Re: not in(subselect) in 8.4

From: Grzegorz Jaśkiewicz <gryzman(at)gmail(dot)com>
To: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Cc: "pgsql-performance(at)postgresql(dot)org" <pgsql-performance(at)postgresql(dot)org>
Subject: Re: not in(subselect) in 8.4
Date: 2009-02-21 17:10:16
Message-ID: 2f4958ff0902210910h3c87f0deo5b9d70fac138b1ae@mail.gmail.com
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the foo bar example above, with notion that all columns are NOT NULL
behaves much different now. I noticed, that some of the 'anti join'
stuff has changed in cvs recently, but I don't know if that's to
blame.
Basically, what I can see, is that the subselect case is no longer of
lower cost, to the left join - but is quite substantially more
expensive.

Just an observation, I don't intend to use subselects anyhow, because
these are very much slower on 8.3, which we use in production here.

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