I'm a new iPhone developer (of about 4 months or so) who is starting to look at Core Data.
In the "Beginning iPhone 3 Development" book by Dave Mark it mentions that the main difference between fetched properties and relationships is that fetched properties allow lazy loading. However, I have seen other resources and accepted answers on this site which suggest that relationships do allow lazy loading.
For example, if I have a Department object with a to-many relationship with Employee then I would not want a fetch on a given Department to load all the associated employees into memory.
I would be extremely grateful for an authoritative answer on this point, and on the other differences, as it has obvious implications on any design.
Also, I would be extremely grateful if someone could point me towards a reasonable Core Data resource that is a clear and beginner friendly guide (I have been a Java Developer previously but I am new to the iPhone-Way...