.NET Entity Framework Core Migrations

An expert guide to mastering Entity Framework Core Migrations for effective database schema management.

Table of Contents

• Introduction
• What Are EF Core Migrations?
• Setting Up EF Core Migrations
• Creating Migrations
• Applying Migrations
• Rolling Back Migrations
• Real-World Example
• Best Practices
• Conclusion

Introduction

Entity Framework Core (EF Core) is a powerful Object-Relational Mapping (ORM) tool in .NET that helps developers work with databases using .NET objects. Migrations in EF Core provide a way to handle database schema changes over time, ensuring your database stays in sync with your application's data model.

This blog will cover everything you need to know about EF Core migrations, including how to create, apply, and manage them effectively.

What Are EF Core Migrations?

Migrations in EF Core are a way to manage schema changes in a database. They allow you to:

• Track changes in your data model.
• Apply those changes to the database incrementally.
• Rollback changes if necessary.

With EF Core migrations, you can use a Code-First Approach to design your database schema directly in your application code.

Setting Up EF Core Migrations

To get started with EF Core migrations, follow these steps:

1. Install the EF Core tools if they are not already installed:

   dotnet tool install --global dotnet-ef

2. Add the EF Core packages to your project:

   dotnet add package Microsoft.EntityFrameworkCore.SqlServer
   dotnet add package Microsoft.EntityFrameworkCore.Design

3. Ensure your DbContext is configured correctly. For example:

   
   public class AppDbContext : DbContext
   {
       public DbSet<Product> Products { get; set; }
   
       protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
       {
           optionsBuilder.UseSqlServer("YourConnectionStringHere");
       }
   }
                       

Creating Migrations

To create a new migration, use the following command:

dotnet ef migrations add InitialMigration

This will create a migration file in your project. A typical migration file includes:

• Up Method: Specifies the changes to apply to the database.
• Down Method: Specifies how to revert those changes.

Example migration file:

public partial class InitialMigration : Migration
{
    protected override void Up(MigrationBuilder migrationBuilder)
    {
        migrationBuilder.CreateTable(
            name: "Products",
            columns: table => new
            {
                Id = table.Column<int>(nullable: false)
                    .Annotation("SqlServer:Identity", "1, 1"),
                Name = table.Column<string>(nullable: false),
                Price = table.Column<decimal>(nullable: false)
            },
            constraints: table =>
            {
                table.PrimaryKey("PK_Products", x => x.Id);
            });
    }

    protected override void Down(MigrationBuilder migrationBuilder)
    {
        migrationBuilder.DropTable(name: "Products");
    }
}
            

Applying Migrations

Apply migrations to your database using the following command:

dotnet ef database update

This will execute the Up method in your migration files and apply the changes to the database.

Rolling Back Migrations

If you need to revert a migration, use the dotnet ef database update command with the migration name you want to roll back to:

dotnet ef database update InitialMigration

Real-World Example

Let's implement a real-world scenario where you create a Product table with EF Core migrations.

public class Product
{
    public int Id { get; set; }
    public string Name { get; set; }
    public decimal Price { get; set; }
}
            

After creating this model, add a migration and update the database:

dotnet ef migrations add AddProductTable
dotnet ef database update

Best Practices

• Use meaningful names for migrations.
• Test migrations in a development environment before applying them to production.
• Keep your Up and Down methods in sync.
• Commit migration files to version control.

Conclusion

EF Core migrations are a powerful tool for managing database schema changes in .NET applications. By following the steps and best practices outlined in this guide, you can ensure your database evolves alongside your application.

© 2025 Sandeep Mhaske | ayodhyya