OCP 1Z0 051 V9 02 124题

分享一下我老师大神的人工智能教程！零基础，通俗易懂！http://blog.youkuaiyun.com/jiangjunshow

也欢迎大家转载本篇文章。分享知识，造福人民，实现我们中华民族伟大复兴！

               

124. View the Exhibit and examine the structure of the PROMOTIONS, SALES, and CUSTOMER tables.

You need to generate a report showing the promo name along with the customer name for all products

that were sold during their promo campaign and before 30th October 2007.

You issue the following query:

SQL> SELECT promo_name,cust_name       

FROM promotions p JOIN sales s          

ON(time_id BETWEEN promo_begin_date AND promo_end_date)         

JOIN customer c         

ON (s.cust_id = c.cust_id) AND time_id < '30-oct-2007';

Which statement is true regarding the above query? 

 

A. It executes successfully and gives the required result.

B. It executes successfully but does not give the required result.

C. It produces an error because the join order of the tables is incorrect.

D. It produces an error because equijoin and nonequijoin conditions cannot be used in the same SELECT

statement.

Answer: B

答案解析：

参考：http://blog.youkuaiyun.com/rlhua/article/details/12877591

题意要求：需要一个报表，显示所有产品的promo name和customer name，销售的产品是在promo campaign之内，并且在2007年10月30日以前

 缺少条件， promotions p JOIN sales s  之间应该有个PROMO_ID的等值连接，才能得出正确结果。

           

给我老师的人工智能教程打call！http://blog.youkuaiyun.com/jiangjunshow