CoreData:如何正确使用migratePersistentStore创建备份副本

I'm really struggling with this. I'm trying to create a backup of my active core data base. According to Apple the best option is not to use the File Manager but the method migratePersistentStore. However I don't really understand this. I have my PersistentStoreCoordinator in my AppDelegate. So if I'm migrating the persistent store my coordinator will lose it after successfully moving it correctly? So the store is now just at the new location but not at the old anymore? So do you have any example program code for this of how my app still could keep running with the original copy?I'm really struggling with this. I'm trying to