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我正在尝试在应用程序运行时在我的应用程序中实现备份/恢复系统。我创建了数据库的备份并将其放入 Backups 文件夹中。如果我想恢复，我删除我的持久存储，删除原始文件，复制备份并重新连接。我下面的代码有效。我的问题是，我这样做正确吗？我所做的事情是否有任何风险？感谢您对我的代码的任何反馈：

- (BOOL)resetApplicationModel {

    // ----------------------
    // This method removes all traces of the Core Data store and then resets the application defaults
    // ----------------------

    NSError *_error = nil;
    NSURL *_storeURL = [[self applicationDocumentsDirectory] URLByAppendingPathComponent:@"Database.sqlite"];

    NSPersistentStore *_store = [persistentStoreCoordinator persistentStoreForURL:_storeURL];

    // Remove the SQL store and the file associated with it
    if ([persistentStoreCoordinator removePersistentStore:_store error:&_error]){
        [[NSFileManager defaultManager] removeItemAtPath:_storeURL.path error:&_error];
    }

    if (_error) {
        NSLog(@"Failed to remove persistent store: %@", [_error localizedDescription]);
        return NO;
    }

    [persistentStoreCoordinator release], persistentStoreCoordinator = nil;
    [managedObjectContext release], managedObjectContext = nil;

    NSString *applicationDocumentDirectory = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0];
    NSString *originalFile = [applicationDocumentDirectory stringByAppendingPathComponent:@"Database.sqlite"];

    NSString *backupDatabaseFolder = [applicationDocumentDirectory stringByAppendingPathComponent:@"Backups"];
    NSString *backupFile = [backupDatabaseFolder stringByAppendingPathComponent:[NSString stringWithFormat:@"DatabaseBackup.sqlite"]];

    [[NSFileManager defaultManager] copyItemAtPath:backupFile toPath:originalFile error:nil];

    // Rebuild the application's managed object context
    rootViewController.managedObjectContext = nil;
    rootViewController.managedObjectContext = self.managedObjectContext;

    return YES;
}
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