出货后在CoreData应用程序中引入iCloud，如何迁移旧数据

I am planning to ship a CoreData application, but I am unsure if introducing iCloud functionality. This question come after I have been beta testing my app on iPhone, filling it with relevant data. I then added iCloud functionality and start testing on iPad. I discovered that only new entry were sync between devices, this are the tentatives I did:I am planning to ship a CoreData application, b