With regard to coredata storage, the operation could’t be completed. (cocoa error 133020.)



self.context=[[NSManagedObjectContext alloc] initWithConcurrencyType:NSPrivateQueueConcurrencyType];
    [self.context setPersistentStoreCoordinator:dm.PSC];
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(mocDidSaveNotification:) name:NSManagedObjectContextDidSaveNotification object:nil];
    [self.context setMergePolicy:NSMergeByPropertyObjectTrumpMergePolicy];//important!!!

 

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