How can I declare a Boolean parameter in SQL statement?

Question

How can I declare a Boolean parameter in SQL statement?

Answer 1

SQL Server recognizes 'TRUE' and 'FALSE' as bit values. So, use a bit data type!

declare @var bit
set @var = 'true'
print @var

That returns 1.

Answer 2

The same way you declare any other variable, just use the bit type:

DECLARE @MyVar bit
Set @MyVar = 1  /* True */
Set @MyVar = 0  /* False */

SELECT * FROM [MyTable] WHERE MyBitColumn = @MyVar