From: Florian Weimer <fweimer@bfk.de>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: pgsql-performance@postgresql.org
Subject: Re: Odd estimation issue with user-defined type
Date: Fri, 03 Sep 2010 15:28:19 +0000
Message-ID: <824oe6lucs.fsf@mid.bfk.de> (raw)
In-Reply-To: <23120.1283526855@sss.pgh.pa.us>
References: <82zkvyncaw.fsf@mid.bfk.de>
<23120.1283526855@sss.pgh.pa.us>
* Tom Lane:
>> Any idea what could cause this? Do I need to provide some estimator
>> function somewhere?
>
> If you haven't, then how would you expect the planner to know that?
Perhaps it's psychic, or there is some trick I don't know about? 8-)
> Less flippantly, you really need to tell us exactly what planner support
> you did provide, before you can expect any intelligent comment. Has the
> type got a default btree opclass?
Yes, I think so (because of CREATE OPERATOR CLASS ... USING btree).
> What selectivity estimators did you attach to the comparison
> operators?
Ah, I see, I probably need to provide a RESTRICT clause in the
operator definition. That should do the trick, and should be fairly
easy to implement in this case.
Sorry, I just missed this piece of information in the documentation, I
should have read it more carefully.
--
Florian Weimer <fweimer@bfk.de>
BFK edv-consulting GmbH http://www.bfk.de/
Kriegsstraße 100 tel: +49-721-96201-1
D-76133 Karlsruhe fax: +49-721-96201-99
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To: pgsql-performance@postgresql.org
Cc: fweimer@bfk.de, tgl@sss.pgh.pa.us
Subject: Re: Odd estimation issue with user-defined type
In-Reply-To: <824oe6lucs.fsf@mid.bfk.de>
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