Re: Importance of archivelog : searching for good document

From: Seth Miller <sethmiller.sm_at_gmail.com>
Date: Tue, 10 Mar 2015 17:26:34 -0500
Message-ID: <CAEueRAU4e7py4D91B-i=yB7EZb5BBRma43vcqZgODAQejv=CeQ_at_mail.gmail.com>



So much passion in these responses which is a good thing when it comes to recovery.

The decision of archivelog versus noarchivelog comes down to RPO, feature need and tolerance for downtime which means the right answer depends completely on the needs of the user.

If my RPO is 24 hours, I have no need for mining logs, flashback database doesn't matter and I can take an outage every night for a consistent backup, and I don't have the space for archive logs -- should I run in archivelog mode anyway because "it's always better"?

Here's another example:

My RPO is five minutes. My database is small and multi-mastered. The change rate in my database is incredibly high and I've determined that trying to support the archive logs generated is much more expensive than adding enough databases to my replication cluster to support taking one of them down every five minutes to do a backup.

If you are looking for arguments for or against archivelog mode, I would suggest that there is a need to check your premises since one is not inherently better than the other.

Seth Miller

On Tue, Mar 10, 2015 at 4:59 PM, Andrew Kerber <andrew.kerber_at_gmail.com> wrote:

> I have run into two cases where archive logging was not needed. Of course
> neither was Oracle needed, but they used it anyway. Both were classic
> examples of when your only tool is a hammer every problem looks like a
> nail. My initial recommendation in both cases was to rewrite in a
> scripting language or a 3GL.
>
> Sent from my iPad
>
> > On Mar 10, 2015, at 3:43 PM, MacGregor, Ian A. <ian_at_slac.stanford.edu>
> wrote:
> >
> > Who is arguing against archive logging and to what benefit. I would not
> want to be responsible for any type of backup/recovery in this situation.
> I’d insist on archive logging or insure whomever does not want archive
> logging implemented totally responsible for the backups.
> >
> > Ian MacGregor
> > SLAC National Accelerator Center
> >> On Mar 10, 2015, at 10:39 AM, kyle Hailey <kylelf_at_gmail.com> wrote:
> >>
> >>
> >>
> >> Does any one know of a good document or blog that argues strongly for
> archive log?
> >>
> >> Most of the stuff I see says you can use archive log if you want but
> you don't have to and if you don't it just means you have to take cold
> backups and can't do point in time recovery
> >>
> >> The way I look at it is point in time recovery is crucial because you
> will corrupt your database at some point without archive log it's just
> matter of time, a ticking time bomb.
> >>
> >>
> >>
> >> - Kyle
> >
> > †Ûiÿü0ÁúÞzX¬¶Ê+ƒü n– {ú+iÉ^
> --
> http://www.freelists.org/webpage/oracle-l
>
>
>

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Received on Tue Mar 10 2015 - 23:26:34 CET

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