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    <p>I had this same issue, this is what I figured out, and how I resolved it.</p> <p>Magical Record has a root <code>NSManagedObjectContext</code> as a parent of the default <code>NSManagedObjectContext</code>. When I create an <code>NSFetchedResultsController</code> in the default context, everything seems to work fine, just like you. </p> <p>The problem is that all the <em>new</em> <code>NSManagedObject</code>'s come back with their still-temporary <code>ObjectID</code>'s. So, in my case, I was using an <code>NSPredicate</code> to scope a query on an associated table. I didn't just call the association method because I didn't want to load <em>everything</em> into memory and wanted <code>NSFetchedResultsController</code> to handle changes, for me. </p> <p>With the temporary <code>ObjectID</code> the query finds zero results and that's exactly what it displays.</p> <p>Apparently the child context (default) doesn't get the benefit of the transformation to non-temporary ID's, even though it's been persisted to the backing store.</p> <p>Even worse badness happened when I tried to force the issue with <code>obtainPermanentIDsForObjects:error:</code>. Core Data complained that it could not satisfy a fault for my instance. Nevermind, there's no way it was actually a fault. Simply refreshing the object had no effect, either. I suspect this is a Core Data bug that hardly no one tickles because they just use the association methods to get an NSSet.</p> <p>My fix was to use the parent context for the <code>NSFetchedResultsController</code>, just like in this question, <a href="https://stackoverflow.com/questions/10974713/magical-record-saving-and-nsfetchedresultscontroller">Magical Record, saving, and NSFetchedResultsController</a>.</p> <p>I was already wrapping the default in a new child context upon edit and, therefore, copying the instances into that editing context with <code>createInContext</code>, so I didn't have to do any extra work beyond just adding <code>.parentContext</code> to the argument.</p> <p>Incidentally, this only ever happened on new instances of the source of the association. Once an instance was there from startup, it had a non-temporary <code>ObjectID</code> and never had the issue.</p>
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    1. COSorry I think I missed something. Your advice is to create the "resources" using the "currentContext.parentContext"?
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      1. USFabiano Francesconi
    2. CONot quite, that's what I pass to the Magical Record fetch* method. Object creation (and modification) takes place in a child context with MR_defaultContext with it's parent.
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    3. COExample code, [Model fetchAllSortedBy:@"qqq" ascending:NO withPredicate:predicate groupBy:@"qqq" delegate:self inContext:self.managedObjectContext.parentContext]; In this case, self.managedObjectContext is the same as MR_defaultContext.
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