Fastest way to determine if record exists

Question

As the title suggests... I\'m trying to figure out the fastest way with the least overhead to determine if a record exists in a table or not.

Sample query:

Answer 1

SELECT CASE WHEN EXISTS (SELECT TOP 1 *
                         FROM dbo.[YourTable] 
                         WHERE [YourColumn] = [YourValue]) 
            THEN CAST (1 AS BIT) 
            ELSE CAST (0 AS BIT) END

This approach returns a boolean for you.