Where can I find a good example of a Core Data to-many relationship?

Question

Does anyone have a tutorial or source code that shows a to-many relationship being used, where the user add elements in on the fly? I would just like to have a look because

Answer 1

See Apple's Core Data Programming Guide.

I create objects and add them to relationships using mutableSetValueForKey:

mutableSetValueForKey: returns a mutable proxy object. If you mutate its contents, it will emit the appropriate key-value observing (KVO) change notifications for the relationship.