Re: database migration

From: Niall Litchfield <niall.litchfield_at_gmail.com>
Date: Tue, 10 Feb 2009 16:49:18 +0000
Message-ID: <7765c8970902100849m173902fcpb9751fc8b4ace2ef_at_mail.gmail.com>



http://www.orafaq.com/wiki/Import_Export_FAQ#Can_one_export_to_multiple_files.3F.2F_Can_one_beat_the_Unix_2_Gig_limit.3F

mknod/mkfifo is your friend here.

On Tue, Feb 10, 2009 at 3:47 PM, Michael Fontana <mfontana_at_enkitec.com>wrote:

> Are you talking about using datapump and pipes?
>
> I am not familiar with using pipes with traditional export/import. If
> it's possible, can you please reference an article or manual that details
> this method?
>
> Thanks!
>
>
>
> -----Original Message-----
> From: Milton, Eric [mailto:Eric.Milton_at_ihs.com]
> Sent: Monday, February 09, 2009 5:47 PM
> To: mfontana_at_enkitec.com; haroon_a_qureshi_at_yahoo.com;
> oracle-l_at_freelists.org
> Subject: RE: database migration
>
> In a situation where I did not want to write scripts I used a pipe to
> export/import with performance that was exceptional. You should be able to
> use many of the standard exp/imp commands. The time on a slow Unix box,
> slow, to move 10,000,000 rows in a 26 column table, was about 15 minutes.
> One very nice feature is the "tiny" amount of disc space you need.
>
> -----Original Message-----
> From: oracle-l-bounce_at_freelists.org [mailto:oracle-l-bounce_at_freelists.org]
> On Behalf Of Michael Fontana
> Sent: Monday, February 09, 2009 1:52 PM
> To: haroon_a_qureshi_at_yahoo.com; oracle-l_at_freelists.org
> Subject: RE: database migration
>
> I would definitely be engaging Oracle support to assist with your
> migration, or at least offer suggestions and best practice methodologies
> since Oracle applications are involved. We found this out when doing an
> Oracle BI and datawarehouse migration!
>
> There are many differences in patch sets and release levels of Oracle
> applications and supporting database between your platforms. You may also
> have to consider what might be running during a phased migration on the
> source that could impact timings (IE - you are migration DB3 while DB1 and
> DB2 are doing heavy batch processing and they slow it down).
>
> I have heard of some people having success with logical sql-apply
> methodologies for migrating databases across platforms, but have no
> experience with it.
>
> Hopefully we have started the ball rolling and you'll get some other
> valuable responses.
>
>
>
>
> -----Original Message-----
> From: Haroon A. Qureshi [mailto:haroon_a_qureshi_at_yahoo.com]
> Sent: Monday, February 09, 2009 2:44 PM
> To: oracle-l_at_freelists.org; Michael Fontana
> Subject: RE: database migration
>
> Thanks Michael. We are running Oracle Applications 11.5.9 and are moving
> to new dell servers with 2 dual core CPUs with 32gb of memory running
> Oracle Enterprise linux 4.7. it is a 10g database (10.2.0.4).
>
> Your initial impression about timing is correct. we are on an aggressive
> schedule and don't have the time to write the scripts and test them out.
> however, if we had a ball park idea of what the savings would be, if any,
> of using rman vs expdp/impdp, we may be able to justify the extra time
> spent on it.
>
> the readonly issue is a big concern, depending on how long it will take to
> export the db or use rman to move it over. we are also planning on moving
> to ASM during the migration.
>
> Thanks in advance for your help.
>
> Haroon
>
> --- On Mon, 2/9/09, Michael Fontana <mfontana_at_enkitec.com> wrote:
>
> > From: Michael Fontana <mfontana_at_enkitec.com>
> > Subject: RE: database migration
> > To: haroon_a_qureshi_at_yahoo.com, oracle-l_at_freelists.org
> > Date: Monday, February 9, 2009, 2:28 PM
> > There are just too many variables to give you a ballpark
> > figure. What is
> > the configuration of your current implementation versus
> > your target
> > hardware? What version(s) of products are you currently
> > running?
> >
> > My initial impression of your statement about not having
> > enough time is
> > that you're going to have to test out your scripts and
> > methodologies
> > regardless of any estimates you might collect from external
> > sources. You
> > simply have to include timing these "rehearsals"
> > you'll be doing to give
> > yourself a fair chance of being able to predict the
> > actuals.
> >
> > Be prepared for some extended downtime - the rman convert
> > methodology
> > requires that the source tablespaces are in READONLY mode
> > during the
> > backup process. If there are any relationships between
> > objects within
> > them, they'll all have to be in that mode for the
> > duration.
> >
> > This is pretty much the case with expdp/impdp as well,
> > although your
> > mileage may vary!
> >
> >
> >
> > -----Original Message-----
> > From: oracle-l-bounce_at_freelists.org
> > [mailto:oracle-l-bounce_at_freelists.org]
> > On Behalf Of Haroon A. Qureshi
> > Sent: Monday, February 09, 2009 2:09 PM
> > To: oracle-l_at_freelists.org
> > Subject: database migration
> >
> > Hello,
> >
> > We are doing a database migration from AIX to Linux. Our
> > database is
> > 600gb. Has anyone used the rman convert database method to
> > migrate the
> > database? Do you have any timings you can share,
> > especially compared to
> > expdp/impdp? Unfortunately, I don't have the luxury of
> > time to try it out
> > myself.
> >
> > Thanks in advance!
> > Haroon
> > --
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> http://www.freelists.org/webpage/oracle-l
>
>
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>
>

-- 
Niall Litchfield
Oracle DBA
http://www.orawin.info

--
http://www.freelists.org/webpage/oracle-l
Received on Tue Feb 10 2009 - 10:49:18 CST

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