An encapsulation of conflicts that occur during an attempt to save changes in a managed object context.
- iOS 5.0+
- macOS 10.7+
- Mac Catalyst 13.0+Beta
- tvOS 9.0+
- watchOS 2.0+
- Core Data
A conflict can occur in two situations:
Between the managed object context and its in-memory cached state at the persistent store coordinator layer.
Between the cached state at the persistent store coordinator layer and the external store (file, database, and so forth). In this case, the merge conflict has a cached snapshot and a persisted snapshot. The source object is also provided as a convenience, but it is not directly involved in the conflict.
Snapshot dictionaries include values for all attributes and to-one relationships, but not to-many relationships. Relationship values are
NSManaged references. To-many relationships must be pulled from the persistent store as needed.