【2019年8月】OCP 071认证考试最新版本的考试原题-第21题

choose two

In the PROMOTIONS table, the PROMO_BEGTN_DATE columm is of datatype DATE and the default date format is DD-MON-RR.

Which two statements are true about expressions using PROMO_BEGIN_DATE contained in a queny?

A) TO_NUMBER(PROMO_ BEGIN_DATE) - 5 will return number

B) TO_DATE(PROMO_BEGIN_DATE * 5) will return a date

C) PROMO_BEGIN_DATE - SYSDATE will return a number.

D) PROMO_BEGIN_DATE - 5 will return a date.

E) PROMO_BEGIN_DATE - SYSDATE will return an error.

Answer：CD

(解析：这道题考的还比较有意义，AAnswer：错是由于日期型的不能转换为 number;日期不能乘除某个数，因此 BAnswer：错;可是日期型的是能够进行加减。)