On Jun 14, 8:26 am, Andy <a...@med-associates.com> wrote:
> Hi,
>
> I have a database, recovery model full.
>
> I have a maintenance plan that does a full backup everyday at 6:00
> PM. I also have another plan that does only transaction log backups
> every hour during business hours.
>
> My question is, when is it safe to delete the old logs? Never? After
> the full backup? I think it would be safe to delete logs older than
> the last full backup, but I want to be sure.
>
> Thanks
> Andy

On Jun 14, 2:27 pm, RoadRaat <jaip...@lasalleshoot.com> wrote:
> On Jun 14, 8:26 am, Andy <a...@med-associates.com> wrote:
>
> > Hi,
>
> > I have a database, recovery model full.
>
> > I have a maintenance plan that does a full backup everyday at 6:00
> > PM. I also have another plan that does only transaction log backups
> > every hour during business hours.
>
> > My question is, when is it safe to delete the old logs? Never? After
> > the full backup? I think it would be safe to delete logs older than
> > the last full backup, but I want to be sure.
>
> > Thanks
> > Andy
>
> I'll take a stab at this one. I think you might be confusing the
> transaction log with SQL Server logs located under the Management node
> in Enterprise Manager.
>
> Transaction log. This is a system file. You never delete it. It is not
> a user-readable file. It interacts with the data file. There are no
> successive generations of transaction logs. There is just one (or as
> many as you have defined as administrator). The simple description is
> that through this file the database is able to roll back transactions
> that you don't want to commit.
>
> SQL Server log (under Management node). This is an event log. You can
> read it and see database events. I think you can configure how long
> you want those logs to be retained, but I don't know exactly how.
> Suffice to say that even in this case, you still don't need to
> administer the physical files by hand yourself.
>
> RoadRaat

On Jun 14, 2:45 pm, RoadRaat <jaip...@lasalleshoot.com> wrote:
> Bet I misread your post. You asked when it is safe to delete your old
> logs. Maybe you meant your old transaction log backups.

> The question of when you can delete ANY backup depends on what point
> in time you want to be able to recover to.
>
> 1. You can always restore your last full backup.
> 2. Then you can always restore the latest subsequent differential
> backup.
> 3. Then you can restore any number of subsequent transaction log
> backups, SO LONG as the chain is complete.
> 4. Now, if you take another full backup, yes you could delete all of
> those other backup files, but then you would not be able to go back
> and restore to any of those prior points in time if you ever needed
> to. You have to figure out whether or not you care.