Re: benchmarking the query planner

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От Simon Riggs
Тема Re: benchmarking the query planner
Дата
Msg-id 1229101797.8673.56.camel@ebony.2ndQuadrant
обсуждение исходный текст
Ответ на Re: benchmarking the query planner  (Gregory Stark <stark@enterprisedb.com>)
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On Fri, 2008-12-12 at 16:10 +0000, Gregory Stark wrote:
> Uhm, this is a survey of lots of different methods and does lots of
> analysis.
> I don't see any simple conclusions about stability. Perhaps I'm just
> missing
> it in the technical details. Could you point out exactly what part of
> the
> paper you're basing this on and what "stable" means?

I was echoing the comments in the ANALYZE code, which explain that we
use the Duj1 estimator because it is more stable across sample size, as
shown in table 5 on p.21 of the Haas Stokes report.

-- Simon Riggs           www.2ndQuadrant.comPostgreSQL Training, Services and Support



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