Re: Sizing Rollbacks segments

In article <918661251.2106.0.nnrp-06.9e984b29_at_news.demon.co.uk>,   "Jonathan Lewis" <jonathan_at_jlcomp.demon.co.uk> wrote:
>
> Mark,
>
> This is the second time you have made this statement
> in the group, and it is simply NOT TRUE. Do you have any
> evidence, or demonstration program that you can quote
> which makes you think that it might be true.
>
> RBS (or undo) consists only of a series of (reverse-)change
> vectors, as far as I know there is NEVER any need for Oracle
> to copy any entire datablock into the RBS.
>
> Jonathan Lewis
> Yet another Oracle-related web site: www.jlcomp.demon.co.uk
>
> mark.powell_at_eds.com wrote in message <79s6mn$j08$1_at_nnrp1.dejanews.com>...
> > The first time you
> delete or change a
> >row in a block the entire block is copied to rbs. The next change in a
> block
> >results in vector information being copied. If the indexes on the table
> are
> >affected by the update/delete then index blocks also are copied to rbs so
> the
> >amount of space required varies from one statement to the next.
> >
>

The information came from Oracle. I will look and see if I can find it. It has been 3 to 4 years since they gave it to me, and my remaining co-worker from then agrees this is what we were told. It may have been verbal from support, who are not always correct, but we were generating huge amounts of rollback and what we were told matched what we saw.

Mark D. Powell -- The only advice that counts is the advice that  you follow so follow your own advice --

-----------== Posted via Deja News, The Discussion Network ==---------- http://www.dejanews.com/ Search, Read, Discuss, or Start Your Own Received on Wed Feb 10 1999 - 15:27:29 CST