Re: Help Me Understand Why I'm Getting a Bad Query Plan - Mailing list pgsql-performance

From Bryan Murphy
Subject Re: Help Me Understand Why I'm Getting a Bad Query Plan
Date
Msg-id 7fd310d10903252100n3ba13c9fuf4818a66cf7afb10@mail.gmail.com
Whole thread Raw
In response to Re: Help Me Understand Why I'm Getting a Bad Query Plan  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-performance
On Wed, Mar 25, 2009 at 10:28 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Bryan Murphy <bmurphy1976@gmail.com> writes:
>> What I did was change seq_page_cost back to 1.0 and then changed
>> random_page_cost to 0.5
>
> [ squint... ]  It makes no physical sense for random_page_cost to be
> less than seq_page_cost.  Please set them the same.
>
>                        regards, tom lane

Done.  Just  saw the tip in the docs as well.  Both are set to 0.5 now
and I'm still getting the good query plan.

Thanks!
Bryan

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