OCP-1Z0-051-2015-50题

QUESTION NO: 50

View the Exhibits and examine the structures of the PROMOTIONS and SALES tables.

Which statement is true regarding the output of the above query?
A. It gives details of product IDs that have been sold irrespective of whether they had a promo or
not
B. It gives the details of promos for which there have been no sales
C. It gives the details of promos for which there have been sales
D. It gives details of all promos irrespective（无关的，无论） of whether they have resulted in a sale or not
Answer: D

Explanation:

此处是右连接promotions ，即显示所有promotions 表中的信息，不管sales 表中promo_id 是否有。