I am writing an ORM. I am curious how friend relations are generally modeled. Are they duplicated relations in a link table with each user an owner of his friend relations, or is there an introduction of a mutually owned relation, where the orm looks up relation links where the relation owner's id can be in the child field of the relation link table?
I've never seen an ORM doing your "mutually owned relation" because it would only work for readonly scenarios but ORM is typically for readwrite. i would model them like this