From: Joshua D. Drake <jd@commandprompt.com>
To: Woolcock, Sean <Sean.Woolcock@emc.com>
Cc: salah jubeh <s_jubeh@yahoo.com>
Cc: pgsql-performance@postgresql.org <pgsql-performance@postgresql.org>
Subject: Re: Request for help with slow query
Date: Mon, 29 Oct 2012 12:32:43 -0700
Message-ID: <508ED9DB.2010301@commandprompt.com> (raw)
In-Reply-To: <998490E92A198A48BE60F3A9C44CA3F1010A7DCF3903@MX40A.corp.emc.com>
References: <998490E92A198A48BE60F3A9C44CA3F1010A7DCF3901@MX40A.corp.emc.com>
<1351538299.55595.YahooMailNeo@web122203.mail.ne1.yahoo.com>
<998490E92A198A48BE60F3A9C44CA3F1010A7DCF3903@MX40A.corp.emc.com>
On 10/29/2012 12:25 PM, Woolcock, Sean wrote:
>
> I thought that an index was implicitly created for foreign keys, but I see that that's not true. I've just created one now and re-ran the query but it did not change the query plan or run time.
1. Explain analyze, not explain please
Check to see if estimated rows differs wildly from actual.
2. Seriously... 8.1? That is not supported. Please upgrade to a
supported version of PostgreSQL.
http://www.postgresql.org/support/versioning/
3. Simple things:
A. Have you run analyze on the two tables?
B. What is your default_statistics_target?
Joshua D. Drake
--
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To: pgsql-performance@postgresql.org
Cc: jd@commandprompt.com, Sean.Woolcock@emc.com, s_jubeh@yahoo.com
Subject: Re: Request for help with slow query
In-Reply-To: <508ED9DB.2010301@commandprompt.com>
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