Boolean Testing Operators

Description

This operator is used exclusively to check for TRUE, FALSE, or NULL. For an introduction to NULL, please refer to the "Nulls" section.

Operator Introduction

Operator	Function	Example
x IS [NOT] TRUE	Checks if x is TRUE. Returns TRUE if x is TRUE, otherwise returns FALSE.	SELECT 1 IS NOT TRUE
x IS [NOT] FALSE	Checks if x is FALSE. Returns TRUE if x is FALSE, otherwise returns FALSE.	SELECT 1 IS NOT FALSE
x IS [NOT] NULL	Checks if x is NULL. Returns TRUE if x is NULL, otherwise returns FALSE.	SELECT 1 IS NOT NULL