Benedikt, > > Can somebody tell me how I do :dependent => :destroy without dm-constraints? > > I don't think it will be very easy to do so, although there is some support > for pure-Ruby constraints in dm-constraints. Unfortunately, I do not recall > the details of how it works at the moment. Please have a look at the source > of dm-constraints for more details (it is not terribly large, although it is > a bit convoluted).
The important thing to remember about dm-constraints is that while it does add foreign keys to the tables, they're only used as a "safety net". The real logic happens inside the DM objects, where they will issue destroy commands on each associated object when you use :constraint => :destroy. This is required because :destroy needs to work on a real object in case there are hooks that need to execute after destruction. Really, the only time the foreign keys come into play if something in dm-constraints is broken, otherwise everything happens using the DM objects. This means that dm-constraints works the same way with every DataMapper adapter (aside from the safety net mentioned earlier). -- Dan -- You received this message because you are subscribed to the Google Groups "DataMapper" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/datamapper?hl=en.
