Go to Package Manager Console and type command help migration. Type Enable-Migrations -ContextTypeName EXPShopContext. This command creates a migration folder with InitialCreate.
What is migration in code first approach?
Code First Migrations allow you to create a new database or update an existing database based on your model classes using the Package Manager Console for running commands. If you are using the EF code first approach then there are more ways to initialize the database provided by the Entity Framework as follows.
How do I migrate to Entity Framework?
Entity Framework introduced a migration tool that automatically updates the database schema when your model changes without losing any existing data or other database objects. It uses a new database initializer called MigrateDatabaseToLatestVersion.
How do you use code first approach?
In this tutorial, you:
- Create an MVC web app.
- Set up the site style.
- Install Entity Framework 6.
- Create the data model.
- Create the database context.
- Initialize DB with test data.
- Set up EF 6 to use LocalDB.
- Create controller and views.
Which is better code first or database first?
3)Database Version Control
Versioning databases is hard, but with code first and code first migrations, it’s much more effective. Because your database schema is fully based on your code models, by version controlling your source code you’re helping to version your database.
How do you add a column in code first approach?
Run Two Commands, That’s It
- Once you run the add-migration command, a new migration class will be created and opened, in that, you can see a new column has been added to the Employee table. …
- Once add migration is done, the next step is to update the database with the new changes. …
What is lazy loading in Entity Framework?
Lazy loading is the process whereby an entity or collection of entities is automatically loaded from the database the first time that a property referring to the entity/entities is accessed. Lazy loading means delaying the loading of related data, until you specifically request for it.
What is scaffold DbContext?
Reverse engineering is the process of scaffolding entity type classes and a DbContext class based on a database schema. It can be performed using the Scaffold-DbContext command of the EF Core Package Manager Console (PMC) tools or the dotnet ef dbcontext scaffold command of the . NET Command-line Interface (CLI) tools.
How do I get rid of last migration?
Removing and Resetting Migrations
- Remove the _MigrationHistory table from the Database.
- Remove the individual migration files in your project’s Migrations folder.
- Enable-Migrations in Package Manager Console.
- Add-migration Initial in PMC.
- Comment out the code inside of the Up method in the Initial Migration.
Which command is used to run migration?
EF Migrations series
Enable-Migrations: Enables Code First Migrations in a project. Add-Migration: Scaffolds a migration script for any pending model changes. Update-Database: Applies any pending migrations to the database. Get-Migrations: Displays the migrations that have been applied to the target database.
How do you run migration?
Open the Package Manager Console from Tools → Library Package Manager → Package Manager Console and then run the enable-migrations command (make sure that the default project is the project where your context class is).
What is a code first approach?
Code-First is mainly useful in Domain Driven Design. In the Code-First approach, you focus on the domain of your application and start creating classes for your domain entity rather than design your database first and then create the classes which match your database design.
How do I connect to database in code first approach?
View -> Server Explorer
- View -> Server Explorer.
- Right click on Data Connections and select Add Connection…
- If you haven’t connected to a database from Server Explorer before you’ll need to select Microsoft SQL Server as the data source.
- Connect to either LocalDB or SQL Express, depending on which one you have installed.