You work as a database administrator at ABC.com. You study the exhibit carefully.
Exhibit:
You issue the following SQL statement:
Which statement is true regarding the execution of the above query?
A.
It produces an error because the AMT_SPENT column contains a null value.
B.
It displays a bonus of 1000 for all customers whose AMT_SPENT is less than CREDIT_LIMIT.
C.
It displays a bonus of 1000 for all customers whose AMT_SPENT equals CREDIT_LIMIT, or AMT_SPENT
is null.
D.
It produces an error because the TO_NUMBER function must be used to convert the result of the NULLIF
function before it can be used by the NVL2 function.
Explanation:
The NULLIF Function
The NULLIF function tests two terms for equality. If they are equal the function returns a null,
else it returns the first of the two terms tested.
The NULLIF function takes two mandatory parameters of any data type. The syntax is
NULLIF(ifunequal, comparison_term), where the parameters ifunequal and
comparison_term are compared. If they are identical, then NULL is returned. If they differ, the
ifunequal parameter is returned.