What Is C# Entity Framework? A Comprehensive Guide

It saves the data in the database which are stored in the properties of the business entities (domain classes) and also retrieves the data from the database and converts it to business entities objects automatically. Entity Framework (EF) is an open source ORM framework for .NET applications supported by Microsoft. EF simplifies mapping between objects in your software to the tables and columns of a relational database. Entity Framework was first released in 2008, Microsoft’s primary means of interacting between .NET applications and relational databases.

Now copy and paste the following code in the main method of the program class as shown below. From our next article onwards, I am going to explain everything in detail. The Entity Framework Create Employee and Department classes automatically based on the Employees and Departments Tables. Tables are mapped to classes and columns are mapped to class properties.

The Entity Data Model

EF Core includes providers as NuGet packages which you need to install. Entity Framework Core is the new version of Entity Framework after EF 6.x. It is open-source, lightweight, extensible and a cross-platform version of Entity Framework data access technology. An ORM framework does this object to SQL mapping by generating SQL statements and the Entity manager will execute them when you need to save or load objects from the database. It comes at the cost of another abstraction layer, but it will make the code easier to write.

As you can see, there’s a many-to-many relationship between my two classes, and when I run my migration, everything goes well. I get my table A, my table B, and my table AB, which contains A_ID and B_ID. In this scenario, a different context is used to retrieve and save data. One instance of context class is used to retrieve the data, and another is used to save the data. EF API is responsible for maintaining the states of entities throughout their lifecycle. Each entity possesses a state according to the operation performed by the context class.

Our Software Development Courses Duration And Fees

Let us first see the example without using Entity Framework and then we will see the same example using Entity Framework. In the below example, we are using ADO.NET to interact with the database to fetch the data and display it in the console. Version 5.0.0 was released what is entity framework on August 11, 2012[11] and is targeted at .NET framework 4.5. Also, this version is available for .Net framework 4, but without any runtime advantages over version 4. The following figure illustrates where the Entity Framework fits into your application.

Entity Framework is an open-source ORM framework for .NET applications supported by Microsoft. It enables developers to work with data using objects of domain specific classes without focusing on the underlying database tables and columns where this data is stored. With the Entity Framework, developers can work at a higher level of abstraction when they deal with data, and can create and maintain data-oriented applications with less code compared with traditional applications.

What is Entity Framework in .NET Framework?

And here we are also writing the SQL Commands to fetch the data from the database tables and fill the dataset. We can avoid all these ADO.NET Related things if we use Entity Framework. Let us proceed and see how we can rewrite the same example using Entity Framework using C# language. In this article, I am going to give you a brief introduction to the Entity Framework. Before .NET 3.5 as a developer, we often used to write ADO.NET code to perform CRUD operations with the underlying database.

If this is not clear at this moment how it works, don’t worry we will discuss everything in detail in our upcoming articles. Please use the below SQL script to create the database EF_Demo_DB, and tables Departments and Employees, and populate the tables with sample data. This list is created based on the most notable features and also from frequently asked questions about Entity Framework. It is an enhancement to ADO.NET that gives developers an automated mechanism for accessing & storing the data in the database.

Navigation Property

But Entity Framework can do all of the above automatically for us if we provide the necessary database schema to the Entity Framework. Let us understand this step by step how to achieve the same using Entity Framework. Entity Framework is an Object-Relational Mapper which enable the .NET developers to work with the database using the .NET objects. It eliminates the need for accessing the code of the data that developers need to write. Entity Framework Core uses a provider model to access many different databases.

This tutorial is designed for those who want to learn how to start the development of the Entity Framework in their application. The aim of the ORM is to increase the developer’s productivity by reducing the redundant task used in the application. This tutorial on ‘ASP.NET Entity Framework’ covers its features and architecture. Apart from what ASP.NET Entity framework is, it also includes why to use it and its version history.

Entity Framework is an ORM and ORMs are aimed to increase the developer’s productivity by reducing the redundant task of persisting the data used in the applications. The following figure illustrates the supported application types, .NET Frameworks and OSs. Entity Framework (EF) is an open source[2] object–relational mapping (ORM) framework for ADO.NET. It was originally shipped as an integral part of .NET Framework, however starting with Entity Framework version 6.0 it has been delivered separately from the .NET Framework. There are other ORMs in the marketplace, such as NHibernate and LLBL Gen Pro. Most ORMs typically map the type of the domain directly to the schema of the database.

The entity state can be represented by an enum System.Data.Entity.EntityState in EF 6. This model is best suitable for new projects where the database does not exist. This model is stored using the EDMX file and can be viewed and edited by the developer. EF API infers INSERT, UPDATE, and DELETE commands based on the state of entities when the SaveChanges() method is called. The ChangeTrack keeps track of the states of each entity as and when an action is performed.

Basic Workflow in Entity Framework

Prior to .NET 3.5, we (developers) often used to write ADO.NET code or Enterprise Data Access Block to save or retrieve application data from the underlying database. We used to open a connection to the database, create a DataSet to fetch or submit the data to the database, convert data from the DataSet to .NET objects or vice-versa to apply business rules. Microsoft has provided a framework called “Entity Framework” to automate all these database related activities for your application. It is an entity class that does not depend on any framework-specific base class. It is the normal .NET CLR class that’s why it is named “Plain Old CLR Objects”.

• EF API translates LINQ-to-Entities queries to SQL queries for relational databases using EDM and also converts results back to entity objects.
• The entity state can be represented by an enum System.Data.Entity.EntityState in EF 6.
• It helps execute the create, read, update, and delete commands in a database schema.
• Once you click on the OK button, you will be back on to the “Choose Your Data Connection” window as shown below.