Re: Hot Backup Question

It makes precious little difference to the ability to restore which way you do it, to be honest. The only thing the "begin backup" command does is to lock the headers of the datafiles of the tablespace concerned so that we can guarantee that we know the earliest point from which application of Redo should proceed.

Doing it the first way might mean that the recovery of datafile 6 would require less redo to be applied (since its header would be copied at a higher SCN than file 1). You also give yourself the flexibility to copy file 1 on Monday, and file 6 on Saturday. Provided you keep all the archives since Monday, all recovery options would remain open.

Doing it your second way would imply that all the datafiles would have to be copied in rapid succession (because you really don't want to be in hot backup mode for too long because of the block-sized Redo generated for that tablespace whilst in that state).

Horses for courses, I'd say.

Regards
HJR <humorous_at_my-deja.com> wrote in message news:95kq8v$klu$1_at_nnrp1.deja.com...
> 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 th

 is ?
> >
> 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/
Received on Sun Feb 04 2001 - 23:33:07 CST