I'm writing an application with PostgreSQL as the database which I would
like to be as modular as possible. It will have various modules, each of
which will have their own database schema. A module with users might
define a user table, but an RPG module would want the user table to have
a column for money. I don't want the users module to know about the RPG
module beforehand, so it can't have the money column. Should the RPG
module subclass the user table and make other modules use its subclass
from now on? Should it just add the column when it's installed? What
have others done?