How pairs of objects are the same size and material?
return objects ;return number of  #1 for each size ;return #1 where #2 at least two ;return number of  #3 for each material ;return #1 where #4 at least two ;return number of  #5 ;return division of #6 and two
['select', 'group', 'comparative', 'group', 'comparative', 'aggregate', 'project']