[From SQLServer Magazine
Microsoft released SQL Server 2000 Service Pack 3 (SP3) on January 17, raising the inevitable question, "To install or not to install?" SQL Server Product Support Services (PSS) recommends applying the latest service pack even if you're not aware of a specific fix that will help you. I'm aggressive about applying service packs because I hate to spend hours tracking down a problem only to find that the last service pack fixed it. However, some DBAs prefer to wait a few weeks and monitor the newsgroups to be sure that installing a new service pack won't create a problem. And some SQL Server shops that have high uptime requirements for their production systems might have to wait months before applying a service pack. A recent newsgroup posting said that one company took 8 months to test and deploy SP2 on one of its critical systems.
The "don't fix it if it ain't broke" school of thought is prudent when it comes to server maintenance. SQL Server service packs are especially tricky because you can't easily remove them. To remove SP3 (like SP1 and SP2), you have to uninstall SQL Server, then reinstall from the ground up. Needless to say, you should have a well-crafted recovery plan--including tested backups--before you apply a service pack to a production server. Like doctors, good system administrators should live by the creed "first do no harm" when making decisions that can affect the stability or availability of the systems they manage.
However, once you've installed SP3, you can take advantage of the upgrades it provides. Service packs are supposed to fix bugs, but SQL Server service packs also regularly add new...
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