SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 3)
   ExpressionList (children 1)
    Function plus (children 1)
     ExpressionList (children 2)
      Literal UInt64_2
      Literal UInt64_1
   TablesInSelectQuery (children 2)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      TableIdentifier system.one (alias X)
    TablesInSelectQueryElement (children 2)
     TableExpression (children 1)
      TableIdentifier system.one (alias Y)
     TableJoin (children 1)
      Function equals (children 1)
       ExpressionList (children 2)
        Function plus (children 1)
         ExpressionList (children 2)
          Identifier X.dummy
          Literal UInt64_1
        Identifier Y.dummy
   Set