From: Bruce Momjian <pgman@candle.pha.pa.us>
Message-Id: <200204160357.g3G3vKi06010@candle.pha.pa.us>
Subject: Re: [SQL] 16 parameter limit
In-Reply-To: <20020415235216.5bdf393a.nconway@klamath.dyndns.org>
To: Neil Conway <nconway@klamath.dyndns.org>
Date: Mon, 15 Apr 2002 23:57:20 -0400 (EDT)
Cc: Christopher Kings-Lynne <chriskl@familyhealth.com.au>,
	peter_e@gmx.net, tgl@sss.pgh.pa.us, josh@agliodbs.com,
	jproctor@prium.net, pgsql-patches@postgresql.org
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Neil Conway wrote:
> On Tue, 16 Apr 2002 11:35:57 +0800
> "Christopher Kings-Lynne" <chriskl@familyhealth.com.au> wrote:
> > > > Are we staying at 16 as the default?   I personally think we can
> > > > increase it to 32 with little penalty,
> > >
> > > If you want to increase it, let's just increase it and not add any more
> > > configure options.  If someone wants more than 32 then we really need to
> > > start talking about design issues.
> > 
> > Why not give them the configure option?  It's not good HCI to impose
> > arbitrary limits on people...?
> 
> It's not an arbitrary limit -- users can easily change pg_config.h.

Let me just point out that you have to change pg_config.h.in and run
configure _or_ change pg_config.h and _never_ run configure again.  It
is this complexity that makes a configure option look acceptable.

Maybe we should pull some of the hard-coded, non-configure stuff from
pg_config.h into a separate file and just include it from pg_config.h.

> > We can default it to 32, since there's demand for it.  If a particular user
> > decided to configure it higher, then they do that knowing that it may cause
> > performance degradation.  It's good to give them that choice though.
> 
> What if someone actually uses functions with more than 32
> arguments? Their code will not longer be portable among
> PostgreSQL installations, and they'll need to get the local
> admin to recompile.


It is usually C++ overloading functions that use lots of args, or
functions that pass every table column into the function.  In those
cases, I can easily see 32 params.

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