in seconds.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Rows_sent:
<em class="replaceable">
<code>
N
</code>
</em>
</code>
</p>
<p>
The number of rows sent to the client.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Rows_examined:
<em class="replaceable">
<code>
</code>
</em>
</code>
</p>
<p>
The number of rows examined by the server layer (not
counting any processing internal to storage engines).
</p>
</li>
</ul>
</div>
<p>
Enabling the
<a class="link" href="server-system-variables.html#sysvar_log_slow_extra">
<code class="literal">
log_slow_extra
</code>
</a>
system variable causes the server to write the following extra
fields to
<code class="literal">
FILE
</code>
output in addition to those
just listed (
<code class="literal">
TABLE
</code>
output is unaffected).
Some field descriptions refer to status variable names. Consult
the status variable descriptions for more information. However,
in the slow query log, the counters are per-statement values,
not cumulative per-session values.
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>
<code class="literal">
Thread_id:
<em class="replaceable">
<code>
ID
</code>
</em>
</code>
</p>
<p>
The statement thread identifier.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Errno:
<em class="replaceable">
<code>
error_number
</code>
</em>
</code>
</p>
<p>
The statement error number, or 0 if no error occurred.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Killed:
<em class="replaceable">
<code>
N
</code>
</em>
</code>
</p>
<p>
If the statement was terminated, the error number indicating
why, or 0 if the statement terminated normally.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Bytes_received:
<em class="replaceable">
<code>
N
</code>
</em>
</code>
</p>
<p>
The
<a class="link" href="server-status-variables.html#statvar_Bytes_received">
<code class="literal">
Bytes_received
</code>
</a>
value
for the statement.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Bytes_sent:
<em class="replaceable">
<code>
N
</code>
</em>
</code>
</p>
<p>
The
<a class="link" href="server-status-variables.html#statvar_Bytes_sent">
<code class="literal">
Bytes_sent
</code>
</a>
value for
the statement.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Read_first:
<em class="replaceable">
<code>
N
</code>
</em>
</code>
</p>
<p>
The
<a class="link" href="server-status-variables.html#statvar_Handler_read_first">
<code class="literal">
Handler_read_first
</code>
</a>
value for the statement.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Read_last:
<em class="replaceable">
<code>
N
</code>
</em>
</code>
</p>
<p>
The
<a class="link" href="server-status-variables.html#statvar_Handler_read_last">
<code class="literal">
Handler_read_last
</code>
</a>
value for the statement.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Read_key:
<em class="replaceable">
<code>
N
</code>
</em>
</code>
</p>
<p>
The
<a class="link" href="server-status-variables.html#statvar_Handler_read_key">
<code class="literal">
Handler_read_key
</code>
</a>
value
for the statement.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Read_next:
<em class="replaceable">
<code>
N
</code>
</em>
</code>
</p>
<p>
The
<a class="link" href="server-status-variables.html#statvar_Handler_read_next">
<code class="literal">
Handler_read_next
</code>
</a>
value for the statement.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Read_prev:
<em class="replaceable">
<code>
N
</code>
</em>
</code>
</p>
<p>
The
<a class="link" href="server-status-variables.html#statvar_Handler_read_prev">
<code class="literal">
Handler_read_prev
</code>
</a>
value for the statement.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Read_rnd:
<em class="replaceable">
<code>
N
</code>
</em>
</code>
</p>
<p>
The
<a class="link" href="server-status-variables.html#statvar_Handler_read_rnd">
<code class="literal">
Handler_read_rnd
</code>
</a>
value
for the statement.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Read_rnd_next:
<em class="replaceable">
<code>
N
</code>
</em>
</code>
</p>
<p>
The
<a class="link" href="server-status-variables.html#statvar_Handler_read_rnd_next">
<code class="literal">
Handler_read_rnd_next
</code>
</a>
value for the statement.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Sort_merge_passes:
<em class="replaceable">
<code>
N
</code>
</em>
</code>
</p>
<p>
The
<a class="link" href="server-status-variables.html#statvar_Sort_merge_passes">
<code class="literal">
Sort_merge_passes
</code>
</a>
value for the statement.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Sort_range_count:
<em class="replaceable">
<code>
N
</code>
</em>
</code>
</p>
<p>
The
<a class="link" href="server-status-variables.html#statvar_Sort_range">
<code class="literal">
Sort_range
</code>
</a>
value for
the statement.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Sort_rows:
<em class="replaceable">
<code>
N
</code>
</em>
</code>
</p>
<p>
The
<a class="link" href="server-status-variables.html#statvar_Sort_rows">
<code class="literal">
Sort_rows
</code>
</a>
value for
the statement.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Sort_scan_count:
<em class="replaceable">
<code>
N
</code>
</em>
</code>
</p>
<p>
The
<a class="link" href="server-status-variables.html#statvar_Sort_scan">
<code class="literal">
Sort_scan
</code>
</a>
value for
the statement.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Created_tmp_disk_tables:
<em class="replaceable">
<code>
N
</code>
</em>
</code>
</p>
<p>
The
<a class="link" href="server-status-variables.html#statvar_Created_tmp_disk_tables">
<code class="literal">
Created_tmp_disk_tables
</code>
</a>
value for the statement.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Created_tmp_tables:
<em class="replaceable">
<code>
N
</code>
</em>
</code>
</p>
<p>
The
<a class="link" href="server-status-variables.html#statvar_Created_tmp_tables">
<code class="literal">
Created_tmp_tables
</code>
</a>
value for the statement.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
Start:
<em class="replaceable">
<code>
timestamp
</code>
</em>
</code>
</p>
<p>
The statement execution start time.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
End:
<em class="replaceable">
<code>
timestamp
</code>
</em>
</code>
</p>
<p>
The statement execution end time.
</p>
</li>
</ul>
</div>
<p>
A given slow query log file may contain a mix of lines with and
without the extra fields added by enabling
<a class="link" href="server-system-variables.html#sysvar_log_slow_extra">
<code class="literal">
log_slow_extra
</code>
</a>
. Log file
analyzers can determine whether a line contains the additional
fields by the field count.
</p>
<p>
Each statement written to the slow query log file is preceded by
a
<a class="link" href="set-variable.html" title="15.7.6.1 SET Syntax for Variable Assignment">
<code class="literal">
SET
</code>
</a>
statement that includes a timestamp, which indicates when the
slow statement began executing.
</p>
<p>
Passwords in statements written to the slow query log are
rewritten by the server not to occur literally in plain text.
See
<a class="xref" href="password-logging.html" title="8.1.2.3 Passwords and Logging">
Section 8.1.2.3, “Passwords and Logging”
</a>
.
</p>
<p>
Statements that cannot be parsed (due, for example, to syntax
errors) are not written to the slow query log.
</p>
</div>
</div>
<br/>
</div>
|
https://dev.mysql.com/doc/refman/8.4/en/json-search-functions.html | <div id="docs-body">
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="json-search-functions">
</a>
14.17.3 Functions That Search JSON Values
</h3>
</div>
</div>
</div>
<p>
The functions in this section perform search or comparison
operations on JSON values to extract data from them, report
whether data exists at a location within them, or report the path
to data within them. The
<a class="link" href="json-search-functions.html#operator_member-of">
<code class="literal">
MEMBER OF()
</code>
</a>
operator is also documented herein.
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<a name="function_json-contains">
</a>
<p>
<a class="link" href="json-search-functions.html#function_json-contains">
<code class="literal">
JSON_CONTAINS(
<em class="replaceable">
<code>
target
</code>
</em>
,
<em class="replaceable">
<code>
candidate
</code>
</em>
[,
<em class="replaceable">
<code>
path
</code>
</em>
])
</code>
</a>
</p>
<a class="indexterm" name="idm46045195618768">
</a>
<p>
Indicates by returning 1 or 0 whether a given
<em class="replaceable">
<code>
candidate
</code>
</em>
JSON document is
contained within a
<em class="replaceable">
<code>
target
</code>
</em>
JSON
document, or—if a
<em class="replaceable">
<code>
path
</code>
</em>
argument was supplied—whether the candidate is found at
a specific path within the target. Returns
<code class="literal">
NULL
</code>
if any argument is
<code class="literal">
NULL
</code>
, or if the path argument does not
identify a section of the target document. An error occurs if
<em class="replaceable">
<code>
target
</code>
</em>
or
<em class="replaceable">
<code>
candidate
</code>
</em>
is not a valid JSON
document, or if the
<em class="replaceable">
<code>
path
</code>
</em>
argument
is not a valid path expression or contains a
<code class="literal">
*
</code>
or
<code class="literal">
**
</code>
wildcard.
</p>
<p>
To check only whether any data exists at the path, use
<a class="link" href="json-search-functions.html#function_json-contains-path">
<code class="literal">
JSON_CONTAINS_PATH()
</code>
</a>
instead.
</p>
<p>
The following rules define containment:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
A candidate scalar is contained in a target scalar if and
only if they are comparable and are equal. Two scalar
values are comparable if they have the same
<a class="link" href="json-attribute-functions.html#function_json-type">
<code class="literal">
JSON_TYPE()
</code>
</a>
types, with the
exception that values of types
<code class="literal">
INTEGER
</code>
and
<code class="literal">
DECIMAL
</code>
are also comparable to each
other.
</p>
</li>
<li class="listitem">
<p>
A candidate array is contained in a target array if and
only if every element in the candidate is contained in
some element of the target.
</p>
</li>
<li class="listitem">
<p>
A candidate nonarray is contained in a target array if and
only if the candidate is contained in some element of the
target.
</p>
</li>
<li class="listitem">
<p>
A candidate object is contained in a target object if and
only if for each key in the candidate there is a key with
the same name in the target and the value associated with
the candidate key is contained in the value associated
with the target key.
</p>
</li>
</ul>
</div>
<p>
Otherwise, the candidate value is not contained in the target
document.
</p>
<p>
Queries using
<code class="literal">
JSON_CONTAINS()
</code>
on
<a class="link" href="innodb-storage-engine.html" title="Chapter 17 The InnoDB Storage Engine">
<code class="literal">
InnoDB
</code>
</a>
tables can be optimized
using multi-valued indexes; see
<a class="xref" href="create-index.html#create-index-multi-valued" title="Multi-Valued Indexes">
Multi-Valued Indexes
</a>
, for more
information.
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa46011581"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SET</span> <span class="token variable">@j</span> <span class="token operator">=</span> <span class="token string">'{"a": 1, "b": 2, "c": {"d": 4}}'</span><span class="token punctuation">;</span>
<span class="token prompt">mysql></span> <span class="token keyword">SET</span> <span class="token variable">@j2</span> <span class="token operator">=</span> <span class="token string">'1'</span><span class="token punctuation">;</span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">JSON_CONTAINS</span><span class="token punctuation">(</span><span class="token variable">@j</span><span class="token punctuation">,</span> <span class="token variable">@j2</span><span class="token punctuation">,</span> <span class="token string">'$.a'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> JSON_CONTAINS(@j, @j2, '$.a') <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> 1 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">JSON_CONTAINS</span><span class="token punctuation">(</span><span class="token variable">@j</span><span class="token punctuation">,</span> <span class="token variable">@j2</span><span class="token punctuation">,</span> <span class="token string">'$.b'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> JSON_CONTAINS(@j, @j2, '$.b') <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> 0 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token prompt">mysql></span> <span class="token keyword">SET</span> <span class="token variable">@j2</span> <span class="token operator">=</span> <span class="token string">'{"d": 4}'</span><span class="token punctuation">;</span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">JSON_CONTAINS</span><span class="token punctuation">(</span><span class="token variable">@j</span><span class="token punctuation">,</span> <span class="token variable">@j2</span><span class="token punctuation">,</span> <span class="token string">'$.a'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> JSON_CONTAINS(@j, @j2, '$.a') <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> 0 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">JSON_CONTAINS</span><span class="token punctuation">(</span><span class="token variable">@j</span><span class="token punctuation">,</span> <span class="token variable">@j2</span><span class="token punctuation">,</span> <span class="token string">'$.c'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> JSON_CONTAINS(@j, @j2, '$.c') <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> 1 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span></code></pre>
</div>
</li>
<li class="listitem">
<a name="function_json-contains-path">
</a>
<p>
<a class="link" href="json-search-functions.html#function_json-contains-path">
<code class="literal">
JSON_CONTAINS_PATH(
<em class="replaceable">
<code>
json_doc
</code>
</em>
,
<em class="replaceable">
<code>
one_or_all
</code>
</em>
,
<em class="replaceable">
<code>
path
</code>
</em>
[,
<em class="replaceable">
<code>
path
</code>
</em>
] ...)
</code>
</a>
</p>
<a class="indexterm" name="idm46045195581872">
</a>
<p>
Returns 0 or 1 to indicate whether a JSON document contains
data at a given path or paths. Returns
<code class="literal">
NULL
</code>
if any argument is
<code class="literal">
NULL
</code>
. An error occurs if
the
<em class="replaceable">
<code>
json_doc
</code>
</em>
argument is not a
valid JSON document, any
<em class="replaceable">
<code>
path
</code>
</em>
argument is not a valid path expression, or
<em class="replaceable">
<code>
one_or_all
</code>
</em>
is not
<code class="literal">
'one'
</code>
or
<code class="literal">
'all'
</code>
.
</p>
<p>
To check for a specific value at a path, use
<a class="link" href="json-search-functions.html#function_json-contains">
<code class="literal">
JSON_CONTAINS()
</code>
</a>
instead.
</p>
<p>
The return value is 0 if no specified path exists within the
document. Otherwise, the return value depends on the
<em class="replaceable">
<code>
one_or_all
</code>
</em>
argument:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
<code class="literal">
'one'
</code>
: 1 if at least one path exists
within the document, 0 otherwise.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
'all'
</code>
: 1 if all paths exist within the
document, 0 otherwise.
</p>
</li>
</ul>
</div>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa35594254"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SET</span> <span class="token variable">@j</span> <span class="token operator">=</span> <span class="token string">'{"a": 1, "b": 2, "c": {"d": 4}}'</span><span class="token punctuation">;</span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">JSON_CONTAINS_PATH</span><span class="token punctuation">(</span><span class="token variable">@j</span><span class="token punctuation">,</span> <span class="token string">'one'</span><span class="token punctuation">,</span> <span class="token string">'$.a'</span><span class="token punctuation">,</span> <span class="token string">'$.e'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> JSON_CONTAINS_PATH(@j, 'one', '$.a', '$.e') <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> 1 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">JSON_CONTAINS_PATH</span><span class="token punctuation">(</span><span class="token variable">@j</span><span class="token punctuation">,</span> <span class="token string">'all'</span><span class="token punctuation">,</span> <span class="token string">'$.a'</span><span class="token punctuation">,</span> <span class="token string">'$.e'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> JSON_CONTAINS_PATH(@j, 'all', '$.a', '$.e') <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> 0 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">JSON_CONTAINS_PATH</span><span class="token punctuation">(</span><span class="token variable">@j</span><span class="token punctuation">,</span> <span class="token string">'one'</span><span class="token punctuation">,</span> <span class="token string">'$.c.d'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> JSON_CONTAINS_PATH(@j, 'one', '$.c.d') <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> 1 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">JSON_CONTAINS_PATH</span><span class="token punctuation">(</span><span class="token variable">@j</span><span class="token punctuation">,</span> <span class="token string">'one'</span><span class="token punctuation">,</span> <span class="token string">'$.a.d'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> JSON_CONTAINS_PATH(@j, 'one', '$.a.d') <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> 0 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span></code></pre>
</div>
</li>
<li class="listitem">
<a name="function_json-extract">
</a>
<p>
<a class="link" href="json-search-functions.html#function_json-extract">
<code class="literal">
JSON_EXTRACT(
<em class="replaceable">
<code>
json_doc
</code>
</em>
,
<em class="replaceable">
<code>
path
</code>
</em>
[,
<em class="replaceable">
<code>
path
</code>
</em>
] ...)
</code>
</a>
</p>
<a class="indexterm" name="idm46045195555088">
</a>
<p>
Returns data from a JSON document, selected from the parts of
the document matched by the
<em class="replaceable">
<code>
path
</code>
</em>
arguments. Returns
<code class="literal">
NULL
</code>
if any argument is
<code class="literal">
NULL
</code>
or no paths locate a value in the
document. An error occurs if the
<em class="replaceable">
<code>
json_doc
</code>
</em>
argument is not a valid
JSON document or any
<em class="replaceable">
<code>
path
</code>
</em>
argument
is not a valid path expression.
</p>
<p>
The return value consists of all values matched by the
<em class="replaceable">
<code>
path
</code>
</em>
arguments. If it is possible
that those arguments could return multiple values, the matched
values are autowrapped as an array, in the order corresponding
to the paths that produced them. Otherwise, the return value
is the single matched value.
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa78997611"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">JSON_EXTRACT</span><span class="token punctuation">(</span><span class="token string">'[10, 20, [30, 40]]'</span><span class="token punctuation">,</span> <span class="token string">'$[1]'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> JSON_EXTRACT('[10, 20, [30, 40]]', '$[1]') <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> 20 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">JSON_EXTRACT</span><span class="token punctuation">(</span><span class="token string">'[10, 20, [30, 40]]'</span><span class="token punctuation">,</span> <span class="token string">'$[1]'</span><span class="token punctuation">,</span> <span class="token string">'$[0]'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> JSON_EXTRACT('[10, 20, [30, 40]]', '$[1]', '$[0]') <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> [20, 10] <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">JSON_EXTRACT</span><span class="token punctuation">(</span><span class="token string">'[10, 20, [30, 40]]'</span><span class="token punctuation">,</span> <span class="token string">'$[2][*]'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> JSON_EXTRACT('[10, 20, [30, 40]]', '$[2][*]') <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> [30, 40] <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span></code></pre>
</div>
<p>
MySQL supports the
<a class="link" href="json-search-functions.html#operator_json-column-path">
<code class="literal">
->
</code>
</a>
operator as shorthand for this function as used with 2
arguments where the left hand side is a
<a class="link" href="json.html" title="13.5 The JSON Data Type">
<code class="literal">
JSON
</code>
</a>
column identifier (not an
expression) and the right hand side is the JSON path to be
matched within the column.
</p>
</li>
<li class="listitem">
<a name="operator_json-column-path">
</a>
<p>
<a class="link" href="json-search-functions.html#operator_json-column-path">
<code class="literal">
<em class="replaceable">
<code>
column
</code>
</em>
->
<em class="replaceable">
<code>
path
</code>
</em>
</code>
</a>
</p>
<a class="indexterm" name="idm46045195533904">
</a>
<p>
The
<a class="link" href="json-search-functions.html#operator_json-column-path">
<code class="literal">
->
</code>
</a>
operator serves as an alias for the
<a class="link" href="json-search-functions.html#function_json-extract">
<code class="literal">
JSON_EXTRACT()
</code>
</a>
function when
used with two arguments, a column identifier on the left and a
JSON path (a string literal) on the right that is evaluated
against the JSON document (the column value). You can use such
expressions in place of column references wherever they occur
in SQL statements.
</p>
<p>
The two
<a class="link" href="select.html" title="15.2.13 SELECT Statement">
<code class="literal">
SELECT
</code>
</a>
statements shown
here produce the same output:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa62677470"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> c<span class="token punctuation">,</span> <span class="token function">JSON_EXTRACT</span><span class="token punctuation">(</span>c<span class="token punctuation">,</span> <span class="token string">"$.id"</span><span class="token punctuation">)</span><span class="token punctuation">,</span> g
<span class="token operator">></span> <span class="token keyword">FROM</span> jemp
<span class="token operator">></span> <span class="token keyword">WHERE</span> <span class="token function">JSON_EXTRACT</span><span class="token punctuation">(</span>c<span class="token punctuation">,</span> <span class="token string">"$.id"</span><span class="token punctuation">)</span> <span class="token operator">></span> <span class="token number">1</span>
<span class="token operator">></span> <span class="token keyword">ORDER</span> <span class="token keyword">BY</span> <span class="token function">JSON_EXTRACT</span><span class="token punctuation">(</span>c<span class="token punctuation">,</span> <span class="token string">"$.name"</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> c <span class="token punctuation">|</span> c<span class="token punctuation">-</span>>"$.id" <span class="token punctuation">|</span> g <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> {"id": "3", "name": "Barney"} <span class="token punctuation">|</span> "3" <span class="token punctuation">|</span> 3 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> {"id": "4", "name": "Betty"} <span class="token punctuation">|</span> "4" <span class="token punctuation">|</span> 4 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> {"id": "2", "name": "Wilma"} <span class="token punctuation">|</span> "2" <span class="token punctuation">|</span> 2 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output">3 rows in set (0.00 sec)</span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> c<span class="token punctuation">,</span> c<span class="token operator">-</span><span class="token operator">></span><span class="token string">"$.id"</span><span class="token punctuation">,</span> g
<span class="token operator">></span> <span class="token keyword">FROM</span> jemp
<span class="token operator">></span> <span class="token keyword">WHERE</span> c<span class="token operator">-</span><span class="token operator">></span><span class="token string">"$.id"</span> <span class="token operator">></span> <span class="token number">1</span>
<span class="token operator">></span> <span class="token keyword">ORDER</span> <span class="token keyword">BY</span> c<span class="token operator">-</span><span class="token operator">></span><span class="token string">"$.name"</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> c <span class="token punctuation">|</span> c<span class="token punctuation">-</span>>"$.id" <span class="token punctuation">|</span> g <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> {"id": "3", "name": "Barney"} <span class="token punctuation">|</span> "3" <span class="token punctuation">|</span> 3 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> {"id": "4", "name": "Betty"} <span class="token punctuation">|</span> "4" <span class="token punctuation">|</span> 4 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> {"id": "2", "name": "Wilma"} <span class="token punctuation">|</span> "2" <span class="token punctuation">|</span> 2 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output">3 rows in set (0.00 sec)</span></code></pre>
</div>
<p>
This functionality is not limited to
<code class="literal">
SELECT
</code>
, as shown here:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa71362614"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">ALTER</span> <span class="token keyword">TABLE</span> jemp <span class="token keyword">ADD</span> <span class="token keyword">COLUMN</span> n <span class="token datatype">INT</span><span class="token punctuation">;</span>
<span class="token output">Query OK, 0 rows affected (0.68 sec)</span>
<span class="token output">Records: 0 Duplicates: 0 Warnings: 0</span>
<span class="token prompt">mysql></span> <span class="token keyword">UPDATE</span> jemp <span class="token keyword">SET</span> n<span class="token operator">=</span><span class="token number">1</span> <span class="token keyword">WHERE</span> c<span class="token operator">-</span><span class="token operator">></span><span class="token string">"$.id"</span> <span class="token operator">=</span> <span class="token string">"4"</span><span class="token punctuation">;</span>
<span class="token output">Query OK, 1 row affected (0.04 sec)</span>
<span class="token output">Rows matched: 1 Changed: 1 Warnings: 0</span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> c<span class="token punctuation">,</span> c<span class="token operator">-</span><span class="token operator">></span><span class="token string">"$.id"</span><span class="token punctuation">,</span> g<span class="token punctuation">,</span> n
<span class="token operator">></span> <span class="token keyword">FROM</span> jemp
<span class="token operator">></span> <span class="token keyword">WHERE</span> <span class="token function">JSON_EXTRACT</span><span class="token punctuation">(</span>c<span class="token punctuation">,</span> <span class="token string">"$.id"</span><span class="token punctuation">)</span> <span class="token operator">></span> <span class="token number">1</span>
<span class="token operator">></span> <span class="token keyword">ORDER</span> <span class="token keyword">BY</span> c<span class="token operator">-</span><span class="token operator">></span><span class="token string">"$.name"</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> c <span class="token punctuation">|</span> c<span class="token punctuation">-</span>>"$.id" <span class="token punctuation">|</span> g <span class="token punctuation">|</span> n <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> {"id": "3", "name": "Barney"} <span class="token punctuation">|</span> "3" <span class="token punctuation">|</span> 3 <span class="token punctuation">|</span> NULL <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> {"id": "4", "name": "Betty"} <span class="token punctuation">|</span> "4" <span class="token punctuation">|</span> 4 <span class="token punctuation">|</span> 1 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> {"id": "2", "name": "Wilma"} <span class="token punctuation">|</span> "2" <span class="token punctuation">|</span> 2 <span class="token punctuation">|</span> NULL <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output">3 rows in set (0.00 sec)</span>
<span class="token prompt">mysql></span> <span class="token keyword">DELETE</span> <span class="token keyword">FROM</span> jemp <span class="token keyword">WHERE</span> c<span class="token operator">-</span><span class="token operator">></span><span class="token string">"$.id"</span> <span class="token operator">=</span> <span class="token string">"4"</span><span class="token punctuation">;</span>
<span class="token output">Query OK, 1 row affected (0.04 sec)</span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> c<span class="token punctuation">,</span> c<span class="token operator">-</span><span class="token operator">></span><span class="token string">"$.id"</span><span class="token punctuation">,</span> g<span class="token punctuation">,</span> n
<span class="token operator">></span> <span class="token keyword">FROM</span> jemp
<span class="token operator">></span> <span class="token keyword">WHERE</span> <span class="token function">JSON_EXTRACT</span><span class="token punctuation">(</span>c<span class="token punctuation">,</span> <span class="token string">"$.id"</span><span class="token punctuation">)</span> <span class="token operator">></span> <span class="token number">1</span>
<span class="token operator">></span> <span class="token keyword">ORDER</span> <span class="token keyword">BY</span> c<span class="token operator">-</span><span class="token operator">></span><span class="token string">"$.name"</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> c <span class="token punctuation">|</span> c<span class="token punctuation">-</span>>"$.id" <span class="token punctuation">|</span> g <span class="token punctuation">|</span> n <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> {"id": "3", "name": "Barney"} <span class="token punctuation">|</span> "3" <span class="token punctuation">|</span> 3 <span class="token punctuation">|</span> NULL <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> {"id": "2", "name": "Wilma"} <span class="token punctuation">|</span> "2" <span class="token punctuation">|</span> 2 <span class="token punctuation">|</span> NULL <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output">2 rows in set (0.00 sec)</span></code></pre>
</div>
<p>
(See
<a class="xref" href="create-table-secondary-indexes.html#json-column-indirect-index" title="Indexing a Generated Column to Provide a JSON Column Index">
Indexing a Generated Column to Provide a JSON Column Index
</a>
, for the
statements used to create and populate the table just shown.)
</p>
<p>
This also works with JSON array values, as shown here:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa59256119"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">CREATE</span> <span class="token keyword">TABLE</span> tj10 <span class="token punctuation">(</span>a <span class="token datatype">JSON</span><span class="token punctuation">,</span> b <span class="token datatype">INT</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output">Query OK, 0 rows affected (0.26 sec)</span>
<span class="token prompt">mysql></span> <span class="token keyword">INSERT</span> <span class="token keyword">INTO</span> tj10
<span class="token operator">></span> <span class="token keyword">VALUES</span> <span class="token punctuation">(</span><span class="token string">"[3,10,5,17,44]"</span><span class="token punctuation">,</span> <span class="token number">33</span><span class="token punctuation">)</span><span class="token punctuation">,</span> <span class="token punctuation">(</span><span class="token string">"[3,10,5,17,[22,44,66]]"</span><span class="token punctuation">,</span> <span class="token number">0</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output">Query OK, 1 row affected (0.04 sec)</span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> a<span class="token operator">-</span><span class="token operator">></span><span class="token string">"$[4]"</span> <span class="token keyword">FROM</span> tj10<span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> a<span class="token punctuation">-</span>>"$[4]" <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> 44 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> [22, 44, 66] <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output">2 rows in set (0.00 sec)</span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token operator">*</span> <span class="token keyword">FROM</span> tj10 <span class="token keyword">WHERE</span> a<span class="token operator">-</span><span class="token operator">></span><span class="token string">"$[0]"</span> <span class="token operator">=</span> <span class="token number">3</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> a <span class="token punctuation">|</span> b <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> [3, 10, 5, 17, 44] <span class="token punctuation">|</span> 33 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> [3, 10, 5, 17, [22, 44, 66]] <span class="token punctuation">|</span> 0 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output">2 rows in set (0.00 sec)</span></code></pre>
</div>
<p>
Nested arrays are supported. An expression using
<code class="literal">
->
</code>
evaluates as
<code class="literal">
NULL
</code>
if no matching key is found in the target JSON document, as
shown here:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa90536545"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token operator">*</span> <span class="token keyword">FROM</span> tj10 <span class="token keyword">WHERE</span> a<span class="token operator">-</span><span class="token operator">></span><span class="token string">"$[4][1]"</span> <span class="token operator">IS</span> <span class="token operator">NOT</span> <span class="token boolean">NULL</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> a <span class="token punctuation">|</span> b <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> [3, 10, 5, 17, [22, 44, 66]] <span class="token punctuation">|</span> 0 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> a<span class="token operator">-</span><span class="token operator">></span><span class="token string">"$[4][1]"</span> <span class="token keyword">FROM</span> tj10<span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> a<span class="token punctuation">-</span>>"$[4][1]" <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> NULL <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> 44 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output">2 rows in set (0.00 sec)</span></code></pre>
</div>
<p>
This is the same behavior as seen in such cases when using
<code class="literal">
JSON_EXTRACT()
</code>
:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa86285933"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">JSON_EXTRACT</span><span class="token punctuation">(</span>a<span class="token punctuation">,</span> <span class="token string">"$[4][1]"</span><span class="token punctuation">)</span> <span class="token keyword">FROM</span> tj10<span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> JSON_EXTRACT(a, "$[4][1]") <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> NULL <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> 44 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output">2 rows in set (0.00 sec)</span></code></pre>
</div>
</li>
<li class="listitem">
<a name="operator_json-inline-path">
</a>
<p>
<a class="link" href="json-search-functions.html#operator_json-inline-path">
<code class="literal">
<em class="replaceable">
<code>
column
</code>
</em>
->>
<em class="replaceable">
<code>
path
</code>
</em>
</code>
</a>
</p>
<a class="indexterm" name="idm46045195483232">
</a>
<p>
This is an improved, unquoting extraction operator. Whereas
the
<code class="literal">
->
</code>
operator simply extracts a value,
the
<code class="literal">
->>
</code>
operator in addition unquotes
the extracted result. In other words, given a
<a class="link" href="json.html" title="13.5 The JSON Data Type">
<code class="literal">
JSON
</code>
</a>
column value
<em class="replaceable">
<code>
column
</code>
</em>
and a path expression
<em class="replaceable">
<code>
path
</code>
</em>
(a string literal), the
following three expressions return the same value:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
<a class="link" href="json-modification-functions.html#function_json-unquote">
<code class="literal">
JSON_UNQUOTE(
</code>
</a>
<a class="link" href="json-search-functions.html#function_json-extract">
<code class="literal">
JSON_EXTRACT(
<em class="replaceable">
<code>
column
</code>
</em>
,
<em class="replaceable">
<code>
path
</code>
</em>
) )
</code>
</a>
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
JSON_UNQUOTE(
<em class="replaceable">
<code>
column
</code>
</em>
</code>
<a class="link" href="json-search-functions.html#operator_json-column-path">
<code class="literal">
->
</code>
</a>
<code class="literal">
<em class="replaceable">
<code>
path
</code>
</em>
)
</code>
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
<em class="replaceable">
<code>
column
</code>
</em>
->>
<em class="replaceable">
<code>
path
</code>
</em>
</code>
</p>
</li>
</ul>
</div>
<p>
The
<code class="literal">
->>
</code>
operator can be used wherever
<code class="literal">
JSON_UNQUOTE(JSON_EXTRACT())
</code>
would be
allowed. This includes (but is not limited to)
<code class="literal">
SELECT
</code>
lists,
<code class="literal">
WHERE
</code>
and
<code class="literal">
HAVING
</code>
clauses, and
<code class="literal">
ORDER
BY
</code>
and
<code class="literal">
GROUP BY
</code>
clauses.
</p>
<p>
The next few statements demonstrate some
<code class="literal">
->>
</code>
operator equivalences with other
expressions in the
<a class="link" href="mysql.html" title="6.5.1 mysql — The MySQL Command-Line Client">
<span class="command">
<strong>
mysql
</strong>
</span>
</a>
client:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa38298552"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token operator">*</span> <span class="token keyword">FROM</span> jemp <span class="token keyword">WHERE</span> g <span class="token operator">></span> <span class="token number">2</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> c <span class="token punctuation">|</span> g <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> {"id": "3", "name": "Barney"} <span class="token punctuation">|</span> 3 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> {"id": "4", "name": "Betty"} <span class="token punctuation">|</span> 4 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output">2 rows in set (0.01 sec)</span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> c<span class="token operator">-</span><span class="token operator">></span><span class="token string">'$.name'</span> <span class="token keyword">AS</span> <span class="token keyword">name</span>
<span class="token prompt"> -></span> <span class="token keyword">FROM</span> jemp <span class="token keyword">WHERE</span> g <span class="token operator">></span> <span class="token number">2</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> name <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> "Barney" <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> "Betty" <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output">2 rows in set (0.00 sec)</span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">JSON_UNQUOTE</span><span class="token punctuation">(</span>c<span class="token operator">-</span><span class="token operator">></span><span class="token string">'$.name'</span><span class="token punctuation">)</span> <span class="token keyword">AS</span> <span class="token keyword">name</span>
<span class="token prompt"> -></span> <span class="token keyword">FROM</span> jemp <span class="token keyword">WHERE</span> g <span class="token operator">></span> <span class="token number">2</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> name <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> Barney <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> Betty <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output">2 rows in set (0.00 sec)</span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> c<span class="token operator">-</span><span class="token operator">>></span><span class="token string">'$.name'</span> <span class="token keyword">AS</span> <span class="token keyword">name</span>
<span class="token prompt"> -></span> <span class="token keyword">FROM</span> jemp <span class="token keyword">WHERE</span> g <span class="token operator">></span> <span class="token number">2</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> name <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> Barney <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> Betty <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output">2 rows in set (0.00 sec)</span></code></pre>
</div>
<p>
See
<a class="xref" href="create-table-secondary-indexes.html#json-column-indirect-index" title="Indexing a Generated Column to Provide a JSON Column Index">
Indexing a Generated Column to Provide a JSON Column Index
</a>
, for the SQL
statements used to create and populate the
<code class="literal">
jemp
</code>
table in the set of examples just
shown.
</p>
<p>
This operator can also be used with JSON arrays, as shown
here:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa8710476"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">CREATE</span> <span class="token keyword">TABLE</span> tj10 <span class="token punctuation">(</span>a <span class="token datatype">JSON</span><span class="token punctuation">,</span> b <span class="token datatype">INT</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output">Query OK, 0 rows affected (0.26 sec)</span>
<span class="token prompt">mysql></span> <span class="token keyword">INSERT</span> <span class="token keyword">INTO</span> tj10 <span class="token keyword">VALUES</span>
<span class="token prompt"> -></span> <span class="token punctuation">(</span><span class="token string">'[3,10,5,"x",44]'</span><span class="token punctuation">,</span> <span class="token number">33</span><span class="token punctuation">)</span><span class="token punctuation">,</span>
<span class="token prompt"> -></span> <span class="token punctuation">(</span><span class="token string">'[3,10,5,17,[22,"y",66]]'</span><span class="token punctuation">,</span> <span class="token number">0</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output">Query OK, 2 rows affected (0.04 sec)</span>
<span class="token output">Records: 2 Duplicates: 0 Warnings: 0</span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> a<span class="token operator">-</span><span class="token operator">></span><span class="token string">"$[3]"</span><span class="token punctuation">,</span> a<span class="token operator">-</span><span class="token operator">></span><span class="token string">"$[4][1]"</span> <span class="token keyword">FROM</span> tj10<span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> a<span class="token punctuation">-</span>>"$[3]" <span class="token punctuation">|</span> a<span class="token punctuation">-</span>>"$[4][1]" <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> "x" <span class="token punctuation">|</span> NULL <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> 17 <span class="token punctuation">|</span> "y" <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output">2 rows in set (0.00 sec)</span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> a<span class="token operator">-</span><span class="token operator">>></span><span class="token string">"$[3]"</span><span class="token punctuation">,</span> a<span class="token operator">-</span><span class="token operator">>></span><span class="token string">"$[4][1]"</span> <span class="token keyword">FROM</span> tj10<span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> a<span class="token punctuation">-</span>>>"$[3]" <span class="token punctuation">|</span> a<span class="token punctuation">-</span>>>"$[4][1]" <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> x <span class="token punctuation">|</span> NULL <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">|</span> 17 <span class="token punctuation">|</span> y <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output">2 rows in set (0.00 sec)</span></code></pre>
</div>
<p>
As with
<a class="link" href="json-search-functions.html#operator_json-column-path">
<code class="literal">
->
</code>
</a>
,
the
<code class="literal">
->>
</code>
operator is always expanded
in the output of
<a class="link" href="explain.html" title="15.8.2 EXPLAIN Statement">
<code class="literal">
EXPLAIN
</code>
</a>
, as
the following example demonstrates:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa78508136"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">EXPLAIN</span> <span class="token keyword">SELECT</span> c<span class="token operator">-</span><span class="token operator">>></span><span class="token string">'$.name'</span> <span class="token keyword">AS</span> <span class="token keyword">name</span>
<span class="token prompt"> -></span> <span class="token keyword">FROM</span> jemp <span class="token keyword">WHERE</span> g <span class="token operator">></span> <span class="token number">2</span>\G
<span class="token output"><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span> 1. row <span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span>
id<span class="token punctuation">:</span> 1
select_type<span class="token punctuation">:</span> SIMPLE
table<span class="token punctuation">:</span> jemp
partitions<span class="token punctuation">:</span> NULL
type<span class="token punctuation">:</span> range
possible_keys<span class="token punctuation">:</span> i
key<span class="token punctuation">:</span> i
key_len<span class="token punctuation">:</span> 5
ref<span class="token punctuation">:</span> NULL
rows<span class="token punctuation">:</span> 2
filtered<span class="token punctuation">:</span> 100.00
Extra<span class="token punctuation">:</span> Using where
</span><span class="token output">1 row in set, 1 warning (0.00 sec)</span>
<span class="token prompt">mysql></span> <span class="token keyword">SHOW</span> <span class="token keyword">WARNINGS</span>\G
<span class="token output"><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span> 1. row <span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span>
Level<span class="token punctuation">:</span> Note
Code<span class="token punctuation">:</span> 1003
Message<span class="token punctuation">:</span> /<span class="token punctuation">*</span> select#1 <span class="token punctuation">*</span>/ select
json_unquote(json_extract(`jtest`.`jemp`.`c`,'$.name')) AS `name` from
`jtest`.`jemp` where (`jtest`.`jemp`.`g` > 2)
</span><span class="token output">1 row in set (0.00 sec)</span></code></pre>
</div>
<p>
This is similar to how MySQL expands the
<a class="link" href="json-search-functions.html#operator_json-column-path">
<code class="literal">
->
</code>
</a>
operator in the same circumstances.
</p>
</li>
<li class="listitem">
<a name="function_json-keys">
</a>
<p>
<a class="link" href="json-search-functions.html#function_json-keys">
<code class="literal">
JSON_KEYS(
<em class="replaceable">
<code>
json_doc
</code>
</em>
[,
<em class="replaceable">
<code>
path
</code>
</em>
])
</code>
</a>
</p>
<a class="indexterm" name="idm46045195425568">
</a>
<p>
Returns the keys from the top-level value of a JSON object as
a JSON array, or, if a
<em class="replaceable">
<code>
path
</code>
</em>
argument is given, the top-level keys from the selected path.
Returns
<code class="literal">
NULL
</code>
if any argument is
<code class="literal">
NULL
</code>
, the
<em class="replaceable">
<code>
json_doc
</code>
</em>
argument is not an object,
or
<em class="replaceable">
<code>
path
</code>
</em>
, if given, does not locate
an object. An error occurs if the
<em class="replaceable">
<code>
json_doc
</code>
</em>
argument is not a valid
JSON document or the
<em class="replaceable">
<code>
path
</code>
</em>
argument
is not a valid path expression or contains a
<code class="literal">
*
</code>
or
<code class="literal">
**
</code>
wildcard.
</p>
<p>
The result array is empty if the selected object is empty. If
the top-level value has nested subobjects, the return value
does not include keys from those subobjects.
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa55156128"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">JSON_KEYS</span><span class="token punctuation">(</span><span class="token string">'{"a": 1, "b": {"c": 30}}'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> JSON_KEYS('{"a": 1, "b": {"c": 30}}') <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> ["a", "b"] <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">JSON_KEYS</span><span class="token punctuation">(</span><span class="token string">'{"a": 1, "b": {"c": 30}}'</span><span class="token punctuation">,</span> <span class="token string">'$.b'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> JSON_KEYS('{"a": 1, "b": {"c": 30}}', '$.b') <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> ["c"] <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span></code></pre>
</div>
</li>
<li class="listitem">
<a name="function_json-overlaps">
</a>
<p>
<a class="link" href="json-search-functions.html#function_json-overlaps">
<code class="literal">
JSON_OVERLAPS(
<em class="replaceable">
<code>
json_doc1
</code>
</em>
,
<em class="replaceable">
<code>
json_doc2
</code>
</em>
)
</code>
</a>
</p>
<a class="indexterm" name="idm46045195407008">
</a>
<p>
Compares two JSON documents. Returns true (1) if the two
document have any key-value pairs or array elements in common.
If both arguments are scalars, the function performs a simple
equality test. If either argument is
<code class="literal">
NULL
</code>
,
the function returns
<code class="literal">
NULL
</code>
.
</p>
<p>
This function serves as counterpart to
<a class="link" href="json-search-functions.html#function_json-contains">
<code class="literal">
JSON_CONTAINS()
</code>
</a>
, which requires
all elements of the array searched for to be present in the
array searched in. Thus,
<code class="literal">
JSON_CONTAINS()
</code>
performs an
<code class="literal">
AND
</code>
operation on search keys,
while
<code class="literal">
JSON_OVERLAPS()
</code>
performs an
<code class="literal">
OR
</code>
operation.
</p>
<p>
Queries on JSON columns of
<a class="link" href="innodb-storage-engine.html" title="Chapter 17 The InnoDB Storage Engine">
<code class="literal">
InnoDB
</code>
</a>
tables using
<code class="literal">
JSON_OVERLAPS()
</code>
in the
<code class="literal">
WHERE
</code>
clause can be optimized using
multi-valued indexes.
<a class="xref" href="create-index.html#create-index-multi-valued" title="Multi-Valued Indexes">
Multi-Valued Indexes
</a>
, provides detailed
information and examples.
</p>
<p>
When comparing two arrays,
<code class="literal">
JSON_OVERLAPS()
</code>
returns true if they share one or more array elements in
common, and false if they do not:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa66987347"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">JSON_OVERLAPS</span><span class="token punctuation">(</span><span class="token string">"[1,3,5,7]"</span><span class="token punctuation">,</span> <span class="token string">"[2,5,7]"</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> JSON_OVERLAPS("[1,3,5,7]", "[2,5,7]") <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> 1 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output">1 row in set (0.00 sec)</span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">JSON_OVERLAPS</span><span class="token punctuation">(</span><span class="token string">"[1,3,5,7]"</span><span class="token punctuation">,</span> <span class="token string">"[2,6,7]"</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> JSON_OVERLAPS("[1,3,5,7]", "[2,6,7]") <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> 1 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output">1 row in set (0.00 sec)</span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">JSON_OVERLAPS</span><span class="token punctuation">(</span><span class="token string">"[1,3,5,7]"</span><span class="token punctuation">,</span> <span class="token string">"[2,6,8]"</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> JSON_OVERLAPS("[1,3,5,7]", "[2,6,8]") <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> 0 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output">1 row in set (0.00 sec)</span></code></pre>
</div>
<p>
Partial matches are treated as no match, as shown here:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa35714680"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">JSON_OVERLAPS</span><span class="token punctuation">(</span><span class="token string">'[[1,2],[3,4],5]'</span><span class="token punctuation">,</span> <span class="token string">'[1,[2,3],[4,5]]'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> JSON_OVERLAPS('[[1,2],[3,4],5]', '[1,[2,3],[4,5]]') <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> 0 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output">1 row in set (0.00 sec)</span></code></pre>
</div>
<p>
When comparing objects, the result is true if they have at
least one key-value pair in common.
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa92327859"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">JSON_OVERLAPS</span><span class="token punctuation">(</span><span class="token string">'{"a":1,"b":10,"d":10}'</span><span class="token punctuation">,</span> <span class="token string">'{"c":1,"e":10,"f":1,"d":10}'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> JSON_OVERLAPS('{"a":1,"b":10,"d":10}', '{"c":1,"e":10,"f":1,"d":10}') <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> 1 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output">1 row in set (0.00 sec)</span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">JSON_OVERLAPS</span><span class="token punctuation">(</span><span class="token string">'{"a":1,"b":10,"d":10}'</span><span class="token punctuation">,</span> <span class="token string">'{"a":5,"e":10,"f":1,"d":20}'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> JSON_OVERLAPS('{"a":1,"b":10,"d":10}', '{"a":5,"e":10,"f":1,"d":20}') <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> 0 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output">1 row in set (0.00 sec)</span></code></pre>
</div>
<p>
If two scalars are used as the arguments to the function,
<code class="literal">
JSON_OVERLAPS()
</code>
performs a simple test for
equality:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa36986458"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">JSON_OVERLAPS</span><span class="token punctuation">(</span><span class="token string">'5'</span><span class="token punctuation">,</span> <span class="token string">'5'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> JSON_OVERLAPS('5', '5') <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> 1 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output">1 row in set (0.00 sec)</span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">JSON_OVERLAPS</span><span class="token punctuation">(</span><span class="token string">'5'</span><span class="token punctuation">,</span> <span class="token string">'6'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> JSON_OVERLAPS('5', '6') <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> 0 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output">1 row in set (0.00 sec)</span></code></pre>
</div>
<p>
When comparing a scalar with an array,
<code class="literal">
JSON_OVERLAPS()
</code>
attempts to treat the
scalar as an array element. In this example, the second
argument
<code class="literal">
6
</code>
is interpreted as
<code class="literal">
[6]
</code>
, as shown here:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa96946875"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">JSON_OVERLAPS</span><span class="token punctuation">(</span><span class="token string">'[4,5,6,7]'</span><span class="token punctuation">,</span> <span class="token string">'6'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> JSON_OVERLAPS('[4,5,6,7]', '6') <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> 1 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output">1 row in set (0.00 sec)</span></code></pre>
</div>
<p>
The function does not perform type conversions:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa31574571"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">JSON_OVERLAPS</span><span class="token punctuation">(</span><span class="token string">'[4,5,"6",7]'</span><span class="token punctuation">,</span> <span class="token string">'6'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> JSON_OVERLAPS('[4,5,"6",7]', '6') <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> 0 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output">1 row in set (0.00 sec)</span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">JSON_OVERLAPS</span><span class="token punctuation">(</span><span class="token string">'[4,5,6,7]'</span><span class="token punctuation">,</span> <span class="token string">'"6"'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> JSON_OVERLAPS('[4,5,6,7]', '"6"') <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> 0 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output">1 row in set (0.00 sec)</span></code></pre>
</div>
</li>
<li class="listitem">
<a name="function_json-search">
</a>
<p>
<a class="link" href="json-search-functions.html#function_json-search">
<code class="literal">
JSON_SEARCH(
<em class="replaceable">
<code>
json_doc
</code>
</em>
,
<em class="replaceable">
<code>
one_or_all
</code>
</em>
,
<em class="replaceable">
<code>
search_str
</code>
</em>
[,
<em class="replaceable">
<code>
escape_char
</code>
</em>
[,
<em class="replaceable">
<code>
path
</code>
</em>
] ...])
</code>
</a>
</p>
<a class="indexterm" name="idm46045195361664">
</a>
<p>
Returns the path to the given string within a JSON document.
Returns
<code class="literal">
NULL
</code>
if any of the
<em class="replaceable">
<code>
json_doc
</code>
</em>
,
<em class="replaceable">
<code>
search_str
</code>
</em>
, or
<em class="replaceable">
<code>
path
</code>
</em>
arguments are
<code class="literal">
NULL
</code>
; no
<em class="replaceable">
<code>
path
</code>
</em>
exists within the document; or
<em class="replaceable">
<code>
search_str
</code>
</em>
is not found. An error
occurs if the
<em class="replaceable">
<code>
json_doc
</code>
</em>
argument is
not a valid JSON document, any
<em class="replaceable">
<code>
path
</code>
</em>
argument is not a valid path expression,
<em class="replaceable">
<code>
one_or_all
</code>
</em>
is not
<code class="literal">
'one'
</code>
or
<code class="literal">
'all'
</code>
, or
<em class="replaceable">
<code>
escape_char
</code>
</em>
is not a constant
expression.
</p>
<p>
The
<em class="replaceable">
<code>
one_or_all
</code>
</em>
argument affects the
search as follows:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
<code class="literal">
'one'
</code>
: The search terminates after the
first match and returns one path string. It is undefined
which match is considered first.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
'all'
</code>
: The search returns all matching
path strings such that no duplicate paths are included. If
there are multiple strings, they are autowrapped as an
array. The order of the array elements is undefined.
</p>
</li>
</ul>
</div>
<p>
Within the
<em class="replaceable">
<code>
search_str
</code>
</em>
search string
argument, the
<code class="literal">
%
</code>
and
<code class="literal">
_
</code>
characters work as for the
<a class="link" href="string-comparison-functions.html#operator_like">
<code class="literal">
LIKE
</code>
</a>
operator:
<code class="literal">
%
</code>
matches any number of
characters (including zero characters), and
<code class="literal">
_
</code>
matches exactly one character.
</p>
<p>
To specify a literal
<code class="literal">
%
</code>
or
<code class="literal">
_
</code>
character in the search string, precede
it by the escape character. The default is
<code class="literal">
\
</code>
if the
<em class="replaceable">
<code>
escape_char
</code>
</em>
argument is missing or
<code class="literal">
NULL
</code>
. Otherwise,
<em class="replaceable">
<code>
escape_char
</code>
</em>
must be a constant that
is empty or one character.
</p>
<p>
For more information about matching and escape character
behavior, see the description of
<a class="link" href="string-comparison-functions.html#operator_like">
<code class="literal">
LIKE
</code>
</a>
in
<a class="xref" href="string-comparison-functions.html" title="14.8.1 String Comparison Functions and Operators">
Section 14.8.1, “String Comparison Functions and Operators”
</a>
. For escape
character handling, a difference from the
<a class="link" href="string-comparison-functions.html#operator_like">
<code class="literal">
LIKE
</code>
</a>
behavior is that the escape
character for
<a class="link" href="json-search-functions.html#function_json-search">
<code class="literal">
JSON_SEARCH()
</code>
</a>
must evaluate to a constant at compile time, not just at
execution time. For example, if
<a class="link" href="json-search-functions.html#function_json-search">
<code class="literal">
JSON_SEARCH()
</code>
</a>
is used in a
prepared statement and the
<em class="replaceable">
<code>
escape_char
</code>
</em>
argument is supplied
using a
<code class="literal">
?
</code>
parameter, the parameter value
might be constant at execution time, but is not at compile
time.
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa52897897"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SET</span> <span class="token variable">@j</span> <span class="token operator">=</span> <span class="token string">'["abc", [{"k": "10"}, "def"], {"x":"abc"}, {"y":"bcd"}]'</span><span class="token punctuation">;</span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">JSON_SEARCH</span><span class="token punctuation">(</span><span class="token variable">@j</span><span class="token punctuation">,</span> <span class="token string">'one'</span><span class="token punctuation">,</span> <span class="token string">'abc'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> JSON_SEARCH(@j, 'one', 'abc') <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> "$[0]" <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">JSON_SEARCH</span><span class="token punctuation">(</span><span class="token variable">@j</span><span class="token punctuation">,</span> <span class="token string">'all'</span><span class="token punctuation">,</span> <span class="token string">'abc'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> JSON_SEARCH(@j, 'all', 'abc') <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> ["$[0]", "$[2].x"] <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">JSON_SEARCH</span><span class="token punctuation">(</span><span class="token variable">@j</span><span class="token punctuation">,</span> <span class="token string">'all'</span><span class="token punctuation">,</span> <span class="token string">'ghi'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> JSON_SEARCH(@j, 'all', 'ghi') <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> NULL <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">JSON_SEARCH</span><span class="token punctuation">(</span><span class="token variable">@j</span><span class="token punctuation">,</span> <span class="token string">'all'</span><span class="token punctuation">,</span> <span class="token string">'10'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> JSON_SEARCH(@j, 'all', '10') <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> "$[1][0].k" <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">JSON_SEARCH</span><span class="token punctuation">(</span><span class="token variable">@j</span><span class="token punctuation">,</span> <span class="token string">'all'</span><span class="token punctuation">,</span> <span class="token string">'10'</span><span class="token punctuation">,</span> <span class="token boolean">NULL</span><span class="token punctuation">,</span> <span class="token string">'$'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> JSON_SEARCH(@j, 'all', '10', NULL, '$') <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> "$[1][0].k" <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">JSON_SEARCH</span><span class="token punctuation">(</span><span class="token variable">@j</span><span class="token punctuation">,</span> <span class="token string">'all'</span><span class="token punctuation">,</span> <span class="token string">'10'</span><span class="token punctuation">,</span> <span class="token boolean">NULL</span><span class="token punctuation">,</span> <span class="token string">'$[*]'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> JSON_SEARCH(@j, 'all', '10', NULL, '$[*]') <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> "$[1][0].k" <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">JSON_SEARCH</span><span class="token punctuation">(</span><span class="token variable">@j</span><span class="token punctuation">,</span> <span class="token string">'all'</span><span class="token punctuation">,</span> <span class="token string">'10'</span><span class="token punctuation">,</span> <span class="token boolean">NULL</span><span class="token punctuation">,</span> <span class="token string">'$**.k'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> JSON_SEARCH(@j, 'all', '10', NULL, '$**.k') <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> "$[1][0].k" <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">JSON_SEARCH</span><span class="token punctuation">(</span><span class="token variable">@j</span><span class="token punctuation">,</span> <span class="token string">'all'</span><span class="token punctuation">,</span> <span class="token string">'10'</span><span class="token punctuation">,</span> <span class="token boolean">NULL</span><span class="token punctuation">,</span> <span class="token string">'$[*][0].k'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> JSON_SEARCH(@j, 'all', '10', NULL, '$[*][0].k') <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> "$[1][0].k" <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">JSON_SEARCH</span><span class="token punctuation">(</span><span class="token variable">@j</span><span class="token punctuation">,</span> <span class="token string">'all'</span><span class="token punctuation">,</span> <span class="token string">'10'</span><span class="token punctuation">,</span> <span class="token boolean">NULL</span><span class="token punctuation">,</span> <span class="token string">'$[1]'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> JSON_SEARCH(@j, 'all', '10', NULL, '$[1]') <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> "$[1][0].k" <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">JSON_SEARCH</span><span class="token punctuation">(</span><span class="token variable">@j</span><span class="token punctuation">,</span> <span class="token string">'all'</span><span class="token punctuation">,</span> <span class="token string">'10'</span><span class="token punctuation">,</span> <span class="token boolean">NULL</span><span class="token punctuation">,</span> <span class="token string">'$[1][0]'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> JSON_SEARCH(@j, 'all', '10', NULL, '$[1][0]') <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> "$[1][0].k" <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">JSON_SEARCH</span><span class="token punctuation">(</span><span class="token variable">@j</span><span class="token punctuation">,</span> <span class="token string">'all'</span><span class="token punctuation">,</span> <span class="token string">'abc'</span><span class="token punctuation">,</span> <span class="token boolean">NULL</span><span class="token punctuation">,</span> <span class="token string">'$[2]'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> JSON_SEARCH(@j, 'all', 'abc', NULL, '$[2]') <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> "$[2].x" <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">JSON_SEARCH</span><span class="token punctuation">(</span><span class="token variable">@j</span><span class="token punctuation">,</span> <span class="token string">'all'</span><span class="token punctuation">,</span> <span class="token string">'%a%'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> JSON_SEARCH(@j, 'all', '%a%') <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> ["$[0]", "$[2].x"] <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">JSON_SEARCH</span><span class="token punctuation">(</span><span class="token variable">@j</span><span class="token punctuation">,</span> <span class="token string">'all'</span><span class="token punctuation">,</span> <span class="token string">'%b%'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> JSON_SEARCH(@j, 'all', '%b%') <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> ["$[0]", "$[2].x", "$[3].y"] <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">JSON_SEARCH</span><span class="token punctuation">(</span><span class="token variable">@j</span><span class="token punctuation">,</span> <span class="token string">'all'</span><span class="token punctuation">,</span> <span class="token string">'%b%'</span><span class="token punctuation">,</span> <span class="token boolean">NULL</span><span class="token punctuation">,</span> <span class="token string">'$[0]'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> JSON_SEARCH(@j, 'all', '%b%', NULL, '$[0]') <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> "$[0]" <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">JSON_SEARCH</span><span class="token punctuation">(</span><span class="token variable">@j</span><span class="token punctuation">,</span> <span class="token string">'all'</span><span class="token punctuation">,</span> <span class="token string">'%b%'</span><span class="token punctuation">,</span> <span class="token boolean">NULL</span><span class="token punctuation">,</span> <span class="token string">'$[2]'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> JSON_SEARCH(@j, 'all', '%b%', NULL, '$[2]') <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> "$[2].x" <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">JSON_SEARCH</span><span class="token punctuation">(</span><span class="token variable">@j</span><span class="token punctuation">,</span> <span class="token string">'all'</span><span class="token punctuation">,</span> <span class="token string">'%b%'</span><span class="token punctuation">,</span> <span class="token boolean">NULL</span><span class="token punctuation">,</span> <span class="token string">'$[1]'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> JSON_SEARCH(@j, 'all', '%b%', NULL, '$[1]') <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> NULL <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">JSON_SEARCH</span><span class="token punctuation">(</span><span class="token variable">@j</span><span class="token punctuation">,</span> <span class="token string">'all'</span><span class="token punctuation">,</span> <span class="token string">'%b%'</span><span class="token punctuation">,</span> <span class="token string">''</span><span class="token punctuation">,</span> <span class="token string">'$[1]'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> JSON_SEARCH(@j, 'all', '%b%', '', '$[1]') <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> NULL <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">JSON_SEARCH</span><span class="token punctuation">(</span><span class="token variable">@j</span><span class="token punctuation">,</span> <span class="token string">'all'</span><span class="token punctuation">,</span> <span class="token string">'%b%'</span><span class="token punctuation">,</span> <span class="token string">''</span><span class="token punctuation">,</span> <span class="token string">'$[3]'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> JSON_SEARCH(@j, 'all', '%b%', '', '$[3]') <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> "$[3].y" <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span></code></pre>
</div>
<p>
For more information about the JSON path syntax supported by
MySQL, including rules governing the wildcard operators
<code class="literal">
*
</code>
and
<code class="literal">
**
</code>
, see
<a class="xref" href="json.html#json-path-syntax" title="JSON Path Syntax">
JSON Path Syntax
</a>
.
</p>
</li>
<li class="listitem">
<a name="function_json-value">
</a>
<p>
<a class="link" href="json-search-functions.html#function_json-value">
<code class="literal">
JSON_VALUE(
<em class="replaceable">
<code>
json_doc
</code>
</em>
,
<em class="replaceable">
<code>
path
</code>
</em>
)
</code>
</a>
</p>
<a class="indexterm" name="idm46045195298224">
</a>
<p>
Extracts a value from a JSON document at the path given in the
specified document, and returns the extracted value,
optionally converting it to a desired type. The complete
syntax is shown here:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-clike"><div class="docs-select-all right" id="sa67366213"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-clike"><span class="token function">JSON_VALUE</span><span class="token punctuation">(</span><em class="replaceable">json_doc</em><span class="token punctuation">,</span> <em class="replaceable">path</em> <span class="token punctuation">[</span>RETURNING <em class="replaceable">type</em><span class="token punctuation">]</span> <span class="token punctuation">[</span><em class="replaceable">on_empty</em><span class="token punctuation">]</span> <span class="token punctuation">[</span><em class="replaceable">on_error</em><span class="token punctuation">]</span><span class="token punctuation">)</span>
<em class="replaceable">on_empty</em><span class="token punctuation">:</span>
<span class="token punctuation">{</span>NULL <span class="token operator">|</span> ERROR <span class="token operator">|</span> DEFAULT <em class="replaceable">value</em><span class="token punctuation">}</span> ON EMPTY
<em class="replaceable">on_error</em><span class="token punctuation">:</span>
<span class="token punctuation">{</span>NULL <span class="token operator">|</span> ERROR <span class="token operator">|</span> DEFAULT <em class="replaceable">value</em><span class="token punctuation">}</span> ON ERROR</code></pre>
</div>
<p>
<em class="replaceable">
<code>
json_doc
</code>
</em>
is a valid JSON document.
If this is
<code class="literal">
NULL
</code>
, the function returns
<code class="literal">
NULL
</code>
.
</p>
<p>
<em class="replaceable">
<code>
path
</code>
</em>
is a JSON path pointing to a
location in the document. This must be a string literal value.
</p>
<p>
<em class="replaceable">
<code>
type
</code>
</em>
is one of the following data
types:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
<a class="link" href="floating-point-types.html" title="13.1.4 Floating-Point Types (Approximate Value) - FLOAT, DOUBLE">
<code class="literal">
FLOAT
</code>
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="floating-point-types.html" title="13.1.4 Floating-Point Types (Approximate Value) - FLOAT, DOUBLE">
<code class="literal">
DOUBLE
</code>
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="fixed-point-types.html" title="13.1.3 Fixed-Point Types (Exact Value) - DECIMAL, NUMERIC">
<code class="literal">
DECIMAL
</code>
</a>
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
SIGNED
</code>
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
UNSIGNED
</code>
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="datetime.html" title="13.2.2 The DATE, DATETIME, and TIMESTAMP Types">
<code class="literal">
DATE
</code>
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="time.html" title="13.2.3 The TIME Type">
<code class="literal">
TIME
</code>
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="datetime.html" title="13.2.2 The DATE, DATETIME, and TIMESTAMP Types">
<code class="literal">
DATETIME
</code>
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="year.html" title="13.2.4 The YEAR Type">
<code class="literal">
YEAR
</code>
</a>
</p>
<p>
<code class="literal">
YEAR
</code>
values of one or two digits are
not supported.
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="char.html" title="13.3.2 The CHAR and VARCHAR Types">
<code class="literal">
CHAR
</code>
</a>
</p>
</li>
<li class="listitem">
<p>
<a class="link" href="json.html" title="13.5 The JSON Data Type">
<code class="literal">
JSON
</code>
</a>
</p>
</li>
</ul>
</div>
<p>
The types just listed are the same as the (non-array) types
supported by the
<a class="link" href="cast-functions.html#function_cast">
<code class="literal">
CAST()
</code>
</a>
function.
</p>
<p>
If not specified by a
<code class="literal">
RETURNING
</code>
clause, the
<code class="literal">
JSON_VALUE()
</code>
function's return type is
<a class="link" href="char.html" title="13.3.2 The CHAR and VARCHAR Types">
<code class="literal">
VARCHAR(512)
</code>
</a>
. When no character
set is specified for the return type,
<code class="literal">
JSON_VALUE()
</code>
uses
<code class="literal">
utf8mb4
</code>
with the binary collation, which is
case-sensitive; if
<code class="literal">
utf8mb4
</code>
is specified as
the character set for the result, the server uses the default
collation for this character set, which is not case-sensitive.
</p>
<p>
When the data at the specified path consists of or resolves to
a JSON null literal, the function returns SQL
<code class="literal">
NULL
</code>
.
</p>
<p>
<em class="replaceable">
<code>
on_empty
</code>
</em>
, if specified, determines
how
<code class="literal">
JSON_VALUE()
</code>
behaves when no data is
found at the path given; this clause takes one of the
following values:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
<code class="literal">
NULL ON EMPTY
</code>
: The function returns
<code class="literal">
NULL
</code>
; this is the default
<code class="literal">
ON
EMPTY
</code>
behavior.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
DEFAULT
<em class="replaceable">
<code>
value
</code>
</em>
ON
EMPTY
</code>
: the provided
<em class="replaceable">
<code>
value
</code>
</em>
is returned. The
value's type must match that of the return type.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
ERROR ON EMPTY
</code>
: The function throws an
error.
</p>
</li>
</ul>
</div>
<p>
If used,
<em class="replaceable">
<code>
on_error
</code>
</em>
takes one of the
following values with the corresponding outcome when an error
occurs, as listed here:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
<code class="literal">
NULL ON ERROR
</code>
:
<code class="literal">
JSON_VALUE()
</code>
returns
<code class="literal">
NULL
</code>
; this is the default behavior if
no
<code class="literal">
ON ERROR
</code>
clause is used.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
DEFAULT
<em class="replaceable">
<code>
value
</code>
</em>
ON
ERROR
</code>
: This is the value returned; its value
must match that of the return type.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
ERROR ON ERROR
</code>
: An error is thrown.
</p>
</li>
</ul>
</div>
<p>
<code class="literal">
ON EMPTY
</code>
, if used, must precede any
<code class="literal">
ON ERROR
</code>
clause. Specifying them in the
wrong order results in a syntax error.
</p>
<p>
<b>
Error handling.
</b>
In general, errors are handled by
<code class="literal">
JSON_VALUE()
</code>
as follows:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
<p>
All JSON input (document and path) is checked for
validity. If any of it is not valid, an SQL error is
thrown without triggering the
<code class="literal">
ON ERROR
</code>
clause.
</p>
</li>
<li class="listitem">
<p>
<code class="literal">
ON ERROR
</code>
is triggered whenever any of
the following events occur:
</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: square; ">
<li class="listitem">
<p>
Attempting to extract an object or an array, such as
that resulting from a path that resolves to multiple
locations within the JSON document
</p>
</li>
<li class="listitem">
<p>
Conversion errors, such as attempting to convert
<code class="literal">
'asdf'
</code>
to an
<code class="literal">
UNSIGNED
</code>
value
</p>
</li>
<li class="listitem">
<p>
Truncation of values
</p>
</li>
</ul>
</div>
</li>
<li class="listitem">
<p>
A conversion error always triggers a warning even if
<code class="literal">
NULL ON ERROR
</code>
or
<code class="literal">
DEFAULT ...
ON ERROR
</code>
is specified.
</p>
</li>
<li class="listitem">
<p>
The
<code class="literal">
ON EMPTY
</code>
clause is triggered when
the source JSON document (
<em class="replaceable">
<code>
expr
</code>
</em>
)
contains no data at the specified location
(
<em class="replaceable">
<code>
path
</code>
</em>
).
</p>
</li>
</ul>
</div>
<p>
<b>
Examples.
</b>
Two simple examples are shown here:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa18714107"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token keyword">JSON_VALUE</span><span class="token punctuation">(</span><span class="token string">'{"fname": "Joe", "lname": "Palmer"}'</span><span class="token punctuation">,</span> <span class="token string">'$.fname'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> JSON_VALUE('{"fname": "Joe", "lname": "Palmer"}', '$.fname') <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> Joe <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token keyword">JSON_VALUE</span><span class="token punctuation">(</span><span class="token string">'{"item": "shoes", "price": "49.95"}'</span><span class="token punctuation">,</span> <span class="token string">'$.price'</span>
<span class="token prompt"> -></span> <span class="token keyword">RETURNING</span> <span class="token datatype">DECIMAL</span><span class="token punctuation">(</span><span class="token number">4</span><span class="token punctuation">,</span><span class="token number">2</span><span class="token punctuation">)</span><span class="token punctuation">)</span> <span class="token keyword">AS</span> price<span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> price <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> 49.95 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span></code></pre>
</div>
<p>
The statement
<code class="literal">
SELECT
JSON_VALUE(
<em class="replaceable">
<code>
json_doc
</code>
</em>
,
<em class="replaceable">
<code>
path
</code>
</em>
RETURNING
<em class="replaceable">
<code>
type
</code>
</em>
)
</code>
is equivalent to
the following statement:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa57407821"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">SELECT</span> <span class="token function">CAST</span><span class="token punctuation">(</span>
<span class="token function">JSON_UNQUOTE</span><span class="token punctuation">(</span> <span class="token function">JSON_EXTRACT</span><span class="token punctuation">(</span><em class="replaceable">json_doc</em><span class="token punctuation">,</span> <span class="token keyword"><em class="replaceable">path</em></span><span class="token punctuation">)</span> <span class="token punctuation">)</span>
<span class="token keyword">AS</span> <span class="token keyword"><em class="replaceable">type</em></span>
<span class="token punctuation">)</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
<code class="literal">
JSON_VALUE()
</code>
simplifies creating indexes on
JSON columns by making it unnecessary in many cases to create
a generated column and then an index on the generated column.
You can do this when creating a table
<code class="literal">
t1
</code>
that has a
<a class="link" href="json.html" title="13.5 The JSON Data Type">
<code class="literal">
JSON
</code>
</a>
column by
creating an index on an expression that uses
<code class="literal">
JSON_VALUE()
</code>
operating on that column (with
a path that matches a value in that column), as shown here:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa37840751"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">CREATE</span> <span class="token keyword">TABLE</span> t1<span class="token punctuation">(</span>
j <span class="token datatype">JSON</span><span class="token punctuation">,</span>
<span class="token keyword">INDEX</span> i1 <span class="token punctuation">(</span> <span class="token punctuation">(</span><span class="token keyword">JSON_VALUE</span><span class="token punctuation">(</span>j<span class="token punctuation">,</span> <span class="token string">'$.id'</span> <span class="token keyword">RETURNING</span> <span class="token keyword">UNSIGNED</span><span class="token punctuation">)</span><span class="token punctuation">)</span> <span class="token punctuation">)</span>
<span class="token punctuation">)</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
The following
<a class="link" href="explain.html" title="15.8.2 EXPLAIN Statement">
<code class="literal">
EXPLAIN
</code>
</a>
output
shows that a query against
<code class="literal">
t1
</code>
employing the
index expression in the
<code class="literal">
WHERE
</code>
clause uses
the index thus created:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa38655372"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">EXPLAIN</span> <span class="token keyword">SELECT</span> <span class="token operator">*</span> <span class="token keyword">FROM</span> t1
<span class="token prompt"> -></span> <span class="token keyword">WHERE</span> <span class="token keyword">JSON_VALUE</span><span class="token punctuation">(</span>j<span class="token punctuation">,</span> <span class="token string">'$.id'</span> <span class="token keyword">RETURNING</span> <span class="token keyword">UNSIGNED</span><span class="token punctuation">)</span> <span class="token operator">=</span> <span class="token number">123</span>\G
<span class="token output"><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span> 1. row <span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span>
id<span class="token punctuation">:</span> 1
select_type<span class="token punctuation">:</span> SIMPLE
table<span class="token punctuation">:</span> t1
partitions<span class="token punctuation">:</span> NULL
type<span class="token punctuation">:</span> ref
possible_keys<span class="token punctuation">:</span> i1
key<span class="token punctuation">:</span> i1
key_len<span class="token punctuation">:</span> 9
ref<span class="token punctuation">:</span> const
rows<span class="token punctuation">:</span> 1
filtered<span class="token punctuation">:</span> 100.00
Extra<span class="token punctuation">:</span> NULL</span></code></pre>
</div>
<p>
This achieves much the same effect as creating a table
<code class="literal">
t2
</code>
with an index on a generated column (see
<a class="xref" href="create-table-secondary-indexes.html#json-column-indirect-index" title="Indexing a Generated Column to Provide a JSON Column Index">
Indexing a Generated Column to Provide a JSON Column Index
</a>
), like this one:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa21281829"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token keyword">CREATE</span> <span class="token keyword">TABLE</span> t2 <span class="token punctuation">(</span>
j <span class="token datatype">JSON</span><span class="token punctuation">,</span>
g <span class="token datatype">INT</span> <span class="token keyword">GENERATED</span> <span class="token keyword">ALWAYS</span> <span class="token keyword">AS</span> <span class="token punctuation">(</span>j<span class="token operator">-</span><span class="token operator">></span><span class="token string">"$.id"</span><span class="token punctuation">)</span><span class="token punctuation">,</span>
<span class="token keyword">INDEX</span> i1 <span class="token punctuation">(</span>g<span class="token punctuation">)</span>
<span class="token punctuation">)</span><span class="token punctuation">;</span></code></pre>
</div>
<p>
The
<a class="link" href="explain.html" title="15.8.2 EXPLAIN Statement">
<code class="literal">
EXPLAIN
</code>
</a>
output for a query
against this table, referencing the generated column, shows
that the index is used in the same way as for the previous
query against table
<code class="literal">
t1
</code>
:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa30158784"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">EXPLAIN</span> <span class="token keyword">SELECT</span> <span class="token operator">*</span> <span class="token keyword">FROM</span> t2 <span class="token keyword">WHERE</span> g <span class="token operator">=</span> <span class="token number">123</span>\G
<span class="token output"><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span> 1. row <span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span>
id<span class="token punctuation">:</span> 1
select_type<span class="token punctuation">:</span> SIMPLE
table<span class="token punctuation">:</span> t2
partitions<span class="token punctuation">:</span> NULL
type<span class="token punctuation">:</span> ref
possible_keys<span class="token punctuation">:</span> i1
key<span class="token punctuation">:</span> i1
key_len<span class="token punctuation">:</span> 5
ref<span class="token punctuation">:</span> const
rows<span class="token punctuation">:</span> 1
filtered<span class="token punctuation">:</span> 100.00
Extra<span class="token punctuation">:</span> NULL</span></code></pre>
</div>
<p>
For information about using indexes on generated columns for
indirect indexing of
<a class="link" href="json.html" title="13.5 The JSON Data Type">
<code class="literal">
JSON
</code>
</a>
columns, see
<a class="xref" href="create-table-secondary-indexes.html#json-column-indirect-index" title="Indexing a Generated Column to Provide a JSON Column Index">
Indexing a Generated Column to Provide a JSON Column Index
</a>
.
</p>
</li>
<li class="listitem">
<a name="operator_member-of">
</a>
<p>
<a class="link" href="json-search-functions.html#operator_member-of">
<code class="literal">
<em class="replaceable">
<code>
value
</code>
</em>
MEMBER OF(
<em class="replaceable">
<code>
json_array
</code>
</em>
)
</code>
</a>
</p>
<a class="indexterm" name="idm46045195183600">
</a>
<p>
Returns true (1) if
<em class="replaceable">
<code>
value
</code>
</em>
is an
element of
<em class="replaceable">
<code>
json_array
</code>
</em>
, otherwise
returns false (0).
<em class="replaceable">
<code>
value
</code>
</em>
must be a
scalar or a JSON document; if it is a scalar, the operator
attempts to treat it as an element of a JSON array. If
<em class="replaceable">
<code>
value
</code>
</em>
or
<em class="replaceable">
<code>
json_array
</code>
</em>
is
<em class="replaceable">
<code>
NULL
</code>
</em>
, the function returns
<em class="replaceable">
<code>
NULL
</code>
</em>
.
</p>
<p>
Queries using
<code class="literal">
MEMBER OF()
</code>
on JSON columns
of
<a class="link" href="innodb-storage-engine.html" title="Chapter 17 The InnoDB Storage Engine">
<code class="literal">
InnoDB
</code>
</a>
tables in the
<code class="literal">
WHERE
</code>
clause can be optimized using
multi-valued indexes. See
<a class="xref" href="create-index.html#create-index-multi-valued" title="Multi-Valued Indexes">
Multi-Valued Indexes
</a>
, for detailed
information and examples.
</p>
<p>
Simple scalars are treated as array values, as shown here:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa12558584"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token number">17</span> <span class="token function">MEMBER OF</span><span class="token punctuation">(</span><span class="token string">'[23, "abc", 17, "ab", 10]'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> 17 MEMBER OF('[23, "abc", 17, "ab", 10]') <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> 1 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output">1 row in set (0.00 sec)</span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token string">'ab'</span> <span class="token function">MEMBER OF</span><span class="token punctuation">(</span><span class="token string">'[23, "abc", 17, "ab", 10]'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> 'ab' MEMBER OF('[23, "abc", 17, "ab", 10]') <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> 1 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output">1 row in set (0.00 sec)</span></code></pre>
</div>
<p>
Partial matches of array element values do not match:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa55337714"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token number">7</span> <span class="token function">MEMBER OF</span><span class="token punctuation">(</span><span class="token string">'[23, "abc", 17, "ab", 10]'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> 7 MEMBER OF('[23, "abc", 17, "ab", 10]') <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> 0 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output">1 row in set (0.00 sec)</span></code></pre>
</div>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa55140092"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token string">'a'</span> <span class="token function">MEMBER OF</span><span class="token punctuation">(</span><span class="token string">'[23, "abc", 17, "ab", 10]'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> 'a' MEMBER OF('[23, "abc", 17, "ab", 10]') <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> 0 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output">1 row in set (0.00 sec)</span></code></pre>
</div>
<p>
Conversions to and from string types are not performed:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa47256905"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span>
<span class="token prompt"> -></span> <span class="token number">17</span> <span class="token function">MEMBER OF</span><span class="token punctuation">(</span><span class="token string">'[23, "abc", "17", "ab", 10]'</span><span class="token punctuation">)</span><span class="token punctuation">,</span>
<span class="token prompt"> -></span> <span class="token string">"17"</span> <span class="token function">MEMBER OF</span><span class="token punctuation">(</span><span class="token string">'[23, "abc", 17, "ab", 10]'</span><span class="token punctuation">)</span>\G
<span class="token output"><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span> 1. row <span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span><span class="token punctuation">*</span>
17 MEMBER OF('[23, "abc", "17", "ab", 10]')<span class="token punctuation">:</span> 0
"17" MEMBER OF('[23, "abc", 17, "ab", 10]')<span class="token punctuation">:</span> 0
</span><span class="token output">1 row in set (0.00 sec)</span></code></pre>
</div>
<p>
To use this operator with a value which itself an array, it is
necessary to cast it explicitly as a JSON array. You can do
this with
<a class="link" href="cast-functions.html#function_cast">
<code class="literal">
CAST(... AS JSON)
</code>
</a>
:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa88756253"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">CAST</span><span class="token punctuation">(</span><span class="token string">'[4,5]'</span> <span class="token keyword">AS</span> <span class="token datatype">JSON</span><span class="token punctuation">)</span> <span class="token function">MEMBER OF</span><span class="token punctuation">(</span><span class="token string">'[[3,4],[4,5]]'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> CAST('[4,5]' AS JSON) MEMBER OF('[[3,4],[4,5]]') <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> 1 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output">1 row in set (0.00 sec)</span></code></pre>
</div>
<p>
It is also possible to perform the necessary cast using the
<a class="link" href="json-creation-functions.html#function_json-array">
<code class="literal">
JSON_ARRAY()
</code>
</a>
function, like
this:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa5548151"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token function">JSON_ARRAY</span><span class="token punctuation">(</span><span class="token number">4</span><span class="token punctuation">,</span><span class="token number">5</span><span class="token punctuation">)</span> <span class="token function">MEMBER OF</span><span class="token punctuation">(</span><span class="token string">'[[3,4],[4,5]]'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> JSON_ARRAY(4,5) MEMBER OF('[[3,4],[4,5]]') <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> 1 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output">1 row in set (0.00 sec)</span></code></pre>
</div>
<p>
Any JSON objects used as values to be tested or which appear
in the target array must be coerced to the correct type using
<code class="literal">
CAST(... AS JSON)
</code>
or
<a class="link" href="json-creation-functions.html#function_json-object">
<code class="literal">
JSON_OBJECT()
</code>
</a>
. In addition, a
target array containing JSON objects must itself be cast using
<code class="literal">
JSON_ARRAY
</code>
. This is demonstrated in the
following sequence of statements:
</p>
<div class="copytoclipboard-wrapper">
<pre class="programlisting language-sql"><div class="docs-select-all right" id="sa10070717"><div class="copy-help left">Press ⌘+C to copy</div> <div class="right"><button class="clipboard-btn" title="Copy to Clipboard"><span class="icon-clipboard"></span></button></div></div><code class="language-sql"><span class="token prompt">mysql></span> <span class="token keyword">SET</span> <span class="token variable">@a</span> <span class="token operator">=</span> <span class="token function">CAST</span><span class="token punctuation">(</span><span class="token string">'{"a":1}'</span> <span class="token keyword">AS</span> <span class="token datatype">JSON</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output">Query OK, 0 rows affected (0.00 sec)</span>
<span class="token prompt">mysql></span> <span class="token keyword">SET</span> <span class="token variable">@b</span> <span class="token operator">=</span> <span class="token function">JSON_OBJECT</span><span class="token punctuation">(</span><span class="token string">"b"</span><span class="token punctuation">,</span> <span class="token number">2</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output">Query OK, 0 rows affected (0.00 sec)</span>
<span class="token prompt">mysql></span> <span class="token keyword">SET</span> <span class="token variable">@c</span> <span class="token operator">=</span> <span class="token function">JSON_ARRAY</span><span class="token punctuation">(</span><span class="token number">17</span><span class="token punctuation">,</span> <span class="token variable">@b</span><span class="token punctuation">,</span> <span class="token string">"abc"</span><span class="token punctuation">,</span> <span class="token variable">@a</span><span class="token punctuation">,</span> <span class="token number">23</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output">Query OK, 0 rows affected (0.00 sec)</span>
<span class="token prompt">mysql></span> <span class="token keyword">SELECT</span> <span class="token variable">@a</span> <span class="token function">MEMBER OF</span><span class="token punctuation">(</span><span class="token variable">@c</span><span class="token punctuation">)</span><span class="token punctuation">,</span> <span class="token variable">@b</span> <span class="token function">MEMBER OF</span><span class="token punctuation">(</span><span class="token variable">@c</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> @a MEMBER OF(@c) <span class="token punctuation">|</span> @b MEMBER OF(@c) <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output"><span class="token punctuation">|</span> 1 <span class="token punctuation">|</span> 1 <span class="token punctuation">|</span></span>
<span class="token output"><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">-</span><span class="token punctuation">+</span></span>
<span class="token output">1 row in set (0.00 sec)</span></code></pre>
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