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What is the purpose of NSManagedObjectContext?
A managed object context is an instance of NSManagedObjectContext . Its primary responsibility is to manage a collection of managed objects. These managed objects represent an internally consistent view of one or more persistent stores.
What is NSManagedObjectContext?
An object space to manipulate and track changes to managed objects.
How do I get NSManagedObjectContext?
You could pass in your managed object context as a property of each view controller. If you have an NSManagedObject that you’re already passing around, you can get the NSManagedObjectContext from the managedObjectContext of said object.
What is NSManagedObjectContext in Core Data?
NSManagedObjectContext. The NSManagedObjectContext object manages a collection of model objects, instances of the NSManagedObject class. It is possible for an application to have multiple managed object contexts. Each managed object context is backed by a persistent store coordinator.
Is Core Data a Threadsafe?
Core Data is designed to work in a multithreaded environment. However, not every object under the Core Data framework is thread safe. To use Core Data in a multithreaded environment, ensure that: Managed object contexts are bound to the thread (queue) that they are associated with upon initialization.
What is persistent store coordinator?
A persistent store coordinator is an instance of NSPersistentStoreCoordinator . It has a reference to a managed object model that describes the entities in the store or stores it manages. The coordinator is the central object in a Core Data stack.
Is Core Data is thread safe?
Is NSManagedObjectContext thread safe?
The NSManagedObjectContext class isn’t thread safe. Plain and simple. You should never share managed object contexts between threads. This is a hard rule you shouldn’t break.
What is delete rule in Core Data?
A delete rule defines what happens when the record that owns the relationship is deleted. A delete rule defines what happens when the record that owns the relationship is deleted. Select the notes relationship of the Category entity and open the Data Model Inspector on the right.
Can the NSPersistentStoreCoordinator have more persistent stores?
Multiple persistent stores for NSPersistentStoreCoordinator The first would be the big one in the bundle, and the second could be a small one in the documents folder, storing special “favorite” entities with relationships to the big store.
When to use nsmanagedobjectcontext in core data?
In situations such as store migration, Core Data will create instances of NSManagedObjectContext for its own use. Under these circumstances, you cannot rely on any features of your custom subclass.
How are changes to managed objects tracked in context?
An object space to manipulate and track changes to managed objects. A context consists of a group of related model objects that represent an internally consistent view of one or more persistent stores. Changes to managed objects remain in memory in the associated context until Core Data saves that context to one or more persistent stores.
Which is the parent store of a managed object?
Managed object contexts have a parent store from which they retrieve data representing managed objects and through which they commit changes to managed objects. Prior to OS X v10.7 and iOS v5.0, the parent store is always a persistent store coordinator.