It is my understanding that the service packs/upgrades have the potential to modify all databases on the SQL Server instance, therefore, simply replacing the resource database to rollback an SP/update is not enough.
The reasoning behind this is that if we take a backup of a database on let's say SQL Server 2008 SP1, we cannot restore it in SQL Server 2008 RTM.
Please correct me if wrong.
Thanks & Regards,
Nakul Vachhrajani.
http://nakulvachhrajani.com
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