Message-ID: <44DB6D17.4040902@lsd.di.uminho.pt>
Date: Thu, 10 Aug 2006 18:29:59 +0100
From: alfranio correia junior <alfranio@lsd.di.uminho.pt>
User-Agent: Thunderbird 1.5.0.5 (X11/20060728)
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To: "Jim C. Nasby" <jnasby@pervasive.com>
CC: Markus Schiltknecht <markus@bluegap.ch>,
	Christopher Browne <cbbrowne@acm.org>, pgsql-hackers@postgresql.org
Subject: Re: standard interfaces for replication providers
References: <44D30B31.2070403@lsd.di.uminho.pt>
	<200608041733.24228.jop@lsd.di.uminho.pt>
	<44D70EDA.9060602@bluegap.ch>
	<200608071940.26750.jop@lsd.di.uminho.pt>
	<44D89EA5.5090703@bluegap.ch> <87irl3uqgx.fsf@wolfe.cbbrowne.com>
	<44D8D334.5050808@bluegap.ch> <44D8D9DE.50000@lsd.di.uminho.pt>
	<44D98FCF.90408@bluegap.ch> <20060809185609.GK40481@pervasive.com>
In-Reply-To: <20060809185609.GK40481@pervasive.com>
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>  
> Why reinvent the wheel for everything if there was an interface that
> offered some of the needed functionality? Maybe PostgreSQL-R is simply
> too deep in the database for any of this to be useful, but I'm 99%
> certain that Slony could make use of some of this stuff, such as a hook
> on tuples being written out. Likewise, if there were hooks for WAL
> records and a way to inject WAL info into a backend it probably wouldn't
> be too hard to build WAL-based replication on top of that. Heck, PITR
> could probably be refactored to use such hooks.
>   
Yeah !!!
:-)
The idea is to provide means to inject things at different levels
(statement,
parsed statements, plans, tuples, logs -wal).
So the GAPI provides a generic and standard interface
that enables any application to retrieve information at different
levels and inject information at different levels.

> One of the great things about Oracle is that they expose a hell of a lot
> of the technology they use to build features like replication; ie: take
> a look at DBMS_*.
>   
If I am not wrong such procedures are only for administrative purpose.
For instance,
we cannot insert things in a queue to be replicated.