Re: Bidirectional replication

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> Yeah.  One nasty property that async multi master solutions share is
> that they change the definition of what 'COMMIT' means -- the database
> can't guarantee the transaction is valid because not all the
> supporting facts are necessarily known.  Even after libpq gives you
> the green light that transaction could fail an arbitrary length of
> time later, and you can't rely in the assumption it's valid until
> you've done some synchronizing with the other 'masters'.  Maybe you
> don't need to rely on that assumption so a 'fix it later, or possibly
> never' methodology works well.  Those cases unfortunately fairly rare
> in the real world.

I don't quite follow you here. Are you talking about *synchronous* multi-master?
Async multi-master works just fine, as long as you are not expecting the
servers to give the exact same answer at the exact same time. But certainly
transactions are "valid".

- --
Greg Sabino Mullane greg@turnstep.com
End Point Corporation http://www.endpoint.com/
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