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Re: pg_hint_plan

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From Robert Klemme <shortcutter@googlemail.com>
Newsgroups comp.databases.postgresql
Subject Re: pg_hint_plan
Date Tue, 17 Feb 2015 08:29:55 +0100
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On 16.02.2015 15:24, Dimitri Fontaine wrote:

> Again, as soon as you use hints, then you need to review every once in a
> while that they are still effective, because they won't be re-evaluated
> against data growth as the usual PostgreSQL statistics system are.

Ideally your database monitoring would catch queries that deteriorate - 
be it because of hints or other reasons.

> Also
> each new version of PostgreSQL will come with a better planner and
> optimiser, so you will need to review all hints and remove the rotted
> ones. Yes, hints rot.

You will want to do testing with any new version of PostgreSQL before it 
goes into production anyway - regardless whether you use hints or not. 
While I agree to the general tendency to rather use automated mechanisms 
of finding a proper plan, this is not a differentiator or a reason 
against hints IMHO.

Kind regards

	robert

-- 
remember.guy do |as, often| as.you_can - without end
http://blog.rubybestpractices.com/

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Thread

pg_hint_plan Mladen Gogala <gogala.mladen@gmail.com> - 2015-02-16 14:07 +0000
  Re: pg_hint_plan Dimitri Fontaine <dimitri@2ndQuadrant.fr> - 2015-02-16 15:24 +0100
    Re: pg_hint_plan Mladen Gogala <gogala.mladen@gmail.com> - 2015-02-16 14:59 +0000
    Re: pg_hint_plan Robert Klemme <shortcutter@googlemail.com> - 2015-02-17 08:29 +0100

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