On macOS 10.4+ and iOS 3.0+, an instance of NSFetchRequest describes the search criteria used to retrieve data from a persistent store. It is a class in the Apple Core Data Framework.
From the NSFetchRequest documentation:
An instance of NSFetchRequest collects the criteria needed to select and optionally to sort a group of managed objects held in a persistent store. (See NSPersistentStore and NSManagedObject.) A fetch request must contain an entity description (an instance of NSEntityDescription) or an entity name that specifies which entity to search. It frequently also contains
A predicate (an instance of NSPredicate) that specifies which properties to filter by and the constraints on selection, for example, “last name begins with a ‘J’”. If you don’t specify a predicate, then all instances of the specified entity are selected (subject to other constraints; see executeFetchRequest:error: for full details).
An array of sort descriptors (instances of NSSortDescriptor) that specify how the returned objects should be ordered, for example, by last name then by first name.
Questions related to this can also be tagged with core-data.
NSFetchRequest objects can be used with the method executeFetchRequest:error:, defined by NSManagedObjectContext.
Sample syntax:
NSFetchRequest *request = [[NSFetchRequest alloc] init];
NSEntityDescription *entity = [NSEntityDescription entityForName:@"Employee"
inManagedObjectContext:managedObjectContext];
[request setEntity:entity];
