Re: Simple join doesn't use index

From: Merlin Moncure <mmoncure(at)gmail(dot)com>
To: Alex Vinnik <alvinnik(dot)g(at)gmail(dot)com>
Cc: pgsql-performance(at)postgresql(dot)org
Subject: Re: Simple join doesn't use index
Date: 2013-01-29 16:41:47
Message-ID: CAHyXU0xNX7cEnnceshoTi9U1Jpn1zY6T3GuUk6gJMuFJooZmRg@mail.gmail.com
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On Tue, Jan 29, 2013 at 8:41 AM, Alex Vinnik <alvinnik(dot)g(at)gmail(dot)com> wrote:
> Setting work_mem to 64MB triggers in memory sort but look what happens with
> views look up. PG goes through all records there "Seq Scan on views" instead
> of using visitor_id index and I have only subset of real data to play
> around. Can imagine what cost would be running it against bigger dataset.
> Something else is in play here that makes planner to take this route. Any
> ideas how to gain more insight into planner's inner workings?

did you set effective_cache_seize as noted upthread?

merlin

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