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"frank" <fbortel_at_home.nl> wrote in message news:39F0915F.B8FE219D_at_home.nl...
>
> Syltrem wrote:
>
> > Hello!
> >
> > I was following this conversation and it raised a question:
> >
> > If I always do online backups (never offline), how do I restore my
entire
> > database (let's say the whole place blew up)?
> >
> > Specifically:
> > Do I need to restore my redo log files from tape, or will the ALTER
DATABASE
> > OPEN RESETLOGS create them?
>
> Of course you need them from tape, where else from? You just
> blew up your production server!
>
> >
> > Do I need to recreate the controlfile from a script (create controlfile
> > reuse...)
>
> reuse *what*?
>
> > or should I use the actual controlfiles that I saved to tape
> > during the backup?
>
> Interesting one: could it depend on time of the backup?
> I.e. if you backed up your control files last, you would
> do a recover database, if your datafile(s) are more recent, you
> would do recover using backup controlfile.
> Comments (Howard, Niall, Sybrand,...), please?
>
Hi Frank... The time of backup is irrelevant, because you have to include the keywords 'using backup controlfile' as part of the process, and that instructs SMON not to rely on the SCN in the Control File as the timestamp to which the rest of the database should synchronise. So it doesn't particularly matter one way or another as far as I can work out -myself, I'd still use the trace file script, suitably modified for the fact that the lack of Redo Logs means it can't successfully complete the recover and open commands it usually contains.
Regards
HJR
> >
> >
> > Thanks!
> >
> > "Howard J. Rogers" <howardjr_at_www.com> wrote in message
> > news:39f057ef$1_at_news.iprimus.com.au...
> > > Yes, don't restore the Control Files or online Redo Logs.
> > >
> > > If you restore everything from a cold backup, you have a perfectly
> > > synchronised database as at the time of the cold backup.
> > >
> > > What prompts the application of Archives is when SMON spots that the
> > > timestamps on the Control Files don't agree with the timestamps on
> > > everything else. So make sure you leave the Control Files at the
point in
> > > time in the future, and bring back only the 'old' datafiles. The same
goes
> > > for the Redo Logs (since you'll need their content to bring the
database
> > > bang up to date -overwrite them with last night's backup, and you've
just
> > > lost data).
> > >
> > > The rules of backup and recovery are really very simple -and the
simplest
of
> > > them all is, if you have archives, you only ever restore the files
which
are
> > > causing the problem, not the whole lot.
> > >
> > > Regards
> > > HJR
> > > --
> >