NorthwindSlimContext.cs

public class NorthwindSlimContext : DbContext
{
    public NorthwindSlimContext(DbContextOptions<NorthwindSlimContext> options) : base(options) { }

    public DbSet<Category> Categories { get; set; }
    public DbSet<Customer> Customers { get; set; }
    public DbSet<Order> Orders { get; set; }
    public DbSet<OrderDetail> OrderDetails { get; set; }
    public DbSet<Product> Products { get; set; }
}