ocp 11g认证题库大全:1Z0-051-116题
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ocp 11g认证题库大全:1Z0-051-116题,完整题库请点击这里联系老师咨询了解
116. Examine the data in the ORD_ITEMS table:
ORD_NO ITEM_NO QTY
1 111 10
1 222 20
1 333 30
2 333 30
2 444 40
3 111 40
You want to find out if there is any item in the table for which the average maximum quantity is more than
50.
You issue the following query:
SQL> SELECT AVG(MAX(qty))
FROM ord_items
GROUP BY item_no
HAVING AVG(MAX(qty))>50;
Which statement is true regarding the outcome of this query?
A. It executes successfully and gives the correct output.
B. It gives an error because the HAVING clause is not valid.
C. It executes successfully but does not give the correct output.
D. It gives an error because the GROUP BY expression is not valid.
Answer: B
试题解析:
HAVING子句后面不能有好几个组函数嵌套,只能使用一个组函数。
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