There was a similar thread on this earlier, but my question is specific to upgrading from SQL2005 to 2008: when upgrading in-place is not possible because the machine has to be re-imaged, which method is preferrable - detaching and re-attaching the db files, or backup/restore?
Detach/attach is obviously faster and accoding to msdn possible, but I wonder if anyone could share real life experiences?
Thanks Max
Backup/restore would be the recommended method.
Reason being, if something goes wrong you always have the unaltered original (and a copy of the backup if you had the foresight) that you can go back to. You don't have that option if you use detach/attach.
how much down-time is allowed for your cut-over:
How big are the databases that need to be copied?
backup/restore + logshipping may be the fastest way to do a cut-over if time is critical. With either detach/attach or backup/restore the longest part is waiting for the file copy to finish.