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To: Andreas Kretschmer <akretschmer@spamfence.net>
cc: Steve Horn <steve@stevehorn.cc>, pgsql-performance@postgresql.org
Subject: Re: Query slow as Function 
In-reply-to: <20120218160244.GA23315@tux> 
References: 
 <CAFLkBaWRKp7+yVdk3dCecztxEztc+YFS4ks=x3KiSWSfyDZvKw@mail.gmail.com>
	<20120218160244.GA23315@tux>
Comments: In-reply-to Andreas Kretschmer <akretschmer@spamfence.net>
	message dated "Sat, 18 Feb 2012 17:02:44 +0100"
Date: Sat, 18 Feb 2012 11:37:22 -0500
Message-ID: <27854.1329583042@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>
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Andreas Kretschmer <akretschmer@spamfence.net> writes:
> You can check the plan with the auto_explain - Extension, and you can
> force the planner to create a plan based on the actual input-value by
> using dynamic SQL (EXECUTE 'your query string' inside the function)

Steve *is* using EXECUTE, so that doesn't seem to be the answer.  I'm
wondering about datatype mismatches myself --- the function form is
forcing the parameter to be char(9), which is not a constraint imposed
in the written-out query.  There are lots of other possibilities
though.  It would be hard to say much without a self-contained example
to try.

			regards, tom lane