How to save data when using one ManagedObjectContext and PersistentStoreCoordinator with two stores

Question

STATEMENT OF THE PROBLEM

When I try to save a record in the read / write repository, which is one of two SQLite repositories assigned to the same PersistentStoreCoordinator, my iPhone application crashes. One of the obvious problems when saving a record - PersistentStoreCoordinator does not know in which store to save data (just because I do not know how to do it).

First I will provide a big picture to make sure my approach sounds. Then I will provide implementation details.

BACKGROUND

This is a simplified example that introduces key aspects of the real application I'm working on.

Seed data

User input script

CURRENT IMPLEMENTATION

Implementation of Master Data

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- (NSPersistentStoreCoordinator*)persistentStoreCoordinator {
   if (_persistentStoreCoordinator == nil) {
       NSArray *bundles = @[[NSBundle bundleForClass:[self class]]];
       _persistentStoreCoordinator = [[NSPersistentStoreCoordinator alloc] initWithManagedObjectModel:[NSManagedObjectModel mergedModelFromBundles:bundles]];

       NSError *error;
       //--------------------------------------------------
       // Set options for the USER DATA Persistent Store.
       NSDictionary *options = @{NSMigratePersistentStoresAutomaticallyOption : @YES,
                                       NSInferMappingModelAutomaticallyOption : @YES};
       //--------------------------------------------------
       // Add the USER DATA Store to the Persistent Store Coordinator.
       NSPersistentStore *persistentStore = [_persistentStoreCoordinator addPersistentStoreWithType:NSSQLiteStoreType
                                                                                   configuration:nil
                                                                                             URL:self.persistentStorePathForUserData
                                                                                         options:options
                                                                                           error:&error];
       //--------------------------------------------------
       // Set options for the SEED DATA Persistent Store.
       options = @{NSMigratePersistentStoresAutomaticallyOption : @YES,
                         NSInferMappingModelAutomaticallyOption : @YES,
                                NSReadOnlyPersistentStoreOption : @YES};
       //--------------------------------------------------
       // Add the SEED DATA Store to the Persistent Store Coordinator.
       persistentStore = [_persistentStoreCoordinator addPersistentStoreWithType:NSSQLiteStoreType
                                                                configuration:nil
                                                                          URL:self.persistentStorePathForSeedData
                                                                      options:options
                                                                        error:&error];
   }
   return _persistentStoreCoordinator;
}

:

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RESEARCH

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Answer 1

Ray Wenderlich, Mic Pringle, Mic , , . .

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2) SeedData - r , App Bundle.

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Answer 2

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• addPersistentStore NSPersistentStore.

• :

  NSManagedObject *newObject = [NSEntityDescription insertNewObjectForEntityForName:@"Vehicle" inManagedObjectContext:self.managedObjectContext];
  [self.managedObjectContext assignObject:newObject toPersistentStore:userEditableStore];
  

  , assignObject:toPersistentStore: .

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