From: Tom Lane <tgl@sss.pgh.pa.us>
To: Kaloyan Iliev Iliev <kaloyan@digsys.bg>
Cc: pgsql-performance@postgresql.org
Subject: Re: Change query join order
Date: Fri, 08 Jan 2010 13:27:03 -0500
Message-ID: <9969.1262975223@sss.pgh.pa.us> (raw)
In-Reply-To: <4B47722A.4010502@digsys.bg>
References: <4B47722A.4010502@digsys.bg>
Kaloyan Iliev Iliev <kaloyan@digsys.bg> writes:
> My question is why the planner didn't do the index scan first on ms_data
> to reduce the rows to ~ 11000 and the use the PK index on
> ms_commands_history.
11000 index probes aren't exactly free. If they take more than about
1msec apiece, the planner picked the right plan.
regards, tom lane
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To: pgsql-performance@postgresql.org
Cc: tgl@sss.pgh.pa.us, kaloyan@digsys.bg
Subject: Re: Change query join order
In-Reply-To: <9969.1262975223@sss.pgh.pa.us>
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