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    <p>1 - Yes. It is possible. When you create your mapping file, make sure you change the relationship's type from an NSSet to an NSArray, like so:</p> <pre><code> @class Tags @interface Entity : NSManagedObject ... @property (nonatomic, retain) NSOrderedSet *tags; ... @end @interface Entity (CoreDataGeneratedAccessors) ... - (void)addEntityTags:(NSOrderedSet *)values; - (void)removeEntityTags:(NSOrderedSet *)values; ... @end </code></pre> <p>Change to:</p> <pre><code> @class Tags @interface Entity : NSManagedObject ... @property (nonatomic, retain) NSArray *tags; ... @end @interface Entity (CoreDataGeneratedAccessors) ... - (void)addEntityTags:(NSArray *)values; - (void)removeEntityTags:(NSArray *)values; ... @end </code></pre> <p>2 - You can specify a sort descriptor when creating your fetch request, like so:</p> <pre><code> NSFetchRequest *fetchRequest [NSFetchRequest new]; NSEntityDescription *entity = [NSEntityDescription entityForName:@"Entity" inManagedObjectContext:myManagedObjectContext]; [fetchRequest.setEntity: entity]; [fetchRequest setSortDescriptors:[NSArray arrayWithObject:[NSSortDescriptor sortDescriptorWithKey:@"tags" ascending:&lt;YES|NO&gt;]]; [fetchRequest setPredicate:[NSPredicate predicateWithFormat:@"ANY tags == %@", yyy]]; NSFetchResultsController *myFetchResultsController = [[NSFetchedResultsController alloc] initWithFetchRequest:fetchRequest managedObjectContext:myManagedObjectContext setcionNameKeyPath:nil cacheName:nil]; myFetchResultsController.delegate = self; [fetchRequest release]; // Forget that if using ARC. NSError *error = nil; if (![myFetchResultsController performFetch:&amp;error]) { NSLog(@"Failed to fetch data: %@", error); } </code></pre> <p>3 - If you use the property, you shouldn't need to specify a predicate for your tags. If you want to further sort your tags, you can simply use a sort descriptor on that array, like this:</p> <pre><code> NSSortDescriptor *tagDescriptor = [NSSortDescriptor sortDescriptorWithKey:@"&lt;tags field to sort on&gt;" ascending:&lt;YES|NO&gt;]; NSArray *sortedTags = [tagsProperty sortedArrayUsingDescriptors:[NSArray arrayWithObject:descriptors]]; </code></pre> <p>You can simply read from that property for your tags.</p> <p>Hope this helps!</p>
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    1. POHow to use Coredata ordered relationships with NSFetchedResultsController
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    1. USSimon Germain
    1. USSimon Germain
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    1. COThanks a lot. I will try that. Why is it required to change NSSet to NSArray? Btw its NSOrderedSet for ordered relationship. Is that what you meant? An Item can have many tags and thats why I do not want to use keypath to fetch all objects in one go.
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    2. COI always use an NSArray anyway so I can apply a sort descriptor to it if necessary. It doesn't take anything away. I think the NSOrderedSet will keep the order in which the tags were inserted in CoreData (not sure about that though). CoreData always fetches faulted relationships. It will resolve the relationship as soon as you try to access the data. Don't worry about loading ALL the objects at once.
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    3. COAnother question: Why did the following predicate did not work: [NSPredicate predicateWithFormat:@"ANY tags == %@", yyy]; This one worked: but I think it is less efficient: [NSPredicate predicateWithFormat:@"ANY tags.tagID == %@", xxx];
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