From: Kevin Grittner <Kevin.Grittner@wicourts.gov>
To: tivv00@gmail.com
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: pgsql-performance@postgresql.org
Subject: Re: correlated exists with join is slow.
Date: Mon, 18 Jun 2012 09:58:24 -0500
Message-ID: <4FDEFBC002000025000485EB@gw.wicourts.gov> (raw)
In-Reply-To: <9674.1340031155@sss.pgh.pa.us>
References: <CABWW-d23upWp8NH=Qr876W5Yd7hqAAabEqXT6tp4TcMfyBK18g@mail.gmail.com>
<9674.1340031155@sss.pgh.pa.us>
Tom Lane <tgl@sss.pgh.pa.us> wrote:
> 9.2 will make this all better. These are exactly the type of case
> where you need the "parameterized path" stuff.
Yeah, with HEAD on my workstation all of these queries run in less
than 0.1 ms. On older versions, I'm seeing times like 100 ms to 150
ms for the slow cases. So in this case, parameterized paths allow
an improvement of more than three orders of magnitude. :-)
-Kevin
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To: pgsql-performance@postgresql.org
Cc: Kevin.Grittner@wicourts.gov, tivv00@gmail.com, tgl@sss.pgh.pa.us
Subject: Re: correlated exists with join is slow.
In-Reply-To: <4FDEFBC002000025000485EB@gw.wicourts.gov>
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