Received: from localhost (unknown [200.46.208.211])
	by mail.postgresql.org (Postfix) with ESMTP id 71C0B634E63
	for <pgsql-jdbc-postgresql.org@mail.postgresql.org>;
	Tue, 10 Mar 2009 05:06:02 -0300 (ADT)
Received: from mail.postgresql.org ([200.46.204.86])
	by localhost (mx1.hub.org [200.46.208.211]) (amavisd-maia, port 10024)
	with ESMTP id 59026-09 for
	<pgsql-jdbc-postgresql.org@mail.postgresql.org>;
	Tue, 10 Mar 2009 05:05:53 -0300 (ADT)
X-Greylist: from auto-whitelisted by SQLgrey-1.7.6
Received: from mail.mnc.ch (62-2-77-205.static.cablecom.ch [62.2.77.205])
	by mail.postgresql.org (Postfix) with ESMTP id BA509634C78
	for <pgsql-jdbc@postgresql.org>; Tue, 10 Mar 2009 05:05:56 -0300 (ADT)
Received: from localhost (mail2.mnc.ch [127.0.0.1])
	by mail.mnc.ch (Postfix) with ESMTP id 53B2C23079;
	Tue, 10 Mar 2009 08:05:51 +0000 (GMT)
X-Virus-Scanned: amavisd-new at mnc.ch
Received: from mail.mnc.ch ([127.0.0.1])
	by localhost (mail2.mnc.ch [127.0.0.1]) (amavisd-new, port 10025)
	with ESMTP id xMHXpxFuODNA; Tue, 10 Mar 2009 08:05:51 +0000 (GMT)
Received: from meuh.localdomain (62-2-77-204.static.cablecom.ch [62.2.77.204])
	by mail.mnc.ch (Postfix) with ESMTP id 003DA23020;
	Tue, 10 Mar 2009 08:05:50 +0000 (GMT)
Received: by meuh.localdomain (Postfix, from userid 1000)
	id 1ABDFDF23A; Tue, 10 Mar 2009 09:05:52 +0100 (CET)
To: Oliver Jowett <oliver@opencloud.com>
Cc: pgsql-jdbc@postgresql.org
Subject: Re: [PERFORM] Query much slower when run from postgres 	function
References: <49B51B60.6030600@megafon.hr> <27649.1236616294@sss.pgh.pa.us>
	<87fxhmmygj.fsf@meuh.mnc.lan>
	<1d4e0c10903091004m758d7ea2s91e33631be81215a@mail.gmail.com>
	<5165.1236618994@sss.pgh.pa.us>
	<491f66a50903091256n7fe4a3f6i93267d0d53b983cb@mail.gmail.com>
	<49B58ABE.7070105@opencloud.com>
From: Guillaume Cottenceau <gc@mnc.ch>
X-Hashcash: 
 1:20:090310:oliver@opencloud.com::ZkggUnb5tUxYGHyu:000000000000000000000000000000000000000009Ptr
X-Hashcash: 
 1:20:090310:pgsql-jdbc@postgresql.org::6sfTxrGZ3NI5dbrB:0000000000000000000000000000000000000/ZC
Date: Tue, 10 Mar 2009 09:05:52 +0100
In-Reply-To: <49B58ABE.7070105@opencloud.com> (Oliver Jowett's message of
	"Tue\, 10 Mar 2009 10\:31\:42 +1300")
Message-ID: <87bps9ls4f.fsf@meuh.mnc.lan>
User-Agent: Gnus/5.11 (Gnus v5.11) Emacs/22.3 (gnu/linux)
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
X-Virus-Scanned: Maia Mailguard 1.0.1
X-Spam-Status: No, hits=0 tagged_above=0 required=5 tests=none
X-Spam-Level: 
X-Archive-Number: 200903/49
X-Sequence-Number: 19379

Oliver Jowett <oliver 'at' opencloud.com> writes:

> The idea behind the threshold is that if a PreparedStatement object is
> reused, that's a fairly good indication that the application wants to
> run the same query many times with different parameters (since it's
> going to the trouble of preserving the statement object for reuse). But

Or it may just need the safeness of driver/database parameter
"interpolation", to get a "free" efficient safeguard against SQL
injection. As for myself, I have found no other way to obtain
driver/database parameter interpolation. So sometimes I use
prepared statements even for running a query only once. I am
unsure it is a widely used pattern, but SQL injection being quite
important to fight against, I think I may not be the only one.

-- 
Guillaume Cottenceau