Moving Homepwner to Core Data
Your Homepwner application currently uses archiving to save and reload its data. For a moderately sized object model (say, fewer than 1000 objects), this is fine. As your object model gets larger, however, you will want to be able to do incremental fetches and updates, and Core Data can do this.
The model file
In a relational database, we have something called a table. A table represents some type; you can have a table of people, a table of a credit card purchases, or a table of real-estate listings. Each table has a number of columns to hold pieces of information about that thing. A table that represents people might have columns for the person’s last name, date of birth, and height. Every ...