Core Data Programming Guide Notes -- Part 6

This is the notes of Core Data Programing Guide from reading Apple's document

reference: http://developer.apple.com/library/ios/#DOCUMENTATION/Cocoa/Conceptual/CoreData/cdProgrammingGuide.html#//apple_ref/doc/uid/TP30001200-SW1

Core Data FAQ
Where does a Managed Object Context Come From? 

Where a managed object context comes from is entirely application-dependent. In a Cocoa document-based application using NSPersistentDocument, the persistent document typically creates the context, and gives you access to it through the managedObjectContext method. 

How do I initialize a store with default data? 

There are two issues here: creating the data, and ensuring the data is imported only once.

There are several ways to create the data.

• You can create a separate persistent store that contains the default data and include the store as an application resource. When you want to use it, you must either copy the whole store to a suitable location, or copy the objects from the defaults store to an existing store.
• For small datasets, you can create the managed objects directly in code.
• You can create a property list—or some other file-based representation—of the data, and store it as an application resource. When you want to use it, you must open the file and parse the representation to create managed objects. 

How do I use my existing SQLite database with Core Data?

You don’t. Although Core Data supports SQLite as one of its persistent store types, the database format is private. You cannot create a SQLite database using native SQLite API and use it directly with Core Data (nor should you manipulate an existing Core Data SQLite store using native SQLite API). If you have an existing SQLite database, you need to import it into a Core Data store


 How do I fetch objects in the same order I created them?

 Objects in a persistent store are unordered. Typically you should impose order at the controller or view layer, based on an attribute such as creation date. If there is order inherent in your data, you need to explicitly model that.