66、(22-19)choose two

Examine the structure proposed for the TRANSACTIONS table:

Which two statements are true regarding the creation and storage of data in the above table structure?

A) The TRANS_DATE column would be able to store day, month, century, year, hour, minutes, seconds,

and fractions of seconds.

B) The CUST_STATUS column would store exactly one character.

C) The TRANS_VALIDITY column would have a maximum size of one character.

D) The TRANS_VALIDITY column would give an error.

E) The CUST_STATUS column would give an error.

F) The CUST_CREDIT LIMIT column would not be able to store decimal values.


(解析:定义列的数据类型时,char 的可以省略位数,默认是 1,但是 varchar2 不能省略位数,否则报错。

注意 date 和 timestamp 的格式区别:

date 类型存储数据的格式为年月日时分秒,可以精确到秒

timestamp 类型存储数据的格式为年月日时分秒,可以精确到纳秒(9 位)