Where to find some more details on Core Data object model versioning and migration?

I just wonder what this third panel for versioning configuration is, in 开发者_JAVA百科the Xcode data modeler on the top right, third tab. Want to see some examples for what this is good for and wether or not I should already provide versioning information right from the beginning.

Any cool link and hint is appreciated.

The first thing I'd read would be Apple's Core Data Model Versioning and Data Migration Programming Guide.

You don't need to provide versioning information from your first build of an application. However, once your application has seen its first release and people are starting to use it, you will want to add versions of your data model for each time you change that model. Simple changes to the data model can be automatically migrated at startup of your application using the lightweight migration feature introduced with iPhone OS 3.0 and Snow Leopard. More complex data model changes may require setting up manual migration.