core-dataCreating an Core Data Model


Remarks

Attribute types include: Undefined, Integer 16, Integer 32, Integer 64, Decimal, Double, Float, String, Boolean, Date, Binary, Data, or Transformable

When defining an Entity as abstract you won't be creating any instances of that entity. For example a Person would be abstract and a Employee or Customer would be a concrete subentities.

Transient attributes are properties that you define as part of the model, but which are not saved to the persistent store as part of an entity instance’s data. Core Data does track changes you make to transient properties, so they are recorded for undo operations. You use transient properties for a variety of purposes, including keeping calculated values and derived values.

The Destination field defines what object (or objects) are returned when the relationship is accessed in code.

The Inverse field defines the other half of a relationship. Because each relationship is defined from one direction, this field joins two relationships together to create a fully bidirectional relationship.

Source: Core Data Programming Guide