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copied!<p>Currently I have a solution for that, but not a clean one:<br> I want to batch unfault by groups of 20, in an ordered relationship.</p> <p>So, every time i address an index that its index divides by 20 (index % 20 == 0), I use a new NSFetchRequest for the next 20 and unfault them by calling a common field name.</p> <pre><code>- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath { if (indexPath.row % 20 == 0) { NSArray *objectsToUnfault = [[someObject.orderedRelationship array] subarrayWithRange:NSMakeRange(indexPath.row, MIN(20, [someObject.orderedRelationship count] - indexPath.row))]; // It's important to hold on this array, otherwise objects fault back self.lastPrefetch = [self preFetchEntityOfClass:[Post class] faultObjects:objectsToUnfault error:&error]; } //... continue and create cell } - (NSArray *)preFetchEntityOfClass:(Class)entityClass faultObjects:(NSArray*)objects error:(NSError **)error { NSEntityDescription *entityDescription = [NSEntityDescription entityForName:NSStringFromClass(entityClass) inManagedObjectContext:self.managedObjectContext]; NSPredicate *predicate = [NSPredicate predicateWithFormat:@"SELF in %@", objects]; NSFetchRequest *request = [[NSFetchRequest alloc] init]; [request setEntity:entityDescription]; [request setPredicate:predicate]; [request setFetchBatchSize:MIN([objects count], 20)]; NSArray *results = [self.managedObjectContext executeFetchRequest:request error:error]; // I assume all my objects has this field "uid" NSArray *resultsUid = [results valueForKey:@"uid"]; //Batch unfaulting (results is a BatchFaultArray, private class type) if ([resultsUid count] != [results count]) { NSLog(@"Error: wrong count of uids"); //We need to use resultsUid, to avoid compiler opt } return results; } </code></pre>

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