Re: Constant WAL replay

Joshua D. Drake wrote:
> Alvaro Herrera wrote:
> > On Sun, Apr 24, 2005 at 08:10:34AM +0200, Hans-J?rgen Sch?nig wrote:
> > 
> > 
> >>The idea: We are looking for a way to implement a synchronous 
> >>single-master / multiple slaves systems.
> >>Meanwhile we are able to serialize / deserialize WAL records and send 
> >>them to a group communication system which transports those records to 
> >>the slave database.
> >>This is not hard to do.
> > 
> > 
> > In fact, I believe Command Prompt's Mammoth Replicator does exactly
> > this.
> 
> Very close. We don't use the WAL (yet, slated for probably 8.1) but we
> do use a transaction log shipping method. So the implementation is 
> almost the same.

Can you run queries on the slave?  If so, how do you handle xid collisions?

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