Entity Framework Core Add-Migration References Code First - http://www.entityframeworktutorial.net/efcore/entity-framework-core-console-application.aspx Migrations Commands Add-Migration Creates a migration script analysing changes since the previous model. No modification is done to database.After generation you can edit the UP and Down from the Migration object. Install the Package Manager Console tools by running the following command in Package Manager Console: PowerShell Install-Package Microsoft.EntityFrameworkCore.Tools Update the tools by running the following command in Package Manager Console.PowerShell Update-Package Microsoft.EntityFrameworkCore.Tools Create Database Schema In Visual Studio, open NuGet Package Manager Console from Tools -> NuGet Package Manager -> Package Manager Console Check if you are on the correct project : and enter the following command: PM> add-migration CreateSchoolDB After creating a migration, we still need to create the database using the update-database command in the Package Manager Console, as below. PM> update-database –verbose DBContext DbContext Methods Method Usage Add Adds a new entity to DbContext with Added state and starts tracking it. This new entity data will be inserted into the database when SaveChanges() is called. AddAsync Asynchronous method for adding a new entity to DbContext with Added state and starts tracking it. This new entity data will be inserted into the database when SaveChangesAsync() is called. AddRange Adds a collection of new entities to DbContext with Added state and starts tracking it. This new entity data will be inserted into the database when SaveChanges() is called. AddRangeAsync Asynchronous method for adding a collection of new entities which will be saved on SaveChangesAsync(). Attach Attaches a new or existing entity to DbContext with Unchanged state and starts tracking it. AttachRange Attaches a collection of new or existing entities to DbContext with Unchanged state and starts tracking it. Entry Gets an EntityEntry for the given entity. The entry provides access to change tracking information and operations for the entity. Find Finds an entity with the given primary key values. FindAsync Asynchronous method for finding an entity with the given primary key values. Remove Sets Deleted state to the specified entity which will delete the data when SaveChanges() is called. RemoveRange Sets Deleted state to a collection of entities which will delete the data in a single DB round trip when SaveChanges() is called. SaveChanges Execute INSERT, UPDATE or DELETE command to the database for the entities with Added, Modified or Deleted state. SaveChangesAsync Asynchronous method of SaveChanges() Set Creates a DbSet that can be used to query and save instances of TEntity. Update Attaches disconnected entity with Modified state and start tracking it. The data will be saved when SaveChagnes() is called. UpdateRange Attaches a collection of disconnected entities with Modified state and start tracking it. The data will be saved when SaveChagnes() is called. OnConfiguring Override this method to configure the database (and other options) to be used for this context. This method is called for each instance of the context that is created. OnModelCreating Override this method to further configure the model that was discovered by convention from the entity types exposed in DbSet properties on your derived context. DbContext Properties Method Usage ChangeTracker Provides access to information and operations for entity instances this context is tracking. Database Provides access to database related information and operations for this context. Model Returns the metadata about the shape of entities, the relationships between them, and how they map to the database. Scaffold Database (PostGres) Créer un projet C# ASP Net Core Il faut ajouter le Nuget correspondant à Postgres dans le projet avec les commandes suivantes Install-Package Microsoft.EntityFrameworkCore.Design Install-Package Npgsql.EntityFrameworkCore.PostgreSQL Installing the tools dotnet ef can be installed as either a global or local tool. Most developers prefer installing dotnet ef as a global tool using the following command: .NET Core CLI dotnet tool install --global dotnet-ef To use it as a local tool, restore the dependencies of a project that declares it as a tooling dependency using a tool manifest file. Update the tool using the following command: .NET Core CLI dotnet tool update --global dotnet-ef Verify installation Run the following commands to verify that EF Core CLI tools are correctly installed: .NET Core CLI dotnet ef The output from the command identifies the version of the tools in use: Output _/\__ ---==/ \\ ___ ___ |. \|\ | __|| __| | ) \\\ | _| | _| \_/ | //|\\ |___||_| / \\\/\\ Entity Framework Core .NET Command-line Tools 2.1.3-rtm-32065 dotnet ef dbcontext scaffold "Server=localhost;Database=Test;Username=postgres;Password=password" Npgsql.EntityFrameworkCore.PostgreSQL -o Models Ajouter Postgres dans Projet ASP Net Core Installer les Packages Nuget Il faut ajouter le Nuget correspondant à Postgres dans le projet avec les commandes suivantes Install-Package Microsoft.EntityFrameworkCore.Design Install-Package Npgsql.EntityFrameworkCore.PostgreSQL Vérifier que l'on a un DBContext Il faut au moins un model qui dérive de DBContext nécessaire. public partial class PEActionContext : DbContext { public PEActionContext() { } public PEActionContext(DbContextOptions options) : base(options) { } public virtual DbSet Agences { get; set; } ..... etc En ajoutant un DbSet on rends la table disponible. Fichier Startup.cs Dans la méthode ConfigureServices ajouter : services.AddDbContext(options => options.UseNpgsql( @$"Server={Configuration["DBHost"]};Port=5432;Database={Configuration["DBDatabase"]};Username={Configuration["DBAdmin"]};Password={Configuration["DBPassword"]}") ); Cela rajoute au moteur d'injection le DbContext pour qu'il puisse ensuite être utilisé dans le code. Pour l'utiliser depuis un Controller Il faut pour cela initialiser le constructeur du Controller avec l'objet DBContext correspondant, dans notre exemple PEActionContext que nous avons déclaré dans le service de Startup.cs Si le contructeur n'exite pas on le crée avec pour paramètre un objet de type PEActionContext . C'est le moteur d'injection de ASP Net Core qui se chargera de créer l'instance de l'objet dans le paramètre du constructeur. [Route("api/[controller]")] public class AgencesController : ControllerBase { private PEActionDbContext _peActionDbContext; public AgencesController(PEActionDbContext peActionDbContext) { _peActionDbContext = peActionDbContext; }