I have started working on an iPhone application that where I need to synchronize data with an external MySQL database. The current database scheme uses GUID/UUID fields as primary keys to maintain relationships between tables. I already have this working between a database app and the MySQL database, so this isn't a question regarding synchronization per say.
I've started going down the path of using Core Data, but I'm realizing that it maintains relationships between entities using it's own schema within the SQLite database.
Am I going down the wrong path using Core Data? If not how does one synchronize data between a Core Data store and an external database and still maintain the data relationships?