Re: Rollback segment question

AFAIK ddl statement generates few undo records. No need to worry about rollback segment size for ddl statements.

unrecoverable option (nologging in oracle8) is used to improve the performance for certain dml/ddl statements by reducing the size of redo generated. It does not affect the size of undo.

Thanks
bjin

Sybrand Bakker wrote:

> alter index <index name>
> unrecoverable
> on 7.3 and higher
>
> No need to create that rollback segment...
>
> Hth,
>
> Sybrand Bakker, Oracle DBA
>
> Tapan Trivedi <tapan.trivedi_at_abbnm.com> wrote in message
> news:37A600A4.938647BC_at_abbnm.com...
> > Hey gurus,
> > I have an index which is causing me problems and I have to rebuild. The
> > index is on a very a large table.
> > I am afraid I do not have a big enough Rollback segment to complete the
> > operation. So I will have to create a new Rollback Segment and do a
> > set transaction use rollback segment
> >
> > My problem is how do I estimate how big a rollback segment will the
> > transaction require ? Any ideas , experiences will be appreciated.
> >
> > Tapan H Trivedi
Received on Mon Aug 02 1999 - 22:14:56 CDT