Re: [PATCH 10/16] Introduce the concept that wal has a 'origin' node

On Wednesday, June 20, 2012 12:15:03 AM Kevin Grittner wrote:
> Simon Riggs <simon@2ndQuadrant.com> wrote:
> > If we use WAL in this way, multi-master implies that the data will
> > *always* be in a loop. So in any configuration we must be able to
> > tell difference between changes made by one node and another.
> 
> Only if you assume that multi-master means identical databases all
> replicating the same data to all the others.  If I have 72 master
> replicating non-conflicting data to one consolidated database, I
> consider that to be multi-master, too.
> ...
> Of course, none of these databases have the same OID for any given
> object, and there are numerous different schemas among the
> replicating databases, so I need to get to table and column names
> before the data is of any use to me.
Yes, thats definitely a valid use-case. But that doesn't preclude the other - 
also not uncommon - use-case where you want to have different master which all 
contain up2date data.

Andres
-- Andres Freund                       http://www.2ndQuadrant.com/PostgreSQL Development, 24x7 Support, Training &
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