Hi,

here is an answer from Bettina Kemme -  author of
Postgres-R - consisent replcation engine based on Postgres 6.4
(URL of paper - http://citeseer.nj.nec.com/330257.html).
While I don't see much activity on replication topic I think it's
worth to discuss with Bettina design issue and co-ordinate
our plans for future release.

	Regards,
		Oleg
_____________________________________________________________
Oleg Bartunov, sci.researcher, hostmaster of AstroNet,
Sternberg Astronomical Institute, Moscow University (Russia)
Internet: oleg@sai.msu.su, http://www.sai.msu.su/~megera/
phone: +007(095)939-16-83, +007(095)939-23-83

---------- Forwarded message ----------
Date: Wed, 02 May 2001 18:26:58 -0400
From: Bettina Kemme <kemme@cs.mcgill.ca>
To: Oleg Bartunov <oleg@sai.msu.su>
Subject: Re: Postgres-R question

Oleg,

we are currently working on producing a Postgres-R
version based on PostgreSQL 6.4 that can be released
for the public. Darren Johnson from sourcesoft institute is
actually working on this version right now.
Since PostgreSQL 7.1 has a quite different concurrency
control system than 6.4, upgrading Postgres-R to 7.1 is a bit more
difficult.
One of my students is going to work on this problem
during the summer (he is going to start next week, but at
the beginning he will have to do some reading to get familiar
with replicated etc).
We would be very happy to cooperate with the PostgreSQL
developers and make the replication part a part of PostgreSQL
(or at least an add-on feature).
The problem is that our approach requires, to a certain degree,
to change the underlying concurrency control method and
the transaction execution control.
That is, different to lazy replication schemes, it will
not be exclusively an add-on feature, but must be integrated into
existing code. Of course,
we are planning to design the system such that the user
(or system administrator) can choose between a replicated
and a non-replicated system. In the non-replicated system,
simply the original PostgreSQL will be executed.

In the next days, I am going to have a closer look at
PostgreSQL 7.1 to figure out  all the details. Again,
we are open for any kind of suggestions, support, cooperation
etc.

	Best
	Bettina

Oleg Bartunov wrote:
>
> Hello,
>
> I found your paper about database replication and your implementation
> based on Postgres. What's the status of your implementation ?
> Is't available for downloading ? I'm postgres developer and interested
> in database replication. Current version of PostgreSQL is 7.1 and
> it has much more feature than that of 6.4.2 but it still lacks replication.
> I think your contribution would be very useful for other users.
>
>         Regards,
>                 Oleg
> _____________________________________________________________
> Oleg Bartunov, sci.researcher, hostmaster of AstroNet,
> Sternberg Astronomical Institute, Moscow University (Russia)
> Internet: oleg@sai.msu.su, http://www.sai.msu.su/~megera/
> phone: +007(095)939-16-83, +007(095)939-23-83

-- 
******************************************
Bettina Kemme
School of Computer Science
McGill University    Phone:  +1 514 398 8930
Montreal, Quebec     Fax:    +1 514 398 3883
Canada               E-mail: kemme@cs.mcgill.ca
http://www.cs.mcgill.ca/~kemme


Thu, 3 May 2001 10:37:09 +0300 (GMT)
Oleg Bartunov <oleg@sai.msu.su>
PostgreSQL replication 