Date: Sun, 25 May 2008 10:21:33 +0200
From: "Stephen R. van den Berg" <srb@cuci.nl>
To: Decibel! <decibel@decibel.org>
Cc: Richard Huxton <dev@archonet.com>,
	PG Hackers <pgsql-hackers@postgresql.org>,
	Luke Lonergan <LLonergan@greenplum.com>, albert@sedifa.com
Subject: Re: [PERFORM] Posible planner improvement?
Message-ID: <20080525082133.GB27965@cuci.nl>
References: <014F2941B0A1EA47BD61D21526B806E90162C3D2@MI8NYCMAIL08.Mi8.com>
	<48341F1D.3090304@archonet.com>
	<1870DB98-E4E2-4DB5-8620-DB4A8309A73C@decibel.org>
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Decibel! wrote:
>For reference, the original query as posted to -performance:

>select * from t1, t2 where t1.id > 158507 and t1.id = t2.id;

>That took > 84 minutes (the query was a bit longer but this is the  
>part that made the difference) after a little change the query took  
>~1 second:

Just out of curiosity, would predefining the order of join have solved
the issue, as in:

a. select * from t1 join t2 using(id) where t1.id > 158507;
vs.
b. select * from t2 join t1 using(id) where t1.id > 158507;

I'd expect a to be faster than b, is it?
-- 
Sincerely,                                                          srb@cuci.nl
           Stephen R. van den Berg.
"Technology is stuff that doesn't work yet."   --  Bran Ferren
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