Re: newbie DBA - rollback segments

Mark Perrault wrote:

> I'm new to the oracle dba roll, so please be gentle.
>
> I load several large tables every night. My database is only about
> 20gB and is 24x7. I have 10 rollback segments of 100 mB each. I've
> noticed that the I have a rather high amount of that space getting
> used up (especially after I ran an adhoc UPDATE query on one of those
> large tables). How do I clear the RBS (beyond stopping and restarting
> the instance)? Is there a danger in having 75% or more utilization of
> those RBS's?
>
> Thanks,
> Mark

If it ain't broke don't fix it. From what you've written everything is fine.

You don't clear rollback segments ... you size them large enough to handle the largest transactions (which appears to be the case) and then you leave them alone.

In the future be sure to post hardware, O/S, version and edition. For example if your database is 9.2 you should be using UNDO rather than Rollback.

--
Daniel Morgan
http://www.outreach.washington.edu/extinfo/certprog/oad/oad_crs.asp
damorgan_at_x.washington.edu
(replace 'x' with a 'u' to reply)