Re: Online Backup question - Thanks

From: Jan Gelbrich <j_gelbrich_at_westfalen-blatt.de>
Date: Wed, 25 Feb 2004 09:19:00 +0100
Message-ID: <c1hlvh$1hff8g$1@ID-93924.news.uni-berlin.de>

"Richard Foote" <richard.foote_at_bigpond.com> schrieb im Newsbeitrag news:ziH_b.74332$Wa.1991_at_news-server.bigpond.net.au...
> "Jan Gelbrich" <j_gelbrich_at_westfalen-blatt.de> wrote in message
> news:c1f1g2$1gkuji$1_at_ID-93924.news.uni-berlin.de...
> > Hello,
> >
> > I would like to hear some opinions about online backup ordering.
> > Which "style" is better (safe, fast) ?
> >
> > This one ?
> >
> > I.
> >
> > ALTER TABLESPACE SYSTEM BEGIN BACKUP;
> > ALTER TABLESPACE RBS BEGIN BACKUP;
> > ALTER TABLESPACE TEMP BEGIN BACKUP;
> > ALTER TABLESPACE TOOLS BEGIN BACKUP;
> > ALTER TABLESPACE USERS BEGIN BACKUP;
> > and so on ...
> >
> > !cp /u01/oradata/ora8/system01.dbf /var/backup
> > !cp /u01/oradata/ora8/system02.dbf /var/backup
> > !cp /u01/oradata/ora8/rbs01.dbf /var/backup
> > !cp /u01/oradata/ora8/rbs02.dbf /var/backup
> > !cp /u01/oradata/ora8/temp01.dbf /var/backup
> > !cp /u01/oradata/ora8/tools01.dbf /var/backup
> > !cp /u01/oradata/ora8/users01.dbf /var/backup
> > and so on ... about 15 more dbfs follow.
> >
> > ALTER TABLESPACE SYSTEM END BACKUP;
> > ALTER TABLESPACE RBS END BACKUP;
> > ALTER TABLESPACE TEMP END BACKUP;
> > ALTER TABLESPACE TOOLS END BACKUP;
> > ALTER TABLESPACE USERS END BACKUP;
> > and so on ...
> >
> > ... or this one ?
> >
> > II.
> >
> > --Backup Setting per Tablespace
> > ALTER TABLESPACE SYSTEM BEGIN BACKUP;
> > !cp /u01/oradata/ora8/system01.dbf /var/backup
> > !cp /u01/oradata/ora8/system02.dbf /var/backup
> > ALTER TABLESPACE SYSTEM END BACKUP;
> >
> > ALTER TABLESPACE RBS BEGIN BACKUP;
> > !cp /u01/oradata/ora8/rbs01.dbf /var/backup
> > !cp /u01/oradata/ora8/rbs02.dbf /var/backup
> > ALTER TABLESPACE RBS END BACKUP;
> >
> > ALTER TABLESPACE TEMP BEGIN BACKUP;
> > !cp /u01/oradata/ora8/temp01.dbf /var/backup
> > ALTER TABLESPACE TEMP END BACKUP;
> >
> > ALTER TABLESPACE TOOLS BEGIN BACKUP;
> > !cp /u01/oradata/ora8/tools01.dbf /var/backup
> > ALTER TABLESPACE TOOLS END BACKUP;
> >
> > ALTER TABLESPACE USERS BEGIN BACKUP;
> > !cp /u01/oradata/ora8/users01.dbf /var/backup
> > ALTER TABLESPACE USERS END BACKUP;
> >
> > and so on BEGIN+cp+END...
> >
> > -----
> >
> > I am very much in favor of the second style, because
> > it minimizes the time that a tablespace is in backup mode.
> >

>

> Hi Jan

>

> Agreed as this means you reduce redo overheads as Oracle takes copies of
> before/after images of each new changed block in it's redo stream to
recover
> from fractured blocks whilst a tablespace is in backup mode (unless you
use
> RMAN).

>

> Look for a post about 12-18 months ago where I explained why this is the
> case.

>
> I would however question taking backups of your temp tablespace, it
suggests
> they're not really temporary tablespaces.

Thanks, I got Your point about this; they are in fact temporary. I just wasn´t sure about
wether I should backup them too or not - now I wont.

greetings,
Jan Received on Wed Feb 25 2004 - 02:19:00 CST