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In this example we will see how to use it in our i OS application.
First we will see how to create our data model and then how to perform the following basic operations: A data model consist of a group of entities.
Simple changes, such as attribute defaults, validation rules, and fetch request templates can be modified without consequence.
Other more structural changes require that persistent stores be migrated to new model versions.
This post is part of my collection: Swift 2 – For Beginners.
Core Data is a persistence framework provided by Apple.
Alternatively, you may download, unzip, and use the project up to this point from Core Data/Grocery Dude-After Chapter02
let context = (UIApplication.shared Application().delegate as! App Delegate).managed Object Context let person Service = Person Service(context: context) // Create let juan Carlos = person Service.create("Juan Carlos", age: 52) // Read all var people : [Person] = person All() // Read by id let first Person = person By Id(people.object ID)!In Chapter 2, “Managed Object Model Basics,” the fundamentals of managed object models were introduced, yet you were constrained to just one entity and a few attributes.The next logical step is to add more to the model; however, this requires a number of preliminary steps in order to prevent crashes caused by these changes.This chapter will show how to add model versions and model mappings, as well as demonstrate different migration techniques you can choose when upgrading a model.As an application evolves, its managed object model will probably need to change, too.