From: tv@fuzzy.cz
To: Joby Joba <jobyjoba59@gmail.com>
Cc: tv@fuzzy.cz
Cc: pgsql-performance@postgresql.org
Subject: Re: Two different execution plans for similar requests
Date: Tue, 1 Mar 2011 10:40:59 +0100
Message-ID: <e54d83f6320c286f51202ad59728e2c9.squirrel@sq.gransy.com> (raw)
In-Reply-To: <AANLkTi=GnN0rytAFvduz3mdpYXh5kBODDQhqk6AAAz8w@mail.gmail.com>
References: <AANLkTinfNhCyMUysjcv2HP6GS6Y_9U9TZgn_QWgXq5Ew@mail.gmail.com>
<bc0d8e3dcc7832b0d29e41de75879087.squirrel@sq.gransy.com>
<AANLkTi=GnN0rytAFvduz3mdpYXh5kBODDQhqk6AAAz8w@mail.gmail.com>
> I've already used an 'EXPLAIN ANALYZE' to post the message. So I don't
> clearly understand what you are expecting for, when you tell me to provide
> 'EXPLAIN ANALYZE' (please excuse me for the misunderstood)
No, you haven't. You've provided 'EXPLAIN' output, but that just prepares
an execution plan and displays it. So it shows just estimates of row
counts etc. and not actual values.
Do the same thing but use 'EXPLAIN ANALYZE' instead of 'EXPLAIN' - it will
run the query and provide more details about it (run time for each node,
actual number of rows etc.).
Anyway the sudden changes of estimated costs are suspicious ...
Tomas
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To: pgsql-performance@postgresql.org
Cc: tv@fuzzy.cz, jobyjoba59@gmail.com
Subject: Re: Two different execution plans for similar requests
In-Reply-To: <e54d83f6320c286f51202ad59728e2c9.squirrel@sq.gransy.com>
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