SQL Purge old database backups

/*
This script works with SQL 2005 to remove old backups from a file location
xp_delete_file
is the key to this operation. This is an undocumented SQL server function.
It deletes all file older than the date given in the parameter.
I use this to implement 24 hour disk to disk backup

The TSQL assumes the full backups have an extension of BAK and transaction logs
have an extension of TRN. It will purge both transaction logs and full backups
*/

USE [master]
GO

DECLARE @tDatabases TABLE
( databaseId int
--, DATABASE_NAME varchar(25)
)

INSERT INTO @tDatabases ( databaseId )
SELECT DISTINCT s_mf.database_id
from sys.master_files s_mf
where s_mf.state = 0 -- ONLINE
AND has_dbaccess(db_name(s_mf.database_id)) = 1 -- Only look at databases to which we have access
AND s_mf.database_id <> 2 --eliminate temp db



DECLARE @dbId int;
Declare @DateToDelete datetime;
declare @DateString char(8);
DECLARE @filePath nvarchar(max);

SET @DateToDelete=DateAdd(day,-1,GetDate()); --The -1 in the date diff is 24 hours
set @DateString = Convert(nvarchar(30),@DateToDelete,1)+' '+ Convert(nvarchar(30),@DateToDelete,8); --Set up SQL string


SET @filePath = '\server_backup_directory' ;

DECLARE cursor_usage CURSOR FOR
SELECT databaseId FROM @tDatabases;

OPEN cursor_usage;

FETCH NEXT FROM cursor_usage INTO @dbId;
WHILE @@FETCH_STATUS = 0
BEGIN
PRINT db_name(@dbId);
DECLARE @execString nvarchar(max)
--Remove full backups
SET @execString = 'master.dbo.xp_delete_file 0, N''' + @filePath + db_name(@dbId) + '''' +',N''bak'' ,' + '''' + @DateString + ''''
PRINT @execString;
EXECUTE (@execString);
--Remove transaction logs
SET @execString = 'master.dbo.xp_delete_file 0, N''' + @filePath + db_name(@dbId) + '''' +',N''trn'' ,' + '''' + @DateString + ''''
PRINT @execString;
EXECUTE (@execString);

FETCH NEXT FROM cursor_usage INTO @dbId;
END;
CLOSE cursor_usage;
DEALLOCATE cursor_usage;