Date: Wed, 1 Mar 2006 13:28:03 -0500
From: Andrew Sullivan <ajs@crankycanuck.ca>
To: pgsql-sql@postgresql.org
Subject: Re: Replication - state of the art?
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On Wed, Mar 01, 2006 at 09:51:46AM -0800, Bryce Nesbitt wrote:
> switch over and rebuild the DB.  "No-lost transaction" is far more
> important than switch time.

You can't guarantee that without two phase commit, no matter what you
do.  Log shipping doesn't require you to have an active database
running on the origin (slony-1 does, which is one of its potential
drawbacks).  But that won't help you if a transaction committed at
the instant an earthquake hit your datacentre, wiping it out.  You
can't get the data off the failed origin no matter what. 

> Anyone here using replication or transaction journaling?  Has it proved
> reliable, easy to maintain?

Define "easy".  Every possible replication system is going to have
slightly grotty corners into which you find yourself wandering.  The
question is merely whether the room is octagonal or merely
rectangular.

A

-- 
Andrew Sullivan  | ajs@crankycanuck.ca
I remember when computers were frustrating because they *did* exactly what 
you told them to.  That actually seems sort of quaint now.
		--J.D. Baldwin