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What is Core Data model?
Core Data uses a schema called a managed object model — an instance of NSManagedObjectModel . In general, the richer the model, the better Core Data is able to support your application. A managed object model allows Core Data to map from records in a persistent store to managed objects that you use in your application.
What is an entity in Core Data?
An entity is represented by an instance of the NSEntityDescription class. This class provides access to a wide range of properties, such as its name, the data model it is defined in, and the name of the class the entity is represented by.
How do I create a Core Data model?
Choose File > New > File and select the iOS platform tab. Scroll down to the Core Data section, select Data Model, and click Next. Name your model file, select its group and targets, and click Create.
What is core data used for?
Core Data is a framework that you use to manage the model layer objects in your application. It provides generalized and automated solutions to common tasks associated with object life cycle and object graph management, including persistence.
Where is core data stored?
The location that makes the most sense is the Documents directory. This directory is used to store data that is generated by the user and some of that data is most likely stored in the persistent store of your application.
What is a Core Data relationship?
A relationship specifies the entity, or the parent entity, of the objects at the destination. This entity can be the same as the entity at the source (a reflexive relationship). Relationships do not have to reference a single entity type.
What is fetched property in Core Data?
Fetched Properties in Core Data are properties that return an array value from a predicate. A fetched property predicate is a Core Data query that evaluates to an array of results.
What are the attributes of a core data entity?
Core Data really shines when you start working with relationships between entities. Let’s see how this works by adding a second entity named Address. The Address entity has four attributes of type String , street , number , city, and country.
How are managed objects used in core data?
In general, the richer the model, the better Core Data is able to support your application. A managed object model allows Core Data to map from records in a persistent store to managed objects that you use in your application. The model is a collection of entity description objects (instances of NSEntityDescription ).
Are there any data models in core data?
Core Data has support for many common data types like integers, floats, booleans, and so on. However, by default, the data model editor generates these attributes as NSNumber properties in the managed object subclasses.
How to create a core data entity in Xcode?
A Core Data entity encapsulates quite a bit of information. Let me show you what that information looks like. Open Xcode and create a new project based on the Single View Application template in the iOS > Application section. Name the project CoreData, set Language to Swift, and check Use Core Data at the bottom.