Re: Hot Backup Question

Sybrand,

The original poster didn't make things very clear by including the statement "I have a tablespace with 6 tablespaces", but I think if you re-phrase that to read "I have a tablespace with 6 datafiles", your answer might be slightly different.

I'm also utterly gobsmacked that a crash during hot backup resulted in you performing any recovery at all. A simple 'alter database datafile X end backup' repeated ad nauseam for all affected datafiles will mean that precisely zero recovery is actually required.

Regards
HJR <sybrandb_at_my-deja.com> wrote in message news:95loal$9rt$1_at_nnrp1.deja.com...
> In article <95kq8v$klu$1_at_nnrp1.deja.com>,
> humorous_at_my-deja.com wrote:
> > Hey gurus
> > I have a question. I have a tablespace with 6 tablespaces. They are
> > being backed up inthe
> > following way .
> > alter tablespace tablespace name begin backup;
> > cp filenum1 to filenum1.back
> > alter tablespace tablespace name end backup;
> >
> > alter tablespace tablespace name begin backup;
> > cp filenum1 to filenum2.back
> > alter tablespace tablespace name end backup;
> >
> > alter tablespace tablespace name begin backup;
> > cp filenum1 to filenum3.back
> > alter tablespace tablespace name end backup;
> >
> > alter tablespace tablespace name begin backup;
> > cp filenum1 to filenum4.back
> > alter tablespace tablespace name end backup;
> >
> > alter tablespace tablespace name begin backup;
> > cp filenum1 to filenum5a.back
> > alter tablespace tablespace name end backup;
> >
> > Can this be a problem in the backups being consistent ?
> > Do y'all see any problem with this ?
> >
> > Or should I go for the
> >
> > alter tablespace tablespacename begin backup;
> > cp filenum1 to filenum1.bak
> > cp filenum2 to filenum2.bak
> > cp filenum3 to filenum3.bak
> > cp filenum4 to filenum4.bak
> > cp filenum5 to filenum5.bak
> >
> > alter tablespace tablespacename end backup;
> >
> > Is this a more preferred option ? If so why ?
> >
> > Sent via Deja.com
> > http://www.deja.com/
> >
> Scenario 1 is the preferred option. Scenario 2 is not preferred as it
> places *all* tablespaces in backup mode at the same time. Thus, it will
> definitely generate much more redo than in the first scenario.
> Also, if the database crashes during hot backup (which happened to me
> once) you will be forced to recover the *complete* database, as all
> tablespaces are marked as inconsistent.
>
> Hth,
> --
> Sybrand Bakker, Oracle DBA
>
> All standard disclaimers apply
> ------------------------------------------------------------------------
>
>
> Sent via Deja.com
> http://www.deja.com/
Received on Mon Feb 05 2001 - 02:56:35 CST