BizTalk Server 2004 "BizTalkDTADB" clean script

Around client we happen this problem. It became larger too.
We must create job schedule this script

I have been ever see "BizTalkDTADB" size is 60GB before.

This is a default istallation sdk directory.
C:\Program Files\Microsoft BizTalk Server 2004\SDK\Samples\Admin\Database Maintenance\Purge_DTADB.sql

DECLARE @Today datetime
SET @Today = GETDATE() - 30
EXEC dtasp_PruneTrackingDatabase @Today

If you want Tracking Log count, run the following:

select datepart(year,dtTimeStamp), datepart(month,dtTimeStamp), count(*) as 'rowcount' from dta_DebugTrace group by datepart(year,dtTimeStamp), datepart(month,dtTimeStamp)order by datepart(year,dtTimeStamp), datepart(month,dtTimeStamp)

To clean up this database, it is suggested you run the following:

select * from dta_DebugTracewhere dtTimeStamp < '2006-01-01'
But this script is running very long time 20hours more
I found reference link.
http://support.microsoft.com/?id=894253