CreateQuery t1 (children 3)
 Identifier t1
 Columns definition (children 1)
  ExpressionList (children 2)
   ColumnDeclaration x (children 1)
    DataType UInt32
   ColumnDeclaration y (children 1)
    DataType UInt64
 Storage definition (children 2)
  Function MergeTree
  Function tuple (children 1)
   ExpressionList (children 2)
    Identifier x
    Identifier y