NULLIF Function

In Oracle/PLSQL, the NULLIF function compares expr1 and expr2. If expr1 and expr2 are equal, the NULLIF function returns NULL. Otherwise, it returns expr1.

Syntax

The syntax for the NULLIF function is:

NULLIF( expr1, expr2 )

expr1 and expr2 must be either numeric values or values that are of the same datatype.

Note

expr1 can be an expression that evaluates to NULL, but it can not be the literal NULL.

Applies To

• Oracle 11g, Oracle 10g, Oracle 9i

For Example

NULLIF(12, 12)	would return NULL
NULLIF(12, 13)	would return 12
NULLIF('apples', 'apples')	would return NULL
NULLIF('apples', 'oranges')	would return 'apples'
NULLIF(NULL, 12)	would return an ORA-00932 error because expr1 can not be the literal NULL