Instance Property

propertiesToFetch

A collection of either property descriptions or string property names that specify which properties should be returned by the fetch.

Declaration

@property(nonatomic, copy) NSArray *propertiesToFetch;

Discussion

Property descriptions can either be instances of NSPropertyDescription or NSString. The property descriptions may represent attributes, to-one relationships, or expressions. The name of an attribute or relationship description must match the name of a description on the fetch request’s entity.

Special Considerations

You must set the entity for the fetch request before setting this value; otherwise, NSFetchRequest throws an NSInvalidArgumentException exception.

This property can be set with NSManagedObjectResultType and thereby implement a partial faulting (whereby only some of the properties are populated) of the returned objects, as well as the NSDictionaryResultType to define what properties are included in the resulting NSDictionary.

See Also

Managing How Results Are Returned

resultType

The result type of the fetch request.

includesPendingChanges

A Boolean value that indicates whether, when the fetch is executed, it matches against currently unsaved changes in the managed object context.

returnsDistinctResults

A Boolean value that indicates whether the fetch request returns only distinct values for the fields specified by propertiesToFetch.

includesPropertyValues

A Boolean value that indicates whether, when the fetch is executed, property data is obtained from the persistent store.

shouldRefreshRefetchedObjects

A Boolean value that indicates whether the property values of fetched objects will be updated with the current values in the persistent store.

returnsObjectsAsFaults

A Boolean value that indicates whether the objects resulting from a fetch request are faults.

NSFetchRequestResultType

Constants that specify the possible result types a fetch request can return.

NSFetchRequestResult

An abstract protocol used with parameterized fetch requests.