CreateQuery attach_partition_t6 (children 3)
 Identifier attach_partition_t6
 Columns definition (children 2)
  ExpressionList (children 2)
   ColumnDeclaration a (children 1)
    DataType UInt32
   ColumnDeclaration b (children 1)
    DataType String
  ExpressionList (children 1)
   Projection (children 1)
    ProjectionSelectQuery (children 2)
     ExpressionList (children 2)
      Identifier b
      Function sum (children 1)
       ExpressionList (children 1)
        Identifier a
     ExpressionList (children 1)
      Identifier b
 Storage definition (children 2)
  Function MergeTree
  Identifier a
