Relationships
One of the benefits of using Core Data is that entities can be related to one another in a way that allows you to describe complex models. Relationships between entities are represented by references between objects. There are two kinds of relationships: to-one and to-many.
When an entity has a to-one relationship, each instance of that entity has a reference to a single instance of another entity.
When an entity has a to-many relationship, each instance of that entity has a reference to a Set. This set contains the instances of the entity that it has a relationship with. To see this in action, you are going to add a new entity to the model file.
Open the Photorama application. In Photorama.xcdatamodeld, add an ...
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