View the Exhibit and examine the structure of the CUSTOMERS table.
Using the CUSTOMERS table,you need to generate a report that shows the average credit limit for customers in WASHINGTON and NEW YORK.
Which sql statement would produce the required result?
A. SELECT cust_city,AVG(cust_credit_limit)
FROM customers
WHERE cust_city IN ('WASHINGTON','NEW YORK')
GROUP BY cust_credit_limit,cust_city;
B. SELECT cust_city,'NEW YORK')
GROUP BY cust_city,cust_credit_limit;
C. SELECT cust_city,'NEW YORK')
GROUP BY cust_city;
D. SELECT cust_city,AVG(NVL(cust_credit_limit,0))
FROM customers
WHERE cust_city IN ('WASHINGTON','NEW YORK');
答案：C
Using the CUSTOMERS table,you need to generate a report that shows the average credit limit for customers in WASHINGTON and NEW YORK.
Which sql statement would produce the required result?
A. SELECT cust_city,AVG(cust_credit_limit)
FROM customers
WHERE cust_city IN ('WASHINGTON','NEW YORK')
GROUP BY cust_credit_limit,cust_city;
B. SELECT cust_city,'NEW YORK')
GROUP BY cust_city,cust_credit_limit;
C. SELECT cust_city,'NEW YORK')
GROUP BY cust_city;
D. SELECT cust_city,AVG(NVL(cust_credit_limit,0))
FROM customers
WHERE cust_city IN ('WASHINGTON','NEW YORK');
答案：C
二、题目翻译
三、题目解析
AB选项不正确，因为GROUP BY里的分组的列不对，这里应该按cust_city分组。 D选项不正确，因为要根据城市求平均值，所以需要使用GROUP BY子句分组。
