Re: Question about undo

From: Palooka <>
Date: Tue, 29 Jul 2008 20:33:51 +0100
Message-ID: <IgKjk.92805$Gb2.78403@newsfe29.ams2> wrote:
> Hi,
> We just migrated to Oracle 10g, from 8i. We had one question about
> UNDO. The documentation states that the UNDO table space keeps the
> 'undo' information for whatever time you specify and then writes it to
> disk.
> Does this mean that the rollback segments are no longer used and can
> be removed/deleted from the system/init.ora?

Basically, yes. As I understand it, one merely specifies an undo tablespace of sufficient size and lets oracle get on with it. Parameters are UNDO_MANAGEMENT=AUTO and UNDO_TABLESPACE. Forget rollback segments.

It's useful to look up UNDO_RETENTION too.

And btw, these days it's probably a good idea to use an spfile rather than an init.ora.

Palooka Received on Tue Jul 29 2008 - 14:33:51 CDT

Original text of this message