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Date: Tue, 24 Apr 2012 10:17:14 +0200
From: Michael Meskes <meskes@postgresql.org>
To: Boszormenyi Zoltan <zb@cybertec.at>
Cc: Noah Misch <noah@leadboat.com>, Michael Meskes <meskes@postgresql.org>,
	Robert Haas <robertmhaas@gmail.com>,
	PG Hackers <pgsql-hackers@postgresql.org>,
	Heikki Linnakangas <heikki.linnakangas@enterprisedb.com>,
	Bruce Momjian <bruce@momjian.us>
Subject: Re: ECPG FETCH readahead
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> OK, I will implement #2. Another question popped up: what to do
> with FETCH ALL? The current readahead window size or temporarily
> bumping it to say some tens of thousands can be used. We may not
> know how much is the "all records". This, although lowers performance,
> saves memory.

I would say doing a large fetch in two or three batches won't cost too mu=
ch in
terms of performance.

> Please, don't apply this patch yet. I discovered a rather big hole
> that can confuse the cursor position tracking if you do this:
> ...
> That will also need a new round of review. Sorry for that.

No problem, better to find it now instead of after release.=20

Anyway, I moved the patch to 2012-next (I hope I did it correctly) so 201=
2-1
can be closed. Let's try to get this patch done in the next commit fest.

Michael
--=20
Michael Meskes
Michael at Fam-Meskes dot De, Michael at Meskes dot (De|Com|Net|Org)
Michael at BorussiaFan dot De, Meskes at (Debian|Postgresql) dot Org
Jabber: michael.meskes at googlemail dot com
VfL Borussia! For=C3=A7a Bar=C3=A7a! Go SF 49ers! Use Debian GNU/Linux, P=
ostgreSQL