Re: Suboptimal plan choice problem with 8.3RC2

Guillaume Smet escribió:
> On Jan 22, 2008 8:28 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:

> > I'd expect 8.1 to make about the same estimate given the same stats,
> > so I think it's not looking at the same stats.
>
> Yep, the statistics were the problem, sorry for the noise. The query
> performs in 50ms after an ANALYZE so far better than with 8.1.
>
> The 8.3RC2 box is using the default configuration of autovacuum
> though. Shouldn't it take care of keeping the statistics up to date?
> That's what I thought from what I've read on autovacuum so far (it's
> the first time I use it in "production" though, it was a manual
> process until now) - and that's why I didn't check it. Or should we
> still run the first ANALYZE manually?

No, autovacuum should have taken care of it. I would be interesting in
knowing why it didn't.

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