CREATE PROCEDURE [LoneUser]
--INPUT
@DBName nvarchar(50),
@UserName nvarchar(50)
AS
Exec sp_configure 'allow updates','1'
RECONFIGURE WITH OVERRIDE

Declare @ExecStr nvarchar(4000)

Select @ExecStr = ' Declare @b varbinary(85) '
+ ' Use Master'
+ ' Select @b = sid From syslogins Where Name = ''' + @UserName + ''''
+ ' Use ' + @DBName
+ ' Update sysusers Set sid = @b Where name = ''' + @UserName + ''''

--Print @ExecStr
Exec(@ExecStr)

Exec sp_configure 'allow updates','0'
RECONFIGURE WITH OVERRIDE