Re: Rollback Segments
Date: Sat, 27 Nov 1993 05:58:46 GMT
Message-ID: <CH4z9y.6nD_at_news.hk.net>
In article <2d0ibu$nai_at_snoopy.sra.com> cohen_at_pni.sra.com (Janine Cohen) writes:
>hello, I am new to using ORACLE V7.0.15 and I have a question about rollback
>segments. I know that each transaction can only write to one rollback
>segment. I have a transaction that delete about 200 megs of information.
>I was wondering if there is any way to get around having a 200 meg rollback
>segment allocated (we don't want to waste so much space if we can help it).
>
>Specifically - is it possible to commit portions of a large delete so that
>that part of the rollback segment info could become inactive and thus reuse
>the existing extents?
>
>I would appreciate any information that you could give me.
>
>Thanks, Jeanine Cohen
> SRA Corporation
> Fairfax, Virginia
>
It is not exactly true that one transaction can only write to one rollback segment. If you perform occasional commits, after each commit the next rollback segment will be assigned in sequence. Once the last rollback segment is reached, it will loop around again. There is a serious flaw in the way rollback segments are designed in Oracle, but that is not the purpose of this reply.
Regards,
S. Tedjarati (stedjara_at_unisys.hk.net)
Unisys Hong Kong and China
Received on Sat Nov 27 1993 - 06:58:46 CET