What is managed object in Core Data?

What is managed object in Core Data?

A managed object model is a set of objects that together form a blueprint describing the managed objects you use in your application. A model allows Core Data to map from records in a persistent store to managed objects that you use in your application.

What is managed object class?

A managed object is a data processing or data communications resource that may be managed through the use of an Open Systems Interconnection (OSI) management protocol. The resource itself need not be an OSI resource.

What is NSManagedObjectModel?

NSManagedObjectModel provides an API to retrieve a stored fetch request by name, and to perform variable substitution—see fetchRequestTemplate(forName:) and fetchRequestFromTemplate(withName:substitutionVariables:) . You typically define fetch request templates using the Data Model editor in Xcode.

How do you create a managed object?

Core Data

1. Build out the Core Data Model.
2. Create the Managed Object. Copy Item.swift for later use. Auto-generate Core Data subclass and extension files. Update the NSManagedObject file to include functionality from Item.swift.
3. Build the Core Data Stack.
4. Implement Saving Data.
5. Implement Fetching Data.
6. Implement Deleting Data.

How are managed objects used in core data?

A managed object model allows Core Data to map from records in a persistent store to managed objects that you use in your application. The model is a collection of entity description objects (instances of NSEntityDescription ).

What does nsmanagedobject do in core data?

At first glance, NSManagedObject instances may appear to be glorified dictionaries. All they seem to do is manage a collection of key-value pairs. It is true that the NSManagedObject class is a generic class, but it implements the fundamental behavior required for model objects in Core Data.

How to create entity description in core data?

To create an entity description, we invoke a class method on the NSEntityDescription class, entity (forEntityName:in:). We pass in the name of the entity and a managed object context. The entity name corresponds to the one defined in the data model. Why does entity (forEntityName:in:) require a NSManagedObjectContext instance?

How to define an attribute in core data model?

To define an attribute, select it in the Core Data model editor and specify values in the Attribute pane of the Core Data Model inspector; see Attribute pane in the Data Model inspector.