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PONSManagedContext takes very long time to persist
 

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    <p>My application has a UITableViewController which has a list of cells representing names of cities. When a user clicks a cell, the application will change the cell accessoryType to UITableViewCellAccessoryCheckmark and save the text value of the cell (city name) into the persisted store. However, I found that every time I click the cell, it requires at least 10 seconds to actually store the data into the Persistent Store. Any idea why this happens? Instead of saving the data immediately, why it takes so long to persist?</p> <pre><code>- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath { NSString *cityName = [self.citySettingModel nameOfCityAtIndex:indexPath.row OfCountryAtIndex:self.countryIndex]; UITableViewCell *cell = [tableView cellForRowAtIndexPath:indexPath]; if (cell.accessoryType == UITableViewCellAccessoryCheckmark) { cell.accessoryType = UITableViewCellAccessoryNone; [[self.citySettingModel worldbikesCoreService] removeCity:cityName]; } else { cell.accessoryType = UITableViewCellAccessoryCheckmark; [[self.citySettingModel worldbikesCoreService] addCity:cityName toCountry:self.countryName]; } } </code></pre> <p>The code for create a City and Country objects are in a different class</p> <pre><code>- (City *) addCity:(NSString*) cityName toCountry:(NSString*) countryName { NSManagedObjectContext *context = [self.delegate managedObjectContext]; Country *country = [self.countryDAO addCountry:countryName inManagedObjectContext:context]; City *city = [self.cityDAO addCity:cityName inManagedObjectContext:context]; [country addCitiesObject:city]; return city; } - (City*) addCity:(NSString*) cityName inManagedObjectContext:(NSManagedObjectContext *)context { NSFetchRequest *fetchRequest = [NSFetchRequest fetchRequestWithEntityName:@"City"]; fetchRequest.predicate = [NSPredicate predicateWithFormat:@"cityName = %@", cityName]; NSSortDescriptor *sortDescriptor = [NSSortDescriptor sortDescriptorWithKey:@"cityName" ascending:YES]; fetchRequest.sortDescriptors = [NSArray arrayWithObject:sortDescriptor]; NSError *error; NSArray *matches = [context executeFetchRequest:fetchRequest error:&amp;error]; if (error) NSLog(@"error when retrieving city entities %@", error); City *city; if (!matches || [matches count] &gt; 1) ; else if ([matches count] == 0) { city = [NSEntityDescription insertNewObjectForEntityForName:@"City" inManagedObjectContext:context]; city.cityName = cityName; } else city = [matches lastObject]; return city; } </code></pre>
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    1. COFirst: where do you actually save the context in the code above? I don't see any saving happening here. Second: Don't you think that your fetchrequest in addCity:... might be responsible for those 10 seconds...?
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