Just out of curiousity: Is there a special reason why are you trying to represent a has-a (table A has a relation to table B) relationship with an is-a relationship (class B is a specialization of class A)?
2010/6/17 Paul Harrison <[email protected]>: > > Hi, > > I was wondering if there are any plans for being able to map class > hierarchies - or indeed if anyone has already done such a thing with > Wt::Dbo? > > I can see that it is possible to have a pattern like > > class Base { > int bi; > > template<class Action> > void persist(Action& a) { > dbo::field(a, bi, "bi"); } > > } > class D1 : public Base { > int da; > > template<class Action> > void persist(Action& a) { > base::persist(a); > dbo::field(a, da, "da"); } > > } > class D2 : public Base { > int db; > > template<class Action> > void persist(Action& a) { > base::persist(a); > dbo::field(a, db, "db"); } > > } > > and then > session.mapClass<D1>("D1"); > session.mapClass<D2>("D2"); > > so that there is one (unrelated) table for each subclass (OK if the > base class is abstract). However, it would be nice to be able to map > these classes to 3 related tables where there is a 1-to-1 relation > between the derived class tables and the base class - I don't think > that this is achievable with the current facilities, particularly > without introducing extra members to store the relationships - I think > that it would be desirable if the foreign key relations in the derived > classes were automatically managed. > > Regards, > Paul. > > ------------------------------------------------------------------------------ > ThinkGeek and WIRED's GeekDad team up for the Ultimate > GeekDad Father's Day Giveaway. ONE MASSIVE PRIZE to the > lucky parental unit. See the prize list and enter to win: > http://p.sf.net/sfu/thinkgeek-promo > _______________________________________________ > witty-interest mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/witty-interest > ------------------------------------------------------------------------------ ThinkGeek and WIRED's GeekDad team up for the Ultimate GeekDad Father's Day Giveaway. ONE MASSIVE PRIZE to the lucky parental unit. See the prize list and enter to win: http://p.sf.net/sfu/thinkgeek-promo _______________________________________________ witty-interest mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/witty-interest
