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Display 100,000 items efficiently using master data

I am using NSFetchResultsController to display 100,000 + records in a UITableView. It works, but it’s SLOW, especially on iPad 1. It may take 7 seconds to download, which is torture for my users.

I would also like to be able to use partitions, but this adds at least 3 more seconds to laod time.

Here is my NSFetchResultsController:

- (NSFetchedResultsController *)fetchedResultsController {

    if (self.clientsController != nil) {
        return self.clientsController;
    }

    NSFetchRequest *request = [[NSFetchRequest alloc] init];
    NSEntityDescription *entity = [NSEntityDescription entityForName:@"Client" inManagedObjectContext:self.managedObjectContext];
    [request setEntity:entity];
    [request setPredicate:[NSPredicate predicateWithFormat:@"ManufacturerID==%@", self.manufacturerID]];
    [request setFetchBatchSize:25];

    NSSortDescriptor *sort = [[NSSortDescriptor alloc]  initWithKey:@"UDF1" ascending:YES];
    NSSortDescriptor  *sort2= [[NSSortDescriptor alloc] initWithKey:@"Name" ascending:YES];
    [request setSortDescriptors:[NSArray arrayWithObjects:sort, sort2,nil]];

    NSArray *propertiesToFetch = [[NSArray alloc] initWithObjects:@"Name", @"ManufacturerID",@"CustomerNumber",@"City", @"StateProvince",@"PostalCode",@"UDF1",@"UDF2", nil];
    [request setPropertiesToFetch:propertiesToFetch];

    self.clientsController =
    [[NSFetchedResultsController alloc] initWithFetchRequest:request
                                        managedObjectContext:self.managedObjectContext sectionNameKeyPath:nil
                                                   cacheName:nil];

    return self.clientsController;

}

I have an index on ManufacturerID that is used in my NSPredicate. This seems like a pretty simple NSFetchRequest - all I can do to speed it up? Or did I just hit the limit? Something is missing for me.

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2 answers

-: NSFetchedResultsController . .

-: , . :

  • , , .
  • , . , fetchLimit.
    • , , .
  • ​​ .
    • performBlock:
    • dispatch_async().
  • FRC reloadData.

s > 200 . .

+7

, @Mundi , . , , FRC, ManagedObjectContext. MOC , , , . cellForRowAtIndexPath :

NSManagedObject *object = [self.fetchedResultsController objectAtIndexPath:indexPath];
object = (TapCellar *)[self.managedObjectContext existingObjectWithID:[object objectID] error:nil];

, . , , , MOC, . , , MOC MOC , - :

NSPersistentStoreCoordinator *coordinator = [self persistentStoreCoordinator];
if (coordinator != nil) {
  _privateManagedObjectContext = [[NSManagedObjectContext alloc] initWithConcurrencyType:NSPrivateQueueConcurrencyType];
  [_privateManagedObjectContext setPersistentStoreCoordinator:coordinator];

  _managedObjectContext = [[NSManagedObjectContext alloc] initWithConcurrencyType:NSMainQueueConcurrencyType];
  [_managedObjectContext setParentContext:_privateManagedObjectContext];

}

, , , :

if ([self.managedObjectContext hasChanges]) {
   [self.managedObjectContext performBlockAndWait:^{
      NSError *error = nil;
      ZAssert([self.managedObjectContext save:&error], @"Error saving MOC: %@\n%@",
             [error localizedDescription], [error userInfo]);
   }];
}

, , , . 30K +, .

, , !

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