Click here to view and discuss this page in DocCommentXchange. In the future, you will be sent there automatically.

SQL Anywhere 10.0.1 » SQL Anywhere Server - SQL Reference » SQL Functions » Alphabetical list of functions

NOW function [Date and time] Next Page

NULLIF function [Miscellaneous]

Provides an abbreviated CASE expression by comparing expressions.


NULLIF( expression-1, expression-2 )


expression-1    An expression to be compared.

expression-2    An expression to be compared.


NULLIF compares the values of the two expressions.

If the first expression equals the second expression, NULLIF returns NULL.

If the first expression does not equal the second expression, or if the second expression is NULL, NULLIF returns the first expression.

The NULLIF function provides a short way to write some CASE expressions.

See also
Standards and compatibility

The following statement returns the value a:

SELECT NULLIF( 'a', 'b' );

The following statement returns NULL.

SELECT NULLIF( 'a', 'a' );