Re: Oddball data distribution giving me planner headaches

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От Jeff Amiel
Тема Re: Oddball data distribution giving me planner headaches
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Msg-id 1322863594.24224.YahooMailClassic@web65509.mail.ac4.yahoo.com
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Ответ на Re: Oddball data distribution giving me planner headaches  ("David Johnston" <polobo@yahoo.com>)
Ответы Re: Oddball data distribution giving me planner headaches
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--- On Fri, 12/2/11, David Johnston <polobo@yahoo.com> wrote:

> From: David Johnston <polobo@yahoo.com>

> ---------------------------------------------------------
> My, possibly naïve, observation:
>
> So aside from the fact the estimates seem to be off the
> planner has still
> chosen the most effective plan?  In that situation no
> matter how accurate
> you get the statistics you will not gain any performance
> because the planner
> will never choose a different plan.
>
Thanks.....
I'm not interested in optimizing this query.....it's fast and efficient.  However, the planner thinks that it is going
toreturn a million rows when it is only going to return one thousand.  When this query is used as an element of a
BIGGERquery, that causes me all sorts of planner issues.... 
That's the problem I am trying to solve...why the planner is 3 orders of magnitude off in row estimation.


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