If it is, we throw an exception, since we don’t have a transaction to commit. We request the IDatabase from the dependency injection container through the constructor. We also declare a nullable ITransaction that will hold the current transaction until it’s committed. The following figure illustrates the code-first development workflow. The aim of the ORM is to increase the developer’s productivity by reducing the redundant task used in the application. This list is created based on the most notable features and also from frequently asked questions about Entity Framework.
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. The following figure illustrates the supported application types, advantages of entity framework .NET Frameworks and OSs. From my previous experience with Entity Framework 6, I find the generated SQL of EF Core more readable and concise. EF Core still falters around some strange edge cases, but the EF team is actively working to support more complex LINQ to SQL translations.
Seeding initial data
In the below example, we are using ADO.NET to interact with the database to fetch the data and display it in the console. Pranaya Rout is a Senior Technical Architect with more than 11 Years of Experience, Microsoft MVP, Author, YouTuber, and Blogger eager to learn new technologies. Having .NET Framework, Visual Studio, and SQL Server installed on your computer is good. In the year 2008, Microsoft introduced Entity Framework as part of .NET Framework 3.5. Currently, two latest versions of Entity Framework are available one is EF 6 (works with .NET Framework), and another is EF Core (works with .NET or .NET Core). In this Entity Framework Tutorials Course using C#, I am going to discuss all the concepts of Entity Framework with Real-Time Examples.
With Dapper, it’s a bit difficult to implement the GetEntitySet() method, since Dapper is not able to defer the evaluation of queries like Entity Framework Core. So when calling the GetEntitySet() method, Dapper will always go to the database and query the table. In a real-life scenario, this is suboptimal behavior, but this code is just for demonstration purposes. EF API will create a ForeignKey column in the table for the navigation properties that points to a PrimaryKey of another table in the database.
Entities
Now that we discussed the theory, let’s dive into an example implementation. This figure shows where the Entity Framework fits in the application. The following figure describes where the Entity Framework present in your application.
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 https://deveducation.com/ all these database related activities for your application. Sometimes this complexity increase is not justified, especially in the case of simpler applications. Let’s assume that our application is a single-user console application in a corporate intranet.
Code-First Workflow
Entity Framework introduced the Code-First approach with Entity Framework 4.1. Here, you can observe we have created the connection object, created the data adapter object, and created Dataset, Data Tables, and DataView objects. 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.
- We have achieved all this without writing a single line of ADO.NET code.
- This figure shows where the Entity Framework fits in the application.
- If it is, we throw an exception, since we don’t have a transaction to commit.
- With the unit of work pattern, we split this communication responsibility.
- This way, no database operation occurs until CommitAsync() is called.
Tables are mapped to classes and columns are mapped to class properties. Once you click on the OK button, you will be back on to the “Choose Your Data Connection” window as shown below. Once the database is ready, in the next step, create a new “Console Application” with the name EFDemo as shown in the below image. This tutorial provides a hands-on approach to the subject with step-by-step program examples that will assist you in learning and putting the acquired knowledge into practice.
EF API translates LINQ-to-Entities queries to SQL queries for relational databases using EDM and also converts results back to entity objects. In this post, we modeled an entertainment problem domain using code-first design. In addition to modeling, we applied our schema to an SQLite database. Finally, we used the expressiveness of LINQ to generate SQL queries and return our result set. By executing the command, we will build our current EF Core project and create our initial migrations. Since migrations are chronological, the prefix is an essential tool for making sense of the changes occurring to our schema.