A Boolean value that indicates whether, when the fetch is executed, it matches against currently unsaved changes in the managed object context.
- iOS 3.0+
- macOS 10.6+
- Mac Catalyst 13.0+
- tvOS 9.0+
- watchOS 2.0+
- Core Data
This value is
true if when the fetch is executed, the fetch will match against currently unsaved changes in the managed object context; otherwise the value is
false. The default value is
If the value is
false, the fetch request doesn't check unsaved changes and only returns objects that matched the predicate in the persistent store.
A value of
true is not supported in conjunction with the result type
dictionary, including calculation of aggregate results (such as
min). For dictionaries, the array returned from the fetch reflects the current state in the persistent store, and does not take into account any pending changes, insertions, or deletions in the context.
If you need to take pending changes into account for some simple aggregations like
min, you can instead use a normal fetch request, sorted on the attribute you want, with a fetch limit of 1.