Re: binary patch problems

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: pgsql-jdbc(at)postgresql(dot)org
Subject: Re: binary patch problems
Date: 2011-09-19 14:47:12
Message-ID: 16752.1316443632@sss.pgh.pa.us
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Mikko Tiihonen <mikko(dot)tiihonen(at)nitorcreations(dot)com> writes:
> On 09/19/2011 01:11 PM, Bodor Andras wrote:
>> Why don't you set prepareThreshold to 0 for your test cases?
>> In this case parameter passing starts immediately for the
>> prepared statement, and ForceBinaryTransfers can be dropped.

> AbstractJdbc2Statement:
> public boolean isUseServerPrepare() {
> return (preparedQuery != null && m_prepareThreshold != 0 && m_useCount + 1 >= m_prepareThreshold);
> }

> If I read the above correctly then prepareThreshold of 0 disables prepared statements.

But "1" would do what you want, no?

FWIW, I'm hoping that this entire business of delaying the server-side
prepare will be obsolete as of 9.2. There is already code committed in
HEAD that allows "prepared" statements to be re-planned for each new set
of parameter values, with a somewhat-informed choice of whether and when
to switch over to the traditional generic-plan approach. It needs
tweaking for performance still, no doubt, but there is not going to be a
reason for the driver to do this anymore.

Obviously that's not much use for solving your immediate problem, but it
might lead you to conclude that putting a large amount of effort into
improving this mechanism would be a dead end.

regards, tom lane

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