SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 2)
   ExpressionList (children 1)
    Function plus (alias y) (children 1)
     ExpressionList (children 2)
      Literal UInt64_1
      Literal UInt64_2 (alias x)
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      TableIdentifier system.one
