Re: 512,600ms query becomes 7500ms... but why? Postgres 8.3 query planner quirk?

From: Kevin Grittner
Subject: Re: 512,600ms query becomes 7500ms... but why? Postgres 8.3 query planner quirk?
Date: ,
Msg-id: 4B753363020000250002F259@gw.wicourts.gov
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In response to: Re: 512,600ms query becomes 7500ms... but why? Postgres 8.3 query planner quirk?  (Karl Denninger)
List: pgsql-performance

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512,600ms query becomes 7500ms... but why? Postgres 8.3 query planner quirk?  (Bryce Nesbitt, )
 Re: 512,600ms query becomes 7500ms... but why? Postgres 8.3 query planner quirk?  (Bryce Nesbitt, )
  Re: Re: 512,600ms query becomes 7500ms... but why? Postgres 8.3 query planner quirk?  (Pavel Stehule, )
  Re: Re: 512,600ms query becomes 7500ms... but why? Postgres 8.3 query planner quirk?  (Robert Haas, )
   Re: Re: 512,600ms query becomes 7500ms... but why? Postgres 8.3 query planner quirk?  ("Jorge Montero", )
   Re: Re: 512,600ms query becomes 7500ms... but why? Postgres 8.3 query planner quirk?  (Bryce Nesbitt, )
    Re: Re: 512,600ms query becomes 7500ms... but why? Postgres 8.3 query planner quirk?  (Tom Lane, )
     Re: Re: 512,600ms query becomes 7500ms... but why? Postgres 8.3 query planner quirk?  (Bryce Nesbitt, )
     Re: Re: 512,600ms query becomes 7500ms... but why? Postgres 8.3 query planner quirk?  (Bryce Nesbitt, )
    Re: Re: 512,600ms query becomes 7500ms... but why? Postgres 8.3 query planner quirk?  (Robert Haas, )
 Re: 512,600ms query becomes 7500ms... but why? Postgres 8.3 query planner quirk?  ("Kevin Grittner", )
  Re: 512,600ms query becomes 7500ms... but why? Postgres 8.3 query planner quirk?  (Karl Denninger, )
   Re: 512,600ms query becomes 7500ms... but why? Postgres 8.3 query planner quirk?  ("Kevin Grittner", )
    Re: 512,600ms query becomes 7500ms... but why? Postgres 8.3 query planner quirk?  (Karl Denninger, )
     Re: 512,600ms query becomes 7500ms... but why? Postgres 8.3 query planner quirk?  ("Kevin Grittner", )
     Re: 512,600ms query becomes 7500ms... but why? Postgres 8.3 query planner quirk?  (Tom Lane, )
      Re: 512,600ms query becomes 7500ms... but why? Postgres 8.3 query planner quirk?  (Bryce Nesbitt, )
       Re: 512,600ms query becomes 7500ms... but why? Postgres 8.3 query planner quirk?  (Pierre Frédéric Caillaud<>, )
       Re: 512,600ms query becomes 7500ms... but why? Postgres 8.3 query planner quirk?  (Robert Haas, )
  Re: 512,600ms query becomes 7500ms... but why? Postgres 8.3 query planner quirk?  (Bryce Nesbitt, )

Karl Denninger <> wrote:
> Kevin Grittner wrote:

>> Have you seen such a difference under 8.4?  Can you provide a
>> self-contained example?

> Yes:
>
> [query and EXPLAIN ANALYZE of fast query]

> The alternative:
>
> [query with no other information]
>
> goes nuts.

Which means what?  Could you post an EXPLAIN ANALYZE, or at least an
EXPLAIN, of the slow version?  Can you post the table structure,
including indexes?

-Kevin


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