On May24, 2012, at 11:39 , Susanne Ebrecht wrote: > There are lots of offices / departments creating maps. Topography maps, > pipeline maps, nature conservancy (e.g. where are the nests from endangered > birds?), mineral resources, wire maps, street maps, bicycle / jogging maps, > tourists maps, tree maps, cadastral land register, and so on. > > All this departments have their own databases for their own maps. > They only map their own stuff. > > Towns / states / regions have a department where all these maps get collected.
The question is, how do they get collected? If they use some home-grown replication, they might just as well collect them into schemas instead of databases. The same is possible with slony, I think. And if they use WAL-based replication, they have no choice but to collect them in different clusters, so cross-database queries within a cluster wouldn't help. I think that you're right that reporting would one of the main use-cases for cross- database queries. But reporting is also, I think, one of the main uses-cases for WAL-based replication. So having cross-database queries with don't allow queries across multiple replicas will leave quite a few people out in the cold. best regards, Florian Pflug -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
