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Re: Standby database and UNRECOVERABLE

From: Chuck <chuckh_at_softhome.net>
Date: Mon, 7 Oct 2002 09:32:32 -0400
Message-ID: <ans2dj$h2bin$1@ID-85580.news.dfncis.de>


Thanks for the reply. The databases in question are 24x7x365 with no quiet time. The indexes in question will be in tablespaces that do not contain any other objects. Since it is a managed standby database all of the archived logs will be copied and applied and I sort of assumed that would be understood since this is a managed standby database. My gut feeling is that it will work. If you think about it, it's not much different than recovering a non-standby database that had a media failure after building an unrecoverable index. You would have taken a backup of the database immediately after the index creation and used that for recovery. In essence it is what I am doing. My standby is the backup of everything but the new index tablespaces. The copy of the index and system tablespaces is the backup of everything else that may have changed.

When I finish I will open it read only and check things out. If I screw up the standby, it is not used for anything other than disaster recovery (which has never been needed in the past) and I can rebuild the whole thing in about 4 hours with little impact on the production database. I realize that what I am doing is not something that would normally be recommended and that is why I post my question here. To get the opinions and suggestions of others (not the attitudes of certain individuals which we could all do without).

I will post the results if anyone cares to see them.

--
Chuck.

"Karsten Farell" <kfarrell_at_medimpact.com> wrote in message
news:acnn9.745$5u3.62169313_at_newssvr13.news.prodigy.com...

> Simply: yes and/or no.
>
> For the 'yes': As you mentioned, copying the data files will require a
> recovery to sync the control files (that step would be the same as if
> you lost the disk on which the index tablespaces were located). That
> means you have to copy more than the data files (ie, some/all of the
> redo or archive log files).
>
> For the 'no': Depending on the current contents of your standby
> database, you could mess things up even more by copying just certain
> pieces of the database. What you're likely to end up with is a database
> that Oracle can't figure out how to properly recover ... the indexes
> will be newer/older than the data they index ... constraints might be
> violated ... and on and on. Oracle recovery (by restoring data files of
> any kind - data/index) is meant to be done against the same database
> they were hot backup'd from.
>
> Conclusion: drop the indexes and recreate them (or rebuild them) ... but
> only if you can find a day or so that you can have the database to
> yourself (it can't be quick to create a 10g+ index).
>
> As for some people who answer a poster's questions with unhelpful
> remarks ... well, I've found you have to have a pretty tough geek-skin
> to dare to post in this newsgroup. There are a lot of helpful people
> here ... I listen to their posts. There are a lot of not-so-helpful
> people here ... I ignore their posts. Works for me. :)
>
> Chuck wrote:
> > One has to wonder whether Sybrand can ever give a straight answer too.
> > Anyone want to try answering the actual question? A simple Yes or No
will
> > do. BTW I figured that performing recovery on the standby was obvious so
I
> > didn't mention it. Perhaps I should have.
> > --
> > Chuck
> >
> > "M Hashim" <m.a.n.hashim_at_sympatico.ca> wrote in message
> > news:A8ln9.16937$Qh1.1765685_at_news20.bellglobal.com...
> >
> >>One wonders whether there is ANY preliminary work done before such a
> >>question is posted. Have to agree with you Sybrand.
> >>
> >>"Sybrand Bakker" <gooiditweg_at_sybrandb.demon.nl> wrote in message
> >>news:3sjrpugg5v43tqi35oet6el8n24bk03vtb_at_4ax.com...
> >>
> >>>On Fri, 4 Oct 2002 11:31:33 -0400, "Chuck" <chuckh_at_softhome.net>
> >>>wrote:
> >>>
> >>>
> >>>>Oracle 8.1.7.
> >>>>
> >>>>I have a primary and a managed standby database. I need to build two
> >>>
> > very
> >
> >>>>large indexes (10g+) on the primary database. If I use the
> >>>
> > unrecoverable
> >
> >>>>option to speed it up, can I copy the datafiles for the tablespaces
> >>>
> > that
> >
> >>>>contain the indexes to the standby database to get the indexes over
> >>>
> > there
> >
> >>or
> >>
> >>>>will I still be missing pieces from the data dictionary? Obviously
this
> >>>>would need to be a hot backup.
> >>>>TIA
> >>>
> >>>
> >>>Try it and report the results.
> >>>or better still: read the manual before screwing up.
> >>>
> >>>
> >>>Regards
> >>>
> >>>
> >>>Sybrand Bakker, Senior Oracle DBA
> >>>
> >>>To reply remove -verwijderdit from my e-mail address
> >>
> >>
> >
> >
>
Received on Mon Oct 07 2002 - 08:32:32 CDT

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