Re: DBMS_REDEF - How online is it, really?
- From: Jinwen Zou <zjworacle@xxxxxxxxx>
- Date: Wed, 12 Feb 2014 10:00:43 +1100
Online redefinition works well. We used it to partition table (around
200-300G, but not TB size) if I remembered correctly.
To speed up the sync temp tab and finish the redef, we force parallel DML
in session level , and cut over in maintenance window for the lock
mentioned.
Regards,
Jinwen Zou
On Wed, Feb 12, 2014 at 3:42 AM, Jonathan Lewis <jonathan@xxxxxxxxxxxxxxxxxx
> wrote:
>
>
> I forgot to mention - there's a short blog that gives you a clue about a
> lock-timing issue that gets addressed in 12c - worth checking to see if
> there's a backport.
>
>
> http://askdba.org/weblog/2013/07/12c-specifying-lock-timeout-for-finish_redef_table/
>
>
>
> Regards
> Jonathan Lewis
> http://jonathanlewis.wordpress.com
> @jloracle
> ------------------------------
> *From:* oracle-l-bounce@xxxxxxxxxxxxx [oracle-l-bounce@xxxxxxxxxxxxx] on
> behalf of Uzzell, Stephan [SUzzell@xxxxxxxxxx]
> *Sent:* 11 February 2014 16:03
> *To:* oracle-l@xxxxxxxxxxxxx
> *Cc:* Uzzell, Stephan
> *Subject:* DBMS_REDEF - How online is it, really?
>
> 11.2.0.3.7 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.
>
>
>
> Thanks!
>
>
>
> *Stephan Uzzell*
>
>
>
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