（55）Evaluate the following two queries:

SELECT cust_last_name, cust_city

FROM customers

WHERE cust_credit_limit IN (1000, 2000, 3000);

SELECT cust_last_name, cust_city

FROM customers

WHERE cust_credit_limit = 1000 OR cust_credit_limit = 2000 OR cust_credit_limit = 3000;

Which statement is true regarding the above two queries?

A. Performance would improve in query 2.

B. Performance would degrade in query 2.

C. There would be no change in performance.

D. Performance would improve in query 2 only if there are null values in the CUST_CREDIT_LIMIT column.

答案：（C）

解析：

C，因为这2个语句是等价的

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OCP 1Z0-051-55