From: Jonah H. Harris <jonah.harris@gmail.com>
To: Josh Trutwin <josh@trutwins.homeip.net>
Cc: pgsql-performance@postgresql.org
Subject: Re: PostgreSQL vs MySQL, and FreeBSD
Date: Fri, 16 Nov 2007 15:53:51 -0500
Message-ID: <36e682920711161253l4376c96ap95fb494c7e24874f@mail.gmail.com> (raw)
In-Reply-To: <20071116143650.03e994ad@prokofiev.trutwins.homeip.net>
References: <47344D43.5090506@geri.cc.fer.hr>
<47347F9F.1070309@laliluna.de>
<1195206185.29253.56.camel@neuromancer.home.net>
<01c601c82869$3ffb2580$8e00a8c0@tridecap.com>
<36e682920711160806k359a8825ia0d962d7ac6f6d7b@mail.gmail.com>
<20071116143650.03e994ad@prokofiev.trutwins.homeip.net>
On Nov 16, 2007 3:36 PM, Josh Trutwin <josh@trutwins.homeip.net> wrote:
> > Agreed. IMHO, there's nothing wrong with nested-loop join as long
> > as it's being used properly.
>
> Can you explain further please? (I'm not disagreeing with you, just
> want to know when nested loops are not used properly - does the
> planner make mistakes that you have to watch out for?)
As long as statistics are updated properly, it's generally not an
issue. You just don't want the system using a nested-loop join
incorrectly (like when table sizes are equal, the outer table is
larger than the inner table, or the inner table itself is overly
large).
--
Jonah H. Harris, Sr. Software Architect | phone: 732.331.1324
EnterpriseDB Corporation | fax: 732.331.1301
499 Thornall Street, 2nd Floor | jonah.harris@enterprisedb.com
Edison, NJ 08837 | http://www.enterprisedb.com/
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To: pgsql-performance@postgresql.org
Cc: jonah.harris@gmail.com, josh@trutwins.homeip.net
Subject: Re: PostgreSQL vs MySQL, and FreeBSD
In-Reply-To: <36e682920711161253l4376c96ap95fb494c7e24874f@mail.gmail.com>
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