Joannes Vermorel Joannes Vermorel - 5 months ago 22
SQL Question

Boolean 'NOT' in T-SQL not working on 'bit' datatype?

Trying to perform a single boolean NOT operation, it appears that under MS SQL Server 2005, the following block does not work

DECLARE @MyBoolean bit;
SET @MyBoolean = 0;
SET @MyBoolean = NOT @MyBoolean;
SELECT @MyBoolean;

Instead, I am getting more successful with

DECLARE @MyBoolean bit;
SET @MyBoolean = 0;
SET @MyBoolean = 1 - @MyBoolean;
SELECT @MyBoolean;

Yet, this looks a bit a twisted way to express something as simple as a negation.

Am I missing something?


Use the ~ operator:

DECLARE @MyBoolean bit
SET @MyBoolean = 0
SET @MyBoolean = ~@MyBoolean
SELECT @MyBoolean