Re: DROP COLUMN uses rollback?

Thanks Jonathan !

I'm trying that now..

sb

"Jonathan Lewis" <jonathan_at_jlcomp.demon.co.uk> wrote in message news:1023400831.7291.0.nnrp-08.9e984b29_at_news.demon.co.uk...
>
> When you go from 'unused' to clearing the columns out, you
> might want to look at:
>
> alter table XXX move nologging;
>
> which will recreate the table with the columns present,
> unavailable, but null - reclaiming most of the space with
> very little undo and redo. And/or
>
> alter table XXX
> drop unused columns
> checkpoint 1000;
>
> which issues an internal commit every 1000 cleaned
> rows, and therefore limits the amount of undo used at
> any instant. (Of course, as a series of small transactions,
> this may cause other long-running processes to hit a
> 1555 error).
>
>
> --
> Jonathan Lewis
> http://www.jlcomp.demon.co.uk
>
> Next Seminars
> UK June / July
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>
> Stephen B wrote in message ...
> >That makes perfect sense...thank you!
> >I'm familiar with the UNUSED option, but I'll need to free up the space
> >eventually...this particular database is in development
> >and will ultimately be deployed accross the country...unfortunately space
> is
> >a consideration in deployment.
> >
> >Thank you especially Howard, for taking the time to clearly delineate why
> >this particular type of DDL requires rollback.
> >
>
>
>
Received on Fri Jun 07 2002 - 09:33:54 CDT