ocp 11g認(rèn)證題庫詳解：1Z0-051-066題，完整題庫請(qǐng)點(diǎn)擊這里聯(lián)系老師咨詢了解

66. View the Exhibit and examine the data in the COSTS table.

You need to generate a report that displays the IDs of all products in the COSTS table whose unit price is

at least 25% more than the unit cost. The details should be displayed in the descending order of 25% of

the unit cost.

You issue the following query:

SQL>SELECT prod_id

FROM costs

WHERE unit_price >= unit_cost * 1.25

ORDER BY unit_cost * 0.25 DESC;

Which statement is true regarding the above query?

A. It executes and produces the required result.

B. It produces an error because an expression cannot be used in the ORDER BY clause.

C. It produces an error because the DESC option cannot be used with an expression in the ORDER BY

clause.

D. It produces an error because the expression in the ORDER BY clause should also be specified in the

SELECT clause.

Answer: A

試題解析：

Order by可以只用表達(dá)式來排序

order by 可以表達(dá)式sal*10

可以列別名 sal10

可以雙引號(hào) "sal10"