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Restore a database with multiple differential sets

sir-rob asked
Hi Experts, I had to restore a database from a while ago that had a full backup and several differentials (which is taken every day).

I thought when restoring a full and several DIFFs, all you had to do was to restore the FULL and the latest DIFF, but for some reason the server keps checking all the DIFFs (the ones between the FULL and the latest DIFF)

Does anyone know why that is? I am sure there must be a reason for the engine to pick all the DIFFs, NO?

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You have to restore your FULL database WITH NO RECOVERY option first and then you need to restore ONLY THE LAST differential backup WITH RECOVERY option if you don't have to restore transaction logs as well.

If your backups were performed without issues that is what you should do and you should have no problems. Each differential backup contains all the changes from the LAST full backup performed so it will have the changes form any previous differential backups included. That is why you need only the last one..
Scott PletcherSenior DBA
Most Valuable Expert 2018
Distinguished Expert 2019

You are right, you only need the last one.

>> I am sure there must be a reason for the engine to pick all the DIFFs, NO? <<

I think it's just that its "logic" is not that sophisticated; it doesn't really "understand" what's going on, of course.