IF exists (SELECT * from dbo.sysobjects 
	WHERE id = object_id(N'dbo.sp_MyProc') 
		and OBJECTPROPERTY(id, N'IsProcedure') = 1)

>USE SC
>GO
>
>IF EXISTS(SELECT * FROM SysObjects WHERE Id = "sp_MyProc")
>	DROP PROCEDURE sp_MyProc
>
>GO
>
>CREATE PROC sp_MyProc....
>
>