HiThe users list is here http://groups.google.com/group/nhusers
2009/3/2 OmerMor <[email protected]> > > Hello. I have the following object model: > > A top-level abstract class Element with many children and descendants. > A class Event. > Each Element contains a bag of Events. > Each Event has a pointer to the parent Element. > Up till now - pretty standart one-to-many relationship. > > But, I want to use table per concrete class strategy. So, the class > Element is not mapped to the database. I've tried to solve it this > way: each of the concrete descendants of Element defines its own Bag > of Events. The problem with this is that each <bag> element contains a > <key> element. That key points to the Parent property of Event. It > also makes the Parent column in the Events table a foreign key to the > table which contains the Bag! But one column can't be a foreign key to > several tables and I'm getting an exception on insert. > > I've also tried to make the Parent field in the Events table a many-to- > any kind of field. That worked. But when I want to make the relation > bidirectional, meaning, to add the bags to the descendants of Element > I come back to the same problem. Bag => foreign key => exception on > insert. > > I'm sure this case isn't as unique as it seems. Thank you in advance > for your help. > -- Fabio Maulo
