From: "Milen Kulev" <makulev@gmx.net>
To: "'Tom Lane'" <tgl@sss.pgh.pa.us>
Cc: <pgsql-sql@postgresql.org>
Subject: Re: Prepared statements in PGSQL functions 
Date: Wed, 14 Jun 2006 17:16:39 +0200
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-----Original Message-----
From: pgsql-sql-owner@postgresql.org =
[mailto:pgsql-sql-owner@postgresql.org] On Behalf Of Tom Lane
Sent: Wednesday, June 14, 2006 4:35 PM
To: Milen Kulev
Cc: pgsql-sql@postgresql.org
Subject: Re: [SQL] Prepared statements in PGSQL functions=20


"Milen Kulev" <makulev@gmx.net> writes:
>> I want to use prepared statement in a function (your comments below). =
 Wanted
 just to test the difference ...

Why?  You seem not to be aware that plpgsql implicitly prepares =
statements behind the scenes.

&&>> I already have a version with "direct" insert ( just as you say a =
couple of lines below)

> 		prepare  mystmt( int, int, varchar)	as insert into part values =
($1,$2,$3);
> 		execute  mystmt(v_id1, v_id2, v_filler );
> 		deallocate mystmt;

If that worked it would be *exactly* the same as just doing

		insert into part values (v_id1, v_id2, v_filler);

except for being slower due to re-preparing each time through the =
function.  So don't waste your time trying to outsmart
the language.

>> My idea was to prepare the statment once and execute it in a loop  =
many times (within a procedure/function).  Anyway,
obviously there is no performance gain in using prepared statement in =
functions.
Regards. Milen=20

			regards, tom lane

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