I have a system which is in the middle of an upgrade, and during the
upgrade some people will be working (using) the new system and others
on the old one (systems have different DB but on the same cluster).

The problem I have is that certain information has to be updated on
both DBs, specifically, data loaded on the old DB should be passed to
the new DB.

I thought about slony right away, but wanted to know how feasible it
may be (no need for synchronous updates). Structure of the relations
involved in the synchronization are the same.

Is it a good solution?

-- 
Martín Marqués
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DBA, Programador, Administrador