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Message-ID: <427F9211.2090008@samurai.com>
Date: Tue, 10 May 2005 02:38:41 +1000
From: Neil Conway <neilc@samurai.com>
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To: "Jim C. Nasby" <decibel@decibel.org>
Cc: Christopher Petrilli <petrilli@gmail.com>,
	Ying Lu <ying_lu@cs.concordia.ca>, pgsql-general@postgresql.org,
	pgsql-performance@postgresql.org
Subject: Re: [PERFORM] "Hash index" vs. "b-tree index" (PostgreSQL
References: <427F6853.90308@cs.concordia.ca> <427F757A.8000407@samurai.com>
	<59d991c405050908271b55e673@mail.gmail.com>
	<427F8321.5030702@samurai.com> <20050509163423.GH35026@decibel.org>
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Jim C. Nasby wrote:
> Having indexes that people shouldn't be using does add confusion for
> users, and presents the opportunity for foot-shooting.

Emitting a warning/notice on hash-index creation is something I've 
suggested in the past -- that would be fine with me.

> Even if there is some kind of advantage (would they possibly speed up
> hash joins?)

No, hash joins and hash indexes are unrelated.

-Neil