An encapsulation of conflicts that occur during an attempt to save a managed object.
- iOS 9.0+
- macOS 10.11+
- Mac Catalyst 13.0+
- tvOS 9.0+
- watchOS 2.0+
- Core Data
A constraint conflict occurs when your data model is using unique constraints and one or more managed objects are violating that constraint.
When this error occurs, the error instance can be interrogated to determine which instance of
NSManaged is violating the constraint and which property on the
NSManaged instance is in violation.