RE: DBMS_REDEF - How online is it, really?

From: <>
Date: Tue, 11 Feb 2014 11:28:57 -0500
Message-ID: <>

From my experience I remember it worked as advertised.

Only Gotcha was the amount of redo generated and ability to manage that effectively    

[] On Behalf Of Andrew Kerber Sent: Tuesday, February 11, 2014 11:24 AM To: stephan uzzell
Subject: Re: DBMS_REDEF - How online is it, really?  

I have used it with great success. I had a large number of tables we wanted to repartition and wrote a couple of stored procedures to accomplish it. The dbms_Redefinition worked very well.  

On Tue, Feb 11, 2014 at 10:03 AM, Uzzell, Stephan <> wrote: on OEL 6, in case that matters.  

We've been looking into partitioning some large tables (5 trillion rows, 1TB) so that we can better manage them (drop old data, &c.). Right now I'd say dbms_redefinition may be the leading candidate, because Oracle says it is an online operation. I've been burned by Oracle's idea of "online" operations before - alter index rebuild online, if the code is optimized / hinted to use that index, may be online as far as Oracle is concerned, but it sure wasn't for the end users.  

So I'm wondering - has anyone used dbms_redefinition to partition large tables? Is it truly online? Can Oracle keep up with inserts in the meantime?  

We are thinking about using RAT to try to play back a typical workload, but before we open another can of Oracle worms, I figured a question to the list might be a good place to start.  


Stephan Uzzell  

Andrew W. Kerber

'If at first you dont succeed, dont take up skydiving.' 

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Received on Tue Feb 11 2014 - 17:28:57 CET

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