ocp 11g考試題庫(kù)詳解：1Z0-051-114題，完整題庫(kù)請(qǐng)點(diǎn)擊這里聯(lián)系老師咨詢了解

114. View the Exhibit and examine the structure of the SALES table.

The following query is written to retrieve all those product ID s from the SALES table that have more than

55000 sold and have been ordered more than 10 times.

SQL> SELECT prod_id

FROM sales

WHERE quantity_sold > 55000 AND COUNT(*)>10

GROUP BY prod_id

HAVING COUNT(*)>10;

Which statement is true regarding this SQL statement?

A. It executes successfully and generates the required result.

B. It produces an error because COUNT(*) should be specified in the SELECT clause also.

C. It produces an error because COUNT(*) should be only in the HAVING clause and not in the WHERE clause.

D. It executes successfully but produces no result because COUNT(prod_id) should be used instead of COUNT(*).

Answer: C

試題解析：

因?yàn)镃OUNT(*)只能用在HAVING子句中，不能在WHERE子句中

where子句不能帶組函數(shù)