CreateQuery tab1 (children 3)
 Identifier tab1
 Columns definition (children 1)
  ExpressionList (children 3)
   ColumnDeclaration a1 (children 1)
    DataType Int32
   ColumnDeclaration b1 (children 1)
    DataType Int32
   ColumnDeclaration val (children 1)
    DataType UInt64
 Storage definition (children 2)
  Function MergeTree
  Identifier a1