I am having a Core Data problem with `NSFetchedResultsController`. I have a one to many relationship between a parent and child entity. The array in the `childFetchedResults.fetchedObjects` property is NOT sorted by `number` (number is an int32 property in the model). It doesn't seem to matter if I use the `MagicalRecord` convenience category methods or not.

```
NSFetchRequest *req = [Child MR_requestAllSortedBy:@"number" ascending:YES withPredicate:[NSPredicate predicateWithFormat:@"parent = %@", self.parent]];
childFetchedResults = [[NSFetchedResultsController alloc] initWithFetchRequest:req managedObjectContext:[NSManagedObjectContext MR_defaultContext] sectionNameKeyPath:nil cacheName:nil];
childFetchedResults.delegate = self;
NSError *error;
[childFetchedResults performFetch:&error];
NSLog(@"fetched objects: %@", childFetchedResults.fetchedObjects);

```

However, if I sort the array of fetched objects using the exact same sort descriptor, it works fine: 

```
NSLog(@"fetched objects: %@", [childFetchedResults.fetchedObjects sortedArrayUsingDescriptors:[NSArray arrayWithObject:[NSSortDescriptor sortDescriptorWithKey:@"number" ascending:YES]]]);

```

I gather you can only use comparators which Core Data can pass on to the SQLite store when specifying sort descriptors for a fetch request. But I feel like that shouldn't matter in this case since sorting by a number has got to be supported by SQLite.

Anyone solved this? I feel like it's a similar issue to the one described here: [NSSortDescriptor not being called](https://stackoverflow.com/questions/10109115/nssortdescriptor-not-being-called).

As for `MR_requestAllSortedBy`, it's in `MagicalRecord`, here is the implementation:

```
+ (NSFetchRequest *) MR_requestAllSortedBy:(NSString *)sortTerm ascending:(BOOL)ascending inContext:(NSManagedObjectContext *)context
{
    NSFetchRequest *request = [self MR_requestAllInContext:context];

    NSSortDescriptor *sortBy = [[NSSortDescriptor alloc] initWithKey:sortTerm ascending:ascending];
    [request setSortDescriptors:[NSArray arrayWithObject:sortBy]];

    return request;
}

```