Postgres Pro
Downloads
Home   >   mailing lists

Re: incorrect row estimates for primary key join - Mailing list pgsql-performance

From Marcin Mańk
Subject Re: incorrect row estimates for primary key join
Date
Msg-id CAK61fk5pLO18DwtkCQaMNsrELLWxp=5g6r5RWr09RVG2M34tYA@mail.gmail.com
Whole thread Raw
In response to Re: incorrect row estimates for primary key join  (Ben <midfield@gmail.com>)
Responses Re: incorrect row estimates for primary key join  (Ben <midfield@gmail.com>)
List pgsql-performance
Tree view 
On Wed, Jun 26, 2013 at 2:29 AM, Ben <midfield@gmail.com> wrote:

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

pgsql-performance by date:

Previous
From: Josh Berkus
Date:
Subject: Re: Weird, bad 0.5% selectivity estimate for a column equal to itself
Next
From: Ben
Date:
Subject: Re: incorrect row estimates for primary key join