Which SQL statement will give the required output?
A) SELECT str.name, s1.items_id, SUM(s1.quantity)
FROM sales s1 JOIN stores str
ON (s1.store_id = str.store_id)
GROUP BY str.name, s1.items_id, s1.quantity;
B) SELECT str.name, s1.items_id, SUM(s1.quantity)
FROM sales s1 JOIN stores str
ON (s1.store_id = str.store_id)
GROUP BY str.name, s1.items_id;
C) SELECT str.name, s1.items_id,
(SELECT SUM(quantitY)
FROM sales sls
ON sls.store_id = s1.store_id
GROUP BY sls.store_id)
FROM sales s1 JOIN stores str
ON (s1.store_id = str.store_id);
D) SELECT str.name, s1.items_id, SUM(s1.quantity)
FROM sales s1 JOIN stores str ON (s1.store id = str.store_id)
GROUP BY s1.items_id, s1.quantity;
Answer：B
(解析：分组函数的最基本特点，没有出现在分组函数中的列必须要出现在 group by 子句中。)
【OCP-12c】CUUG最新考试原题整理及答案（071-9）
原文：http://blog.51cto.com/13854012/2350469