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From: "EscVector" <Junk@webthere.com>
Newsgroups: comp.databases.oracle.server
Subject: Re: Join selectivity is 0 causing bad cardinality estimates.
Date: 12 Dec 2006 19:59:28 -0800
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So I'm guessing the answer would be, "No, it makes no sense..." :)


Jonathan Lewis wrote:
> <andrew.markiewicz@gmail.com> wrote in message
> news:1165962649.719151.162500@16g2000cwy.googlegroups.com...
> > We also have histograms calculated using a similar method as you have,
> > FOR ALL COLUMNS SIZE AUTO.
> >
>
> That's your main problem.
>
> You don't need histograms on all columns,
> and you don't want to let Oracle work out
> the details.
>
>
> --
> Regards
>
> Jonathan Lewis
> http://jonathanlewis.wordpress.com
>
> Author: Cost Based Oracle: Fundamentals
> http://www.jlcomp.demon.co.uk/cbo_book/ind_book.html
>
> The Co-operative Oracle Users' FAQ
> http://www.jlcomp.demon.co.uk/faq/ind_faq.html