propertiesToFetch
A collection of either property descriptions or string property names that specify which properties should be returned by the fetch.
Declaration
var propertiesToFetch: [Any]? { get set }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 invalidArgumentException exception.
This property can be set with managedObjectResultType and thereby implement a partial faulting (whereby only some of the properties are populated) of the returned objects, as well as the dictionaryResultType to define what properties are included in the resulting NSDictionary.