CreateQuery tbl4 (children 3)
 Identifier tbl4
 Columns definition (children 1)
  ExpressionList (children 3)
   ColumnDeclaration key (children 1)
    DataType Int
   ColumnDeclaration x (children 1)
    DataType Int
   ColumnDeclaration y (children 1)
    DataType Int
 Storage definition (children 3)
  Function MergeTree (children 1)
   ExpressionList
  Identifier key
  Set
