Synchronizing Core Data data with External Database

Question

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?

Answer 1

All you need to do is write the logic to translate entities from one db schema to another. You can fetch objects from the server and convert them to core data objects, and fetch object from core data and convert them to mysql entities when saving to the server. Nothing too difficult involved really

Answer 2

I agree with Griffo; simply translate the rows or entities you retrieve from the mysql database into managed objects (and visa versa).

If I understand what you are looking to correctly, I would definitely recommend using Core data. Translating the data between MySQL and Core Data isn't that hard, and if you use an NSFetchedResultsController to display your data in a UITableView, you practically don't have to write any code.

Answer 3

and you can always preserve the original GUIDs as, for example, optional externalIDs for the imported entities. This way you will be able troubleshoot your data imports easier and correlated the data between the to types of the data stores.