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Message-ID: <59d991c405050908271b55e673@mail.gmail.com>
Date: Mon, 9 May 2005 11:27:54 -0400
From: Christopher Petrilli <petrilli@gmail.com>
Reply-To: Christopher Petrilli <petrilli@gmail.com>
To: Neil Conway <neilc@samurai.com>
Subject: Re: [PERFORM] "Hash index" vs. "b-tree index" (PostgreSQL 8.0)
Cc: Ying Lu <ying_lu@cs.concordia.ca>, pgsql-general@postgresql.org,
	pgsql-performance@postgresql.org
In-Reply-To: <427F757A.8000407@samurai.com>
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References: <427F6853.90308@cs.concordia.ca> <427F757A.8000407@samurai.com>

On 5/9/05, Neil Conway <neilc@samurai.com> wrote:
> I don't think we've found a case in which the hash index code
> outperforms B+-tree indexes, even for "=3D". The hash index code also has
> a number of additional issues: for example, it isn't WAL safe, it has
> relatively poor concurrency, and creating a hash index is significantly
> slower than creating a b+-tree index.

This being the case, is there ever ANY reason for someone to use it?=20
If not, then shouldn't we consider deprecating it and eventually
removing it.  This would reduce complexity, I think.

Chris
--=20
| Christopher Petrilli
| petrilli@gmail.com