Message-ID: <4C23596C.4080904@cybertec.at>
Date: Thu, 24 Jun 2010 15:11:08 +0200
From: =?UTF-8?B?QsO2c3rDtnJtw6lueWkgWm9sdMOhbg==?= <zb@cybertec.at>
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To: Michael Meskes <meskes@postgresql.org>
CC: Bruce Momjian <bruce@momjian.us>,
	PG Hackers <pgsql-hackers@postgresql.org>,
	Hans-Juergen Schoenig <hs@cybertec.at>
Subject: Re: ECPG FETCH readahead
References: <201006232042.o5NKgb503695@momjian.us>
	<4C2308FD.1090300@cybertec.at>
	<20100624121335.GC24137@feivel.credativ.lan>
In-Reply-To: <20100624121335.GC24137@feivel.credativ.lan>
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2010-06-24 14:13 keltezéssel, Michael Meskes írta:
>> I think, yes, it does make sense. Because we are talking
>> about porting a whole lot of COBOL applications.
>>      
> COBOL???
>    

Yes, OpenCOBOL...

>> The ESQL/C or ECPG connector was already written
>> the Informix quirks in mind, so it fetches only one record
>> at a time passing it to the application. And similar performance
>> is expected from ECPG - which excpectation is not fulfilled
>> currently because libecpg doesn't do the same caching as
>> ESQL/C does.
>>      
> Eh, you are talking about a program you wrote for your customer or they wrote
> themselves, right? I simply refuse to add this stuff only to fix this situation
> for that one customer of yours if it only hits them. Now the thing to discuss
> is how common is this situation.
>    

The OpenCOBOL database connector was written by them
but the problem is more generic. There are many "naive"
applications (elsewhere, too) using cursors but fetching
one record at a time perhaps for portability reasons.
This patch provides a big performance boost for those.

Best regards,
Zoltán Böszörményi