From: Tom Lane <tgl@sss.pgh.pa.us>
To: Віталій Тимчишин <tivv00@gmail.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: correlated exists with join is slow.
Date: Mon, 18 Jun 2012 10:52:35 -0400
Message-ID: <9674.1340031155@sss.pgh.pa.us> (raw)
In-Reply-To: <CABWW-d23upWp8NH=Qr876W5Yd7hqAAabEqXT6tp4TcMfyBK18g@mail.gmail.com>
References: <CABWW-d23upWp8NH=Qr876W5Yd7hqAAabEqXT6tp4TcMfyBK18g@mail.gmail.com>
=?KOI8-U?B?96bUwcymyiD0yc3eydvJzg==?= <tivv00@gmail.com> writes:
> Today I've found a query that I thought will be fast turned out to be slow.
> The problem is correlated exists with join - it does not want to make
> correlated nested loop to make exists check.
9.2 will make this all better. These are exactly the type of case where
you need the "parameterized path" stuff.
regards, tom lane
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To: pgsql-performance@postgresql.org
Cc: tgl@sss.pgh.pa.us, tivv00@gmail.com
Subject: Re: correlated exists with join is slow.
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