- (void)dumpDataToConsole
{
   NSManagedObjectContext *moc = [self managedObjectContext];
   NSFetchRequest *request = [[NSFetchRequest alloc] init];
   [request setEntity:[NSEntityDescription entityForName:@"Person" 
                                  inManagedObjectContext:moc]];
   // Posortowanie pobranych osb wedug nazwiska.
   [request setSortDescriptors:[NSArray arrayWithObject:
        [NSSortDescriptor sortDescriptorWithKey:@"lastName" 
                                      ascending:YES]]];
   NSError *error = nil;
   NSArray *people = [moc executeFetchRequest:request error:&error];
   [request release];

   if (error) {
      NSLog(@"Bd podczas pobierania encji Person: %@", error);
   } else {
      for (NSManagedObject *person in people) {
         NSLog(@"Znaleziono: %@ %@", [person valueForKey:@"firstName"], 
            [person valueForKey:@"lastName"]);
      }
   }
}
