OCP-1Z0-051-V9 02-141題
141. View the Exhibit and examine the structure of CUSTOMERS and GRADES tables.
You need to display names and grades of customers who have the highest credit limit.
Which two SQL statements would accomplish the task? (Choose two.)
A. SELECT custname, grade
FROM customers, grades
WHERE (SELECT MAX(cust_credit_limit)
FROM customers) BETWEEN startval and endval;
B. SELECT custname, grade
FROM customers, grades
WHERE (SELECT MAX(cust_credit_limit)
FROM customers) BETWEEN startval and endval
AND cust_credit_limit BETWEEN startval AND endval;
C. SELECT custname, grade
FROM customers, grades
WHERE cust_credit_limit = (SELECT MAX(cust_credit_limit)
FROM customers)
AND cust_credit_limit BETWEEN startval AND endval;
D. SELECT custname, grade
FROM customers , grades
WHERE cust_credit_limit IN (SELECT MAX(cust_credit_limit)
FROM customers)
AND MAX(cust_credit_limit) BETWEEN startval AND endval;
Answer: BC
答案解析：
參考：http://blog.csdn.net/rlhua/article/details/12879585
題意要求顯示有最高credit limit的使用者的名稱和等級。
A，缺少 cust_credit_limit BETWEEN startval AND endval這個條件。 BC，使用的非等值連線 D有語法錯誤，WHERE子句裡不能使用組函式
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