gistfile1.cs

  public partial class OrdersContext : DbContext
    {
        static OrdersContext()
        {
            Database.SetInitializer<OrdersContext>(null);
        }

        public OrdersContext()
            : base("Name=ToyContext")
        {
        }

        public DbSet<Order> Orders { get; set; }
        public DbSet<Person> Person { get; set; }
        
        protected override void OnModelCreating(DbModelBuilder modelBuilder)
        {
            modelBuilder.Configurations.Add(new OrderMap());
            modelBuilder.Configurations.Add(new PersonWithOrderMap());
        }
    }

    public partial class PreferencesContext : DbContext
    {
        static PreferencesContext()
        {
            Database.SetInitializer<PreferencesContext>(null);
        }

        public PreferencesContext()
            : base("Name=ToyContext")
        {
        }

        public DbSet<Person> Person { get; set; }
        public DbSet<Preference> Preferences { get; set; }

        protected override void OnModelCreating(DbModelBuilder modelBuilder)
        {
            modelBuilder.Configurations.Add(new PersonWithPreferenceMap());
            modelBuilder.Configurations.Add(new PreferenceMap());
        }
    }