On Tue, Oct 16, 2007 at 08:58:07AM +0100, Peter Geoghegan wrote:
>  
> The question is, can I use slony-I in this way to retrieve this
> information from the slaves, or will I need to devise another
> mechanism, such as accrueing sales as XML or something, and sending
> them via some generic messaging protocol (the system is implemented
> in C++) ?,

You can do it with Slony, but you'll need to jump through some hoops
to manage it, I suspect.

The key is to see that Slony doesn't replicate a _database_, but a
set of tables.  So there's a set that contains the data that every
node needs, and that is replicated to all the "remote" nodes.  Then,
each "remote" node has a set of local tables which are replicated to
the "central" node.  You'll probably want a view on the "central"
system that allows it to view the aggregated data from all the
"remote" nodes.  You'll also need to do some scripting, I think, to
make this system even somewhat sane to manage.

A

-- 
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When my information changes, I alter my conclusions.  What do you do sir?
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