John, Thanks for the feedback. The code I put up is not part of any real system. I'm just playing off of the existing examples in the docs and trying to get comfortable with SA inheritance.
Randall John M Camara wrote: > > Randall Smith wrote: >> For discussion, consider the Employee, Manager, Engineer example from >> the docs. If I were designing the tables, I would not normally have a >> "type" field. I would use the null status of engineer_info or >> manager_data to determine the employee type. Or if that data was in >> separate tables, I would use the existence of records in those tables. >> And these are simple cases. I can think of some real life cases where >> the values of multiple fields would determine the class. > > IMO you always need to keep your people/place/things data separate from > your roles data. If you put the 2 together you end up developing a > system that is highly inflexible and the code will start to look ugly. > After all a user can wear many hats. He can be an Employee, Manager, > Engineer, etc. He can even be an Employee of 2 different companies, a > manager of multiple groups, etc. > > So I would keep user tables/classes separate from role tables/classes. > For the database design you would have 2 basic choices. > > First option: > > User Table > userID > ... > Role Table > userID > roleType > roleData > ... > > Where roleData would likely contain serialized (pickled) data. > > Second option: > > User Table > id > ... > Role Table > id > userID > roleType > roleDetailsID > ... > Role1Details Table > id > ... > Role2Details Table > id > ... > <other role details tables> > > I would only go with the second option if you actually needed to do ad > hoc queries of the Role#Details tables. Otherwise, the first option is > far quicker to code and provides more flexibility. > > John > > > > > --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "sqlalchemy" group. To post to this group, send email to sqlalchemy@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en -~----------~----~----~----~------~----~------~--~---
