> I agree with your disagreement. This design is present in lots of
> non-RDB systems - CVS, IMAP, PDA syncing, etc. It's clearly more
> complicated, but can be made to work, and has been many times. I don't
> see anything about databases in general, or Postgres specifically, that
> indicates it's a bad idea.
>
Depends on what you mean by "work". A database can be made to do lots of
kinds of replication, but there is no perfect solution. The problem
needs to be more clearly defined. In this case, what does the original
poster mean by "synchronize"? It can probably be made to work to his
satisfaction, but not if the synchronization problem is impossible.
If it's simple synchronization, like UNION, you can just use slony-I. If
it's harder, he should examine what each DB has to offer and then
whether that DB actually delivers what it promises, and whether that's
what he actually needs.
Regards,
Jeff Davis