Difference Between Code First and Database First Approach in Entity Framework Core?

Introduction

When working with Entity Framework Core (EF Core), developers often face an important decision: should they use Code First or Database First approach?

Both approaches are widely used in .NET development for building data-driven applications, but they differ in how the database and application models are created and managed.

What is Entity Framework Core?

Entity Framework Core (EF Core) is an Object-Relational Mapper (ORM) for .NET.

It helps developers:

• Work with databases using C# code

• Avoid writing complex SQL queries

• Map database tables to C# classes

This makes development faster and more maintainable.

What is Code First Approach?

In the Code First approach, you start by writing C# classes (models), and then EF Core creates the database based on those classes.

Simple meaning:
"First write code → then create database"

How It Works

1. Create model classes in C#

2. Configure DbContext

3. Use migrations to create/update database

Example

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

public class AppDbContext : DbContext
{
    public DbSet<Product> Products { get; set; }
}

Run migration:

dotnet ef migrations add InitialCreate
dotnet ef database update

EF Core will create the database automatically.

Key Features of Code First

• Database is generated from code

• Easy to modify using migrations

• Full control in developer hands

• Best for new projects

What is Database First Approach?

In the Database First approach, you start with an existing database, and EF Core generates C# classes from that database.

Simple meaning:
"First database → then generate code"

How It Works

1. Create database manually (or use existing one)

2. Use Scaffold command

3. EF Core generates models and DbContext

Example

dotnet ef dbcontext scaffold "YourConnectionString" Microsoft.EntityFrameworkCore.SqlServer -o Models

This command creates:

• Model classes

• DbContext file

Key Features of Database First

• Code is generated from database

• Useful for existing systems

• Faster when database already exists

Key Differences Between Code First and Database First