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"Rob Fegan" <l120bj_at_aol.com> wrote in message
news:20010217051545.28493.00001332_at_ng-cn1.aol.com...
> >Subject: Problem
> >From: francis_at_mail.com (FL)
> >Date: 2/17/01 7:31 AM GMT Standard Time
> >Message-id: <3a8e28bb.4294605_at_news.i-cable.com>
> >
> >What is the difference of noarchivelog mode or archivelog mode?
> >
>
> Hi Francis,
> Archivelog mode means that the Oracle online redo logs are archived to
> separate files before the are re-used by the database.
Sorry to be picky Rob, but archivelog mode doesn't mean that at all. Archivelog simply means that online redo logs are not over-written *unless* they've been archived. Setting archivelog mode says absolutely nothing about how, when or where the actual archiving should take place... for that, you have to set the init.ora parameters.
I wouldn't normally worry about the distinction, except that I can't tell you how many times I see people doing an 'alter database archivelog', and then wondering why their database hangs, ten minutes and a few transactions later.
Yet issuing that command undoubtedly puts your database into archivelog mode as a quick glance at v$database will tell you.
I know what you meant, however, and everything you write below is spot on.
Regards
HJR
>This means that if you
> have a backup of the database and all archived logs generated since the
backup
> then you should be able to restore your database to the point of failure.
> If you are running noarchivelog mode and any of your online redo logs
have
> been overwritten by the database - commonly called 'wrapped' - since the
last
> backup then you will only be able to recover to the time of the last
backup.
> Regards,
> Rob
Received on Sat Feb 17 2001 - 15:25:35 CST