CreateQuery tab (children 3)
 Identifier tab
 Columns definition (children 1)
  ExpressionList (children 3)
   ColumnDeclaration x (children 1)
    DataType UInt64
   ColumnDeclaration arr.a (children 1)
    DataType Array (children 1)
     ExpressionList (children 1)
      DataType UInt64
   ColumnDeclaration arr.b (children 1)
    DataType Array (children 1)
     ExpressionList (children 1)
      DataType UInt64
 Storage definition (children 2)
  Function MergeTree
  Identifier x
