[EF] Initialize database with data using Code First

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Introduction

This article is a part of a series of articles I write about Entity Framework Code First. You can find my previous article here:

• Entity Framework Code First: Let's Try It 
• EF Code First: Add a Foreign Key relationship 
• EF Data Annotations and Code Fluent  

Now, if we know how to create a database using Code First, we could want to add some data during the database creation in order to have some useful data to test our interface. We can write a SQL script that will provide data in the database but EF Code First allows us to do it in an easy way, so let's try it. 

Using the code

The data would be defined in an initializer class:

public class EfInitializer : DropCreateDatabaseIfModelChanges<MyContext>
{
    protected override void Seed(MyContext context)
    {
        var persons = new List<Person>
                {
                    new Person {LastName = "Smith", FirstName = "John", BirthDate= DateTime.Now.AddDays(-1080)},
                    new Person {LastName = "Doe", FirstName = "James", BirthDate= DateTime.Now.AddDays(-1070)}
                };
                                
        persons.ForEach(p => context.Persons.Add(p));
                                
        var projects = new List<Project>
                {
                    new Project {Name = "Project 1", Manager = persons[0]},
                    new Project {Name = "Project 2", Manager = persons[0]},
                    new Project {Name = "Project 3", Manager = persons[1]}
                };
        projects.ForEach(p => context.Projects.Add(p));
        
        context.SaveChanges();
    }
}

Once the data has been defined, we have to tell our context to initialize the database with our data. To do that, go in the Program.cs class and add the following line in the Main method:

Database.SetInitializer<MyContext>(new EfInitializer());

This line is really simple to understand. We are telling our database to use the class EfInitializer to initialize itself. Now you can run your console application and see that data is added to the database at startup. First we run the program:

Everything went fine. Let's see our database:

Good news: Our data is there!!!

Hope this will help you during your development.

History

• June, 2012: First post.
• June, 2012: Updated the post with links to my previous articles