DIFFERENTIAL backup

Thread view:

Enable EMail Alerts

Start New Thread

Thread rating:

Ben Rum - 31 Mar 2007 09:22 GMT

Just want to clarify the date from which a DB backup with DIFFERENTIAL
option includes its changes.

I have a db which I do a full backup on Saturday, and a differential the
other days (this is plenty in our case)

If someone performs an ad-hoc backup for whatever reason during the
week, say prior to a roll-out, I assume the DIFFERENTIAL backup that
night will only include changes back to the ad-hoc backup? Can I force
it to go back to the Saturday one at all?

Reply to this Message

Tibor Karaszi - 31 Mar 2007 10:04 GMT

> If someone performs an ad-hoc backup for whatever reason during the week, say prior to a roll-out,
> I assume the DIFFERENTIAL backup that night will only include changes back to the ad-hoc backup?

Yes, assuming that the ad-hoc backup was a full database backup.

> Can I force it to go back to the Saturday one at all?

No. However the ad-hoc backup should have been taken using the COPY_ONLY clause (new in 2005). That
will not break the backup sequence for diff backups.

Signature

Tibor Karaszi, SQL Server MVP
http://www.karaszi.com/sqlserver/default.asp
http://sqlblog.com/blogs/tibor_karaszi

> Just want to clarify the date from which a DB backup with DIFFERENTIAL option includes its
> changes.
[quoted text clipped - 5 lines]
> I assume the DIFFERENTIAL backup that night will only include changes back to the ad-hoc backup?
> Can I force it to go back to the Saturday one at all?

Reply to this Message