我正在阅读工作中的一些旧代码，并注意到有几个视图具有order by 1子句。这有什么作用呢?

例子:

Create view v_payment_summary AS
SELECT A.PAYMENT_DATE,
       (SELECT SUM(paymentamount)
          FROM payment B
         WHERE PAYMENT_DATE = B.PAYMENT_DATE
           and SOME CONDITION) AS SUM_X,
       (SELECT SUM(paymentamount)
          FROM payment B
         WHERE PAYMENT_DATE = B.PAYMENT_DATE
           and SOME OTHER CONDITION) AS SUM_Y    
FROM payment A    
ORDER BY 1;