What are faults in Core Data?

In Core Data, faults are placeholders, or “unrealized objects”. They are small objects which refer to other NSManagedObjects, which are fetched into memory only as needed. This faulting mechanism is designed to enhance performance and reduce memory use.

What is NSManagedObjectContext?

An object space to manipulate and track changes to managed objects.

How do I update my Core Data entity?

To update a specific object you need to set up a NSFetchRequest . This class is equivalent to a SELECT statetement in SQL language. The array results contains all the managed objects contained within the sqlite file. If you want to grab a specific object (or more objects) you need to use a predicate with that request.

How many types of Core Data are there?

Python Data Types are mainly of 3 types: Boolean, integer, and string. These may also be called the core data types in Python.

How do you create relationships in Core Data?

The first to-many relationship goes from the first entity (the source entity) to the second entity (the destination). The second to-many relationship goes from the second entity (the original destination entity) to the first entity (the original source entity). You then set each to be the inverse of the other.

What is the purpose of NSManagedObjectContext?

A managed object context is an instance of NSManagedObjectContext . Its primary responsibility is to manage a collection of managed objects. These managed objects represent an internally consistent view of one or more persistent stores.

How can I tell if Core Data is empty?

To check if the Core Database is empty you have to make a NSFetchRequest on the entity you want to check, and check if the results of the request are empty.

What is difference between Core Data and SQLite in iOS?

The most important difference between Core Data and SQLite is that SQLite is a database while Core Data is not. Core Data can use SQLite as its persistent store, but the framework itself is not a database. Core Data is not a database. Core Data is a framework for managing an object graph.

Is core data == SQLite?

Core Data can use SQLite as its persistent store, but the framework itself is not a database. Core Data is not a database. Core Data is a framework for managing an object graph.

What are the characteristics of core data?

What Is Core Data?

  • Change tracking and built-in management of undo and redo beyond basic text editing.
  • Maintenance of change propagation, including maintaining the consistency of relationships among objects.

How does faulting work in core data programming?

Faulting allows Core Data to put boundaries on the object graph. Because a fault is not realized, a managed object fault consumes less memory, and managed objects related to a fault are not required to be represented in memory at all. To illustrate, consider an application that allows a user to fetch and edit details about a single employee.

What does a core data fault in Xcode mean?

As you can see in the console, Core Data fetches the values of every property of the note with the exception of relationships. Notice that the value of the tags property is missing. Instead, Xcode displays relationship fault. This means that the tags of the note haven’t been fetched yet.

Why does core data not check newly inserted objects?

Core Data does not do this check on newly inserted objects because they could not have existed in any other scope. They haven’t been written to the database yet. Cause: You may have forced a newly inserted object to lose its inserted status and then changed or deleted it.

What should I do if I have a problem with core data?

Remedy: Discard this object by removing all references to it. Details: This problem can occur in at least two situations: First situation: You started with a strong reference to a managed object from another object in your application. You deleted the managed object through the managed object context. You saved changes on the object context.