From: Michael A Nachbaur <mike@nachbaur.com>
To: Cliff Wells <LogiplexSoftware@earthlink.net>,
	pgsql-sql@postgresql.org
Subject: Re: Home-brewed table syncronization
Date: Wed, 9 Jul 2003 14:50:32 -0700
User-Agent: KMail/1.5
References: <200307091414.19959.mike@nachbaur.com>
	<1057786137.15508.29.camel@software1.logiplex.internal>
In-Reply-To: <1057786137.15508.29.camel@software1.logiplex.internal>
MIME-Version: 1.0
Content-Type: text/plain;
  charset="iso-8859-1"
Content-Transfer-Encoding: 7bit
Content-Disposition: inline
Message-Id: <200307091450.32440.mike@nachbaur.com>

On Wednesday 09 July 2003 02:28 pm, Cliff Wells wrote:
> On Wed, 2003-07-09 at 14:14, Michael A Nachbaur wrote:
> > So, I'm looking at syncronizing 4 tables from one master database to
> > several child databases. I'm thinking of doing the following with
> > DBD::Multiplex:
> >
> > DELETE FROM TableA;
> > INSERT INTO TableA (..) VALUES (...);
> > ....
> >
> > on all the child databases, but I'm not sure what kind of impact this
> > would have on my servers.  My impression is that this would hammer the
> > indexes, and might blow any memory optimization out the window.  Only a
> > few records in my dataset will change from time-to-time, but just the
> > process of determining what is different may take more effort than simply
> > rebuilding.
>
> Keep a timestamp associated with each record.  Only update the records
> with timestamps later than your last sync.

I'm dealing with an existing database structure that, though I can change it, 
has a lot of impact on the rest of my infrastructure.  If I can find a way of 
doing this without resorting to timestamps, I'd much rather do it that way.

-- 
/* Michael A. Nachbaur <mike@nachbaur.com>
 * http://nachbaur.com/pgpkey.asc
 */

"Rome wasn't burned in a day. "