Can not delete an entity from Core Data, using RestKit 0.20

Question

The code below does not delete the entity. The "delete was successful" message appears on the console so the entity is found. All other operations I use succeed.

I am using RestKit 0.20.

NSManagedObjectContext *context = [RKManagedObjectStore defaultStore].mainQueueManagedObjectContext;
NSError *error = nil;

NSFetchRequest * fetchRequest = [[NSFetchRequest alloc] init];
[fetchRequest setEntity: [NSEntityDescription entityForName:@"Auction" inManagedObjectContext:context]];
NSPredicate *predicate = [NSPredicate predicateWithFormat:@"AuctionID = %d", auctionID];
[fetchRequest setPredicate:predicate];

NSArray *result = [context executeFetchRequest:fetchRequest error:&error];
if(result.count) {
    Auction *block = result[0];
    [context deleteObject:block];
    BOOL status = [context save:&error];
    if (status == NO) {
        NSLog(@"delete falied for AuctionID:%d, error: %@", auctionID, error);
    }
    else {
        [context processPendingChanges];
        NSLog(@"delete was successful for AuctionID:%d", auctionID);

    }
}

Why might this delete operation not succeed and what is the solution to making it work.

I am using a 3rd party tool "Base" on the *.sqlite file in the simulator. I can delete entities with the tool. — zaph
I was actually wondering what the symptom of the problem is, and when you see it occur. You said you're having problem deleting data so, when are you seeing the items that you thought you had deleted? — Tom Harrington
They are not deleting,what more can I say? The data is there before the app starts, still there when the app deletes. I have deleted the *sqlite file, added the entries back with the same program and they won't delete. What I am wondering is if there is something about RestKit 0.2 that is causing some kind of lock? I am running in the 6.1 simulator. — zaph

Sebastien Sebastien · Accepted Answer · 2013-03-14T08:42:12

I found this solution :

In fact, you have to fetch datas from the persistentstore and not the current created managed context :

NSFetchRequest *fetchRequest = [NSFetchRequest fetchRequestWithEntityName:@"MyModel"];
NSSortDescriptor *descriptor = [NSSortDescriptor sortDescriptorWithKey:@"id" ascending:NO];
fetchRequest.sortDescriptors = @[descriptor];

// Setup fetched results
NSFetchedResultsController *fetchedResultsController = [[NSFetchedResultsController alloc] initWithFetchRequest:fetchRequest
                                                                        managedObjectContext:[RKManagedObjectStore defaultStore].persistentStoreManagedObjectContext
                                                                          sectionNameKeyPath:nil
                                                                                   cacheName:nil];

// AND TO DELETE A MODEL :

[[RKManagedObjectStore defaultStore].persistentStoreManagedObjectContext deleteObject:myobject];

Can not delete an entity from Core Data, using RestKit 0.20

4 Answers