Monthly Calendar in SQL Server

IF OBJECT_ID('SQL_Calendar','P') IS NOT NULL
DROP PROC SQL_Calendar
GO
CREATE PROC	SQL_Calendar
	(
	@Month	INT	=	NULL	,
	@Year	INT	=	NULL
	)AS
/********************************************************/
/*	Created By	: Pandian S		*/
/*	Created On: 01-Oct-2009, Thursday	*/
/*	Purpose	: Month Calendar		*/
/*	How to	: EXEC SQL_Calendar <MONTH>,<YEAR>*/
/*		: EXEC SQL_Calendar 10,2009	*/
/********************************************************/
BEGIN
	SET NOCOUNT ON

	DECLARE @Serial	INT			,
			@Days	INT			,
			@Starts	INT			,
			@Concat	VARCHAR(100),
			@ActDate	DATETIME,
			@Date	VARCHAR(11)	
	
	IF (@Month IS NULL AND @Year IS NULL)
	BEGIN
		SELECT	@Month	=	MONTH(GETDATE())
		SELECT	@Year	=	YEAR(GETDATE())
	END
	
	IF (@Month IS NULL AND @Year IS NOT NULL)
		SELECT	@Month	=	MONTH(GETDATE())

	IF (@Month IS NOT NULL AND @Year IS NULL)
		SELECT	@Year	=	YEAR(GETDATE())

	IF (@Month <=0 OR @Month >12) RETURN

	IF (@Year <= 1752)
	BEGIN
		PRINT 'Year Out-of-Range'
		RETURN	 
	END

	IF (@Year = 9999 AND @Month>11)
	BEGIN
		PRINT 'Date Out-of-Range'
		RETURN	 
	END

	SELECT	@Starts	=	CASE DATENAME(DW,CAST(@Year AS VARCHAR) + '-' + CAST(@Month AS VARCHAR) + '-01') WHEN 'Sunday' THEN 0 WHEN 'Monday' THEN 1 WHEN 'Tuesday' THEN 2 WHEN 'Wednesday' THEN 3 WHEN 'Thursday' THEN 4 WHEN 'Friday' THEN 5 WHEN 'Saturday' THEN 6 END
	SELECT	@Concat	=	''

	SELECT	@Date	= CAST(@Year AS VARCHAR)  + '-' + CAST(@Month AS VARCHAR) + '-01'
	SELECT	@Days	= DATEDIFF(DD,@DATE,DATEADD(MM,1,@DATE))

	SELECT	@Serial	=	1
	PRINT	'Calendar : ' +  DATENAME(MM,CAST(@Year AS VARCHAR) + '-' + CAST(@Month AS VARCHAR) + '-01')  + ', ' + CAST(@Year AS VARCHAR) + CHAR(10) + Replicate('-',30) + CHAR(10)
	PRINT	' S	 M	 T	 W	 T	 F	 S'
	WHILE (@Serial <= @Days)
	BEGIN
		
		SELECT	@Starts	=	CASE DATENAME(DW,CAST(@Year AS VARCHAR) + '-' + CAST(@Month AS VARCHAR) + '-' + CAST(@Serial AS VARCHAR)) WHEN 'Sunday' THEN 0 WHEN 'Monday' THEN 1 WHEN 'Tuesday' THEN 2 WHEN 'Wednesday' THEN 3 WHEN 'Thursday' THEN 4 WHEN 'Friday' THEN 5 WHEN 'Saturday' THEN 6 END
		
		IF (@Starts = 0)	
			IF (LEN(@Concat) =0)
				SELECT	@Concat	=	@Concat	+	' ' + CAST(@Serial AS VARCHAR) 
			ELSE
				SELECT	@Concat	=	@Concat	+	CHAR(13) + CASE WHEN LEN(CAST(@Serial AS VARCHAR)) = 1 THEN ' ' ELSE '' END + CAST(@Serial AS VARCHAR) 
		ELSE
			IF (LEN(@Concat) =0)
				SELECT	@Concat	=	@Concat	+	REPLICATE(CHAR(9),@Starts) + CASE WHEN LEN(CAST(@Serial AS VARCHAR)) = 1 THEN ' ' ELSE '' END + CAST(@Serial AS VARCHAR)
			ELSE
				SELECT	@Concat	=	@Concat	+	CHAR(9) + CASE WHEN LEN(CAST(@Serial AS VARCHAR)) = 1 THEN ' ' ELSE '' END + CAST(@Serial AS VARCHAR)
		
		SELECT	@Serial = @Serial + 1
	END

	PRINT @Concat + CHAR(10)
END

Calendar : October, 2009
------------------------------

 S	 M	 T	 W	 T	 F	 S
				 1	 2	 3
 4	 5	 6	 7	 8	 9	10
11	12	13	14	15	16	17
18	19	20	21	22	23	24
25	26	27	28	29	30	31