From: Tomas Vondra <tomas.vondra@2ndquadrant.com>
To: pgsql-performance@postgresql.org
Subject: Re: Query > 1000× slowdown after adding datetime comparison
Date: Mon, 31 Aug 2015 18:19:35 +0200
Message-ID: <55E47E97.1090202@2ndquadrant.com> (raw)
In-Reply-To: <1441037351126-5864045.post@n5.nabble.com>
References: <1441037351126-5864045.post@n5.nabble.com>
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On 08/31/2015 06:09 PM, twoflower wrote:
> I have the following three tables:
...
> This is the query plan:
>
> <http://postgresql.nabble.com/file/n5864045/qp1.png;
>
> If I remove the WHERE condition, it returns immediately.
>
> Am I doing something obviously wrong?
Please share explain plans for both the slow and the fast query. That
makes it easier to spot the difference, and possibly identify the cause.
Also, what PostgreSQL version is this, and what are "basic" config
parameters (shared buffers, work mem)?
regards
--
Tomas Vondra http://www.2ndQuadrant.com
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
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To: pgsql-performance@postgresql.org
Cc: tomas.vondra@2ndquadrant.com
Subject: Re: Query > 1000× slowdown after adding datetime comparison
In-Reply-To: <55E47E97.1090202@2ndquadrant.com>
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