When I was in Greece, I worked in a firm, where every local shop has a local database and the night the shops databases were sending and receiving ASCII files with the transactions between central shop, other shops, and warehouses. The app was in Oracle, PRO*C, and Oracle Forms.
I think now you can have Distributed Database System:
A distributed database is basically a database that is not limited to one system, it is spread over different sites, i.e, on multiple computers or over a network of computers. A distributed database system is located on various sites that don’t share physical components. This may be required when a particular database needs to be accessed by various users globally. It needs to be managed such that for the users it looks like one single database.