I don't understand the question. Do you want to share the same DB from two different apps?
I suppose you could copy the models and then set your DB connection strings to point to the same DB. In one app set migrate=False. You might even be able to symbolically link the models from one app to the other. The DAL can work standalone so you could put it in a module, Web2py's site_packages or anywhere in your Python path. If you use it outside it's normal location, include "from gluon.dal import *" at the top of your files and then you should be able to do all the same things (db = DAL(..., db.define_table(...). You mentioned exporting which is quite different. http://web2py.com/book/default/chapter/06?search=Exporting-and-Importing-Data Might need to understand more completely what you are trying to do.
