Jeff Moden (2/16/2009)
How much of this applies to the system's databases (not including TempDB, of course)?
MSDB can be repaired, I believe (haven't tried it). Master I would recommend restore or rebuild, though I have seen someone repair it successfully. Model, since it should have nothing in it, you should be able to copy from another server.
Depends what the corruption is. If it's just in the nonclusters, then repair's probably safe even in the system databases. If it's in the clustered index then my recommendation would be restore or rebuild (especially with master)
Master and msdb can be completely recreated, by the rebuild master function of the installer (master) or by script (msdb). It won't get any data back, but it will get the DB usable and free of corruption.
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