I'm thinking advance in time. I'm developing a module, and there are some fields of a custom object whose type isn't really narrowed by the time. I'm using some kind of "loose" type (say, text types) for things that in the future may result to be selections or another type (the use experience will tell what's the best).

How do you manage such changes? How does OpenERP cope with making a change like this? Does any extra step need to be done for updating the database?