ocp 11g考試題庫詳解：1Z0-051-090題，完整題庫請點擊這里聯(lián)系老師咨詢了解

90. Examine the structure and data in the PRICE_LIST table:

name Null Type

PROD_ID NOT NULL NUMBER(3)

PROD_PRICE VARCHAR2(10)

PROD_ID PROD_PRICE

100 $234.55

101 $6,509.75

102 $1,234

You plan to give a discount of 25% on the product price and need to display the discount amount in the same format as the PROD_PRICE.

Which SQL statement would give the required result?

A. SELECT TO_CHAR(prod_price* .25,'$99,999.99')

FROM PRICE_LIST;

B. SELECT TO_CHAR(TO_NUMBER(prod_price)* .25,'$99,999.00')

FROM PRICE_LIST;

C. SELECT TO_CHAR(TO_NUMBER(prod_price,'$99,999.99')* .25,'$99,999.00')

FROM PRICE_LIST;

D. SELECT TO_NUMBER(TO_NUMBER(prod_price,'$99,999.99')* .25,'$99,999.00')

FROM PRICE_LIST;

Answer: C

試題解析：

A，prod_price為字符，不能*.25

B，TO_NUMBER(prod_price)里面需要轉(zhuǎn)換格式

C 正確

D，本來(TO_NUMBER(prod_price,'$99,999.99')* .25已經(jīng)是數(shù)值型，就不用再TO_NUMBER轉(zhuǎn)換一回了。