Message-ID: <3E705780.1D3FE1C5@tpf.co.jp>
Date: Thu, 13 Mar 2003 19:03:44 +0900
From: Hiroshi Inoue <Inoue@tpf.co.jp>
MIME-Version: 1.0
To: Dave Page <dpage@vale-housing.co.uk>
Cc: tgl@sss.pgh.pa.us, ZeugswetterA@spardat.at,
	pgman@candle.pha.pa.us, pgsql-hackers@postgresql.org,
	pgsql-interfaces@postgresql.org
Subject: Re: Roadmap for FE/BE protocol redesign
References: <03AF4E498C591348A42FC93DEA9661B8259D8D@mail.vale-housing.co.uk>
	<27130.1047484194@sss.pgh.pa.us> <3E702552.DA8A29A9@tpf.co.jp>
	<50073.80.177.99.193.1047549156.squirrel@ssl.vale-housing.co.uk>
Content-Type: text/plain; charset=iso-2022-jp
Content-Transfer-Encoding: 7bit

Dave Page wrote:
> 
> It's rumoured that Hiroshi Inoue once said:
> > Tom Lane wrote:
> >>
> >> "Dave Page" <dpage@vale-housing.co.uk> writes:
> >> > No, but with them we can avoid cluttering the wire protocol with
> >> > fields for all this, and the JDBC required data. With 2 numeric
> >> > columns (attrelid, attnum), any application/interface can query the
> >> > system catalogs easily for whatever extra info they like.
> >>
> >> This is my feeling also.  We shouldn't try to guess in the protocol
> >> exactly what set of information will be wanted by a frontend; we
> >> should just provide the catalog keys needed to look up whatever is
> >> wanted.
> >
> > Does looking up by the catalog keys take no cost ?
> 
> Obviously there is cost, but doing a lookup only on demand, has got to be
> cheaper in the long run than including the entire column definition in the
> message whether it's wanted or not?

So if there are 100 fields, should we ask the backend 
the column name 100 times ?

regards,
Hiroshi Inoue
	http://www.geocities.jp/inocchichichi/psqlodbc/