src/llm_query.qmd

To use a Large Language Model (LLM) to create queries and Cypher (a query language for graph databases) queries to collect data from a Knowledge Graph and answer a user's question, follow these steps:

### **Understanding the User's Query**

The first step is to understand and interpret the user's natural language question. This involves:

- **Entity Recognition**: Identifying the key entities (e.g., characters, locations) mentioned in the user's query.

- **Intent Identification**: Determining what the user is asking for (e.g., relationships between entities, attributes of a specific entity).

For example, if the user asks, "Which house does Harry belong to?", the LLM needs to identify:

- **Entity**: "Harry"

- **Intent**: Finding the relationship between "Harry" and the "House" he belongs to.

### **Mapping the Query to the Knowledge Graph Schema**

Once the entities and intent are identified, the LLM needs to map these to the structure of the Knowledge Graph, which is defined by the ontology. This includes:

- **Identifying Nodes and Relationships**: Understanding which nodes (e.g., `Person`, `House`) and relationships (e.g., `BelongsTo`) in the graph are relevant to the query.

- **Mapping Entities to Nodes**: Associating the identified entities with the corresponding nodes in the graph.

For example:
- The entity "Harry" maps to the node `Person`.
- The intent of finding a "House" can be mapped to the relationship `BelongsTo`.

### **Generating the Cypher Query**

Cypher is the query language used to interact with Neo4j databases. The LLM can be used to generate a Cypher query based on the user's input and the knowledge graph schema.

#### **Basic Cypher Query Structure**

A typical Cypher query has the following structure:

```cypher
MATCH (n:Label)-[r:RELATIONSHIP]->(m:Label)
WHERE n.property = 'value'
RETURN m.property
```

Here’s how the LLM would translate the user's query into a Cypher query:

**User Query**: "Which house does Harry belong to?"

1. **MATCH Clause**: The LLM recognizes that "Harry" is a `Person` and that the relationship we're interested in is `BelongsTo` (connecting a `Person` to a `House`).

   ```cypher
   MATCH (harry:Person)-[:BelongsTo]->(house:House)
   ```

2. **WHERE Clause**: To filter the nodes to only include the one representing Harry.

   ```cypher
   WHERE harry.name = 'Harry'
   ```

3. **RETURN Clause**: Finally, return the name of the house.

   ```cypher
   RETURN house.name
   ```

**Final Cypher Query**:

```cypher
MATCH (harry:Person)-[:BelongsTo]->(house:House)
WHERE harry.name = 'Harry'
RETURN house.name
```

### **Executing the Query and Retrieving Results**

The generated Cypher query is then executed against the Knowledge Graph database (e.g., Neo4j). 

The database returns the result, which is typically in the form of a node or a set of nodes (in this case, the `House` node associated with `Harry`).

### **Interpreting and Formatting the Result**

After executing the query, the LLM needs to format the result in a user-friendly way. For example:
- If the result is "Gryffindor," the LLM might generate a response like, "Harry belongs to the Gryffindor house."

### **Handling Complex Queries**

For more complex queries, the LLM can generate more sophisticated Cypher queries by leveraging advanced Cypher features such as:

- **Multiple Relationships**: Handling queries that involve multiple relationships, such as "Who are Harry's friends that belong to Gryffindor?"

- **Aggregation**: Using functions like `COUNT`, `SUM`, etc., for queries that require aggregating data, like "How many students belong to Gryffindor?"

- **Pattern Matching**: Matching complex graph patterns to answer questions like "Which professors at Hogwarts teach Gryffindor students?"

#### **Example Complex Query**

**User Query**: "Who are Harry's friends that belong to Gryffindor?"

**Cypher Query**:
```cypher
MATCH (harry:Person)-[:FriendOf]->(friend:Person)-[:BelongsTo]->(house:House)
WHERE harry.name = 'Harry' AND house.name = 'Gryffindor'
RETURN friend.name
```

### **Continuous Learning and Adaptation**

The LLM can be fine-tuned over time to improve its ability to generate accurate Cypher queries. By analyzing the success or failure of past queries, the LLM can learn to better interpret user questions, understand the ontology, and generate more precise Cypher queries.

### **Feedback Loop and Iteration**

Users might provide feedback on the answers they receive, which can be used to further refine the LLM’s understanding of the domain and improve future query generation. This iterative process ensures that the LLM becomes more effective at interacting with the Knowledge Graph over time.

### Summary

By following these steps, an LLM can effectively generate Cypher queries to extract data from a Knowledge Graph and answer user questions. The process involves understanding the user’s intent, mapping that intent to the graph’s structure, generating the appropriate Cypher query, and then formatting the retrieved results in a user-friendly manner. This approach allows for a powerful and dynamic interaction between natural language queries and structured graph data.


### Bullet Points:

- **Understanding the User's Query**:
  - **Entity Recognition**: Identify key entities in the user's question (e.g., "Harry").
  - **Intent Identification**: Determine what the user is asking for (e.g., relationships, attributes).

- **Mapping the Query to the Knowledge Graph Schema**:
  - **Identifying Nodes and Relationships**: Determine relevant nodes (e.g., `Person`, `House`) and relationships (e.g., `BelongsTo`) in the graph.
  - **Mapping Entities to Nodes**: Associate identified entities with corresponding graph nodes.

- **Generating the Cypher Query**:
  - **Basic Cypher Structure**: Use a structured approach to create Cypher queries.
  - **Example**: Translate "Which house does Harry belong to?" into a Cypher query:
    ```cypher
    MATCH (harry:Person)-[:BelongsTo]->(house:House)
    WHERE harry.name = 'Harry'
    RETURN house.name
    ```

- **Executing the Query and Retrieving Results**:
  - **Query Execution**: Run the Cypher query against the Knowledge Graph database (e.g., Neo4j).
  - **Result Formatting**: Present the result in a user-friendly format (e.g., "Harry belongs to Gryffindor").

- **Handling Complex Queries**:
  - **Advanced Cypher Features**: Handle complex queries involving multiple relationships, aggregation, and pattern matching.
  - **Example**: "Who are Harry's friends that belong to Gryffindor?"
    ```cypher
    MATCH (harry:Person)-[:FriendOf]->(friend:Person)-[:BelongsTo]->(house:House)
    WHERE harry.name = 'Harry' AND house.name = 'Gryffindor'
    RETURN friend.name
    ```

- **Continuous Learning and Adaptation**:
  - **Fine-Tuning**: Improve query generation accuracy over time by learning from past successes and failures.

- **Feedback Loop and Iteration**:
  - **User Feedback**: Use feedback to refine the LLM's understanding and improve future query generation.

### Key Takeaways:

- LLMs can effectively translate natural language queries into Cypher queries by recognizing entities, understanding intent, and mapping these to a Knowledge Graph schema.
- By generating and executing precise Cypher queries, LLMs can retrieve and present data in response to user questions, enabling dynamic interaction with structured graph data.
- Continuous learning and user feedback are essential for refining the LLM's capabilities in query generation and knowledge graph interaction.