QUESTION NO: 60
View the Exhibit and examine the structure of the CUSTOMERS and CUST_HISTORY tables.
The CUSTOMERS table contains the current location of all currently active customers. The
CUST_HISTORY table stores historical details relating to any changes in the location of all current
as well as previous customers who are no longer active with the company.
You need to find those customers who have never changed their address.
Which SET operator would you use to get the required output?
A. INTERSECT
B. UNION ALL
C. MINUS
D. UNION
Answer: C(CUSTOMERS 中 减去改变过地址的CUST_HISTORY 的客户)
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转载于:http://blog.itpub.net/29876893/viewspace-1632412/
本文探讨了如何通过SQL查询技术,从当前客户表和历史客户变更记录表中筛选出那些从未更改过地址的活跃客户。
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