Term: NULLIF

Definition:
The Oracle NULLIF function is a null handling function which accepts two numeric arguments. If both of the arguments are equal it returns NULL; otherwise it returns the first argument. It is most commonly used for handling the ZERO_DIVIDE exception.

Example Syntax:

NULLIF(arg1, arg2)

where arg1 and arg2 are of the NUMBER datatype.

Example Usage:

The SQL example below raises a ZERO_DIVIDE exception as it foolishly tries to divide a number by zero.

SQL> SELECT 12/0 FROM DUAL;

select 12/0 from dual

         *

ERROR at line 1:

ORA-01476: divisor is equal to zero

The SQL example below handles the exception raised above by using the NULLIF function in the Divisor.

SQL> SELECT 12/NULLIF(0,0) FROM DUAL;



12/NULLIF(0,0)

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