SQL Server - Check for Leap Year (Part 1)

I have this co-worker who is obsessed about leap year.  This post is dedicated to him.

There are various ways to determine if a given year is a leap year.  The first function here is using the various SQL Date functions to get the job done.

-------------------------------------------------
-- Does the function already exist? 
-- if so... drop it.
-------------------------------------------------

IF OBJECT_ID( N'dbo.xIsLeapYear',N'FN' ) IS NOT NULL
BEGIN
    print 'Function found... Dropping'
    DROP FUNCTION dbo.xIsLeapYear
END

GO

CREATE FUNCTION xIsLeapYear(@Year SmallInt)
RETURNS CHAR(3)
AS

-------------------------------------------------
--Function will Check to See if the year
--passed in is a leap year.
--
--This function uses SQL Server Date functions
--to get the job done. 
--
--You pass in a Year and it returns 'Yes' or 'No'
-------------------------------------------------
BEGIN
    DECLARE @Date   DateTime
    DECLARE @Result Char(3)
   

    -- Turn the Passed in year to Feb 28th
    SET @Date  = Convert( Varchar(4), @Year ) + '0228'
   
    -- Add one Day to the date
    SET @Date  = DateAdd( d, 1, @Date )
   
    -- Is the @date variable still February?
    IF ( DatePart(M, @date) = 2 )
        BEGIN
            SET @Result = 'Yes'
        END
    ELSE
        BEGIN
            SET @Result = 'NO'
        END


    RETURN @Result
END

GO

-------------------------------------------------
--Now we will check to see if the code works
-------------------------------------------------
PRINT ''
PRINT 'Using SQL Server Date functions to check Year.'
PRINT '----------------------------------------------'
PRINT 'Is 1900 a Leap year?  ' + dbo.xIsLeapYear(1900)
PRINT 'Is 2000 a Leap year?  ' + dbo.xIsLeapYear(2000)
PRINT 'Is 2008 a Leap year?  ' + dbo.xIsLeapYear(2008)
PRINT 'Is 2010 a Leap year?  ' + dbo.xIsLeapYear(2010)