Obviously I didn't mean everyone. Sorry for that. The I'm trying to
make is that evryone I talk to including Oracle and my own DBA's,
friends etc say there is an overhead with local indexes and that's it.
It seems I have to go to great lengths to convince poeple otherwise. I
have now added some example PL/SQL to verify the point and this also
concludes it is nothing to do with striping or parallelism.
"Jonathan Lewis" <jonathan_at_jlcomp.demon.co.uk> wrote in message news:<1028921852.29308.0.nnrp-01.9e984b29_at_news.demon.co.uk>...
> Comments inline.
>
> --
> Regards
>
> Jonathan Lewis
> http://www.jlcomp.demon.co.uk
>
> Next Seminars
> UK Sept, Nov
> USA x 2 November
>
> http://www.jlcomp.demon.co.uk/seminar.html
>
> Michael Burden wrote in message
> <3bbc0756.0208080127.61a916cb_at_posting.google.com>...
> >
> >Everyone seems against local indexes but why.
> >
>
> This seems to be a rather extreme comment, given
> that only two other people have participated in this
> thread so far.
>
> Just for the record - local indexes are a 'good thing'
> and can be used very effectively. The arithmetic in
> the example you give is, however, well-known as
> defining a potential overhead.
>
> >
> >Now as the data is striped (or perhaps even better each partition is
> >on a different disk) each of the 10 partitions can be run in parallel
> >and so the actual response time could be quicker.
> >
>
>
> Your arithmetic is perfectly sound, but the response
> time you are seeing is not as expected. Perhaps the
> paragraph above is a hint at the real problem - are
> you making this query run in parallel - if so, how many
> ways, and is it possible that most of the excess 3-4
> seconds is in the PX setup ?
Received on Mon Aug 12 2002 - 16:44:02 CDT
