DataMapper ORM v1.8.2

[eluser]WanWizard[/eluser]
@Maglok,

Datamapper is about relations, it can't produce data in a relation that is not related.

The best option is probably to retrieve all hobbies, and retrieve the person including it's related hobbies. Then iterate over the hobbies, and check if the id exists as a key in persons->hobbies->all. If so, that hobby is related, and if not, well...