Understanding the Core Data Stack
Before you dive right into the project and add Core Data to it, let's take a look at how Core Data actually works, what it is, and what it isn't. In order to make efficient use of Core Data, it's essential that you know what you're working with.
When you work with Core Data, you're actually utilizing a stack of layers that starts with managed objects and ends with a data store. This is often a SQLite database, but there are different storage options you can use with Core Data, depending on your application needs. Let's take a quick look at the layers involved with Core Data and discuss their roles in an application briefly:
At the top-right of this diagram is the NSManagedObject class. When you use Core Data, this is the object you'll interact with most often since it's the base class for all Core Data models your app contains. For instance, in the app you will build in this chapter, the family member and movie models are subclasses of NSManagedObject.
Each...
