Re: slow query

From: "Gregory Williamson" <Gregory(dot)Williamson(at)digitalglobe(dot)com>
To: "Scott Marlowe" <scott(dot)marlowe(at)gmail(dot)com>, <pgsql-performance(at)postgresql(dot)org>
Subject: Re: slow query
Date: 2009-01-12 23:38:10
Message-ID: 8B319E5A30FF4A48BE7EEAAF609DB233021F399C@COMAIL01.digitalglobe.com
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Scott Marlowe wrote:

>
> OK, I've got a query that's running slow the first time, then fast.
> But I can't see where the time is really being spend on the first run.
> Query and plan attached to preserve formatting.

Often this is from caching -- the first time the system has to go to disk to get the values; the subsequent times the data (and indexes, presumably) are all in RAM and so much faster.

Is this plausible ?

Greg Williamson
Senior DBA
DigitalGlobe

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  • slow query at 2009-01-12 22:59:24 from Scott Marlowe

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