Core data executeFetchRequest returns NSManagedObject

Question

In Core data, I have three types of entities. Entity A, Entity B, Entity C

Entity C to entity A is a one to many relationship. Entity C to entity B is also a one to many relationship.

In another word, Both A and B has an inRecord field which points to a single instance of Entity C.

I have the following code

    NSFetchRequest *request = [NSFetchRequest fetchRequestWithEntityName:@"EntityA"];

    request.predicate = [NSPredicate predicateWithFormat:@"inRecord.title = %@", title];
    NSSortDescriptor *sortDescriptor = [NSSortDescriptor sortDescriptorWithKey:@"date" ascending:YES];
    request.sortDescriptors = [NSArray arrayWithObject:sortDescriptor];

    NSError *error = nil;
    NSArray *arrayOfEntity = [context executeFetchRequest:request error:&error];

Now if I check the class of arrayOfEntity[0], it will say it is of class EntityA. However, with the exact same code, if I replaced EntityA by EntityB above, if I check the class of arrayOfEntity[0], it does not say EntityA, instead, it says it is class NSManagedObject.

Why is that?

Have you checked in the Core Data Model inspector if the "Class" of "EntityB" is set to "EntityB"? — Martin R

Martin R Martin R · Accepted Answer · 2013-09-08T07:51:12

You have to set the "Class" of the entity in the Core Data Model inspector to your managed object subclass.

(The class is set automatically if you create a custom class for the entity with "Editor -> Create Managed Object Subclass ..." from the Xcode menu.)

Core data executeFetchRequest returns NSManagedObject

1 Answers