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From: Jim C. Nasby <jim@nasby.net>
To: Merlin Moncure <mmoncure@gmail.com>
Cc: Carlo Stonebanks <stonec.register@sympatico.ca>
Cc: pgsql-performance@postgresql.org
Subject: Re: Performance Optimization for Dummies 2 - the SQL
Date: Sun, 8 Oct 2006 15:34:50 -0500
Message-ID: <20061008203450.GK72517@nasby.net> (raw)
In-Reply-To: <b42b73150610050630t76e9eedeh45a382729d35f2f6@mail.gmail.com>
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On Thu, Oct 05, 2006 at 09:30:45AM -0400, Merlin Moncure wrote:
> I personally only use explicit joins when doing outer joins and even
> them push them out as far as possible.

I used to be like that too, until I actually started using join syntax.
I now find it's *way* easier to identify what the join conditions are,
and to seperate them from the rest of the where clause. It also makes it
pretty much impossible to mess up a join clause and get a cartesian
product.

If you are going to put the join clauses in the WHERE clause, at least
put a space between the join stuff and the rest of the WHERE clause.

In any case, this is nothing but a matter of taste in this case, unless
you set join_collapse_limit to less than 3 (or maybe 4).
-- 
Jim Nasby                                            jim@nasby.net
EnterpriseDB      http://enterprisedb.com      512.569.9461 (cell)



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