Re: incorrect row estimates for primary key join

From: Marcin Mańk <marcin(dot)mank(at)gmail(dot)com>
To: Ben <midfield(at)gmail(dot)com>
Cc: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>, Kevin Grittner <kgrittn(at)ymail(dot)com>, bricklen <bricklen(at)gmail(dot)com>, "pgsql-performance(at)postgresql(dot)org list" <pgsql-performance(at)postgresql(dot)org>
Subject: Re: incorrect row estimates for primary key join
Date: 2013-06-27 00:22:18
Message-ID: CAK61fk5pLO18DwtkCQaMNsrELLWxp=5g6r5RWr09RVG2M34tYA@mail.gmail.com
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On Wed, Jun 26, 2013 at 2:29 AM, Ben <midfield(at)gmail(dot)com> wrote:

> shouldn't an index scan definitely be fastest here? you don't need to touch the whole table or index. maybe there something i have misconfigured here?
>

How about you try increasing work_mem ? I think a hash join may be the
best plan here, and it won't get chosen with low work_mem .

Regards
Marcin Mańk

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