Setting up the database

If you're on Windows as I am, then your database server should already be up and running as a Windows service that starts automatically when your machine boots up. If you're on Mac/Linux, this may or may not be the case, so just ensure that the database server is running—the PostgreSQL website will have instructions on how to do this if necessary.

Creating a database context

EF Core will actually handle the creation of the database; we just need to tell it what kind of RDBMS we're using, and provide a connection string for its location and authentication credentials. Again, it doesn't really matter where we put the following files, but my preference is a Data folder for anything to do with EF setup/configuration, entity models, and seed data.

The first file we'll need to create is an EF database context class:

namespace ECommerce.Data
{
    public class EcommerceContext : IdentityDbContext<AppUser,  
    AppRole, int>
    {
        public EcommerceContext(DbContextOptions...