Global Variable

NSErrorMergePolicy

Default policy for all managed object contexts.

Declaration

id NSErrorMergePolicy;

Discussion

This is the default policy for all managed object contexts.

In the case of failure, the save method returns with an error with a userInfo dictionary that contains the object IDs of the objects that had conflicts (NSInsertedObjectsKey, NSUpdatedObjectsKey).

See Also

Policies

NSMergeByPropertyStoreTrumpMergePolicy

A policy that merges conflicts between the persistent store's version of the object and the current in-memory version by individual property, with the in-memory changes trumping external changes.

NSMergeByPropertyObjectTrumpMergePolicy

A policy that merges conflicts between the persistent store's version of the object and the current in-memory version by individual property, with the external changes trumping in-memory changes.

NSOverwriteMergePolicy

A policy that merges conflicts between the persistent store's version of the object and the current in-memory version by pushing the entire in-memory object to the persistent store.

NSRollbackMergePolicy

A policy that merges conflicts between the persistent store's version of the object and the current in-memory version by discarding all state for the changed objects in conflict.

NSMergePolicyType

Constants that define merge policy types.

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