Entity Framework 4 - Code First not storing inherited table separate from base table

With EF Code First CTP 4 I've created a simple project. This project consists of 2 classes, one inherited from other.

I wish to store the data in separate tables, but the default of EF 4 is to map/store these two entities in the same table.

With .ToTable(), I can change this behavior, but with this I have a side effect: when I persist a Inherited object, EF doesn't persist the common values (ex. Id) on the base class.

I'm sure I'm leaving to s开发者_C百科et some information in the mapping but do not know which.

static void Main(string[] args)
{
    Database.SetInitializer<ZooContext>(new RecreateDatabaseIfModelChanges<ZooContext>());
    using (ZooContext ctx = new ZooContext())
    {
        Mammal mam = new Mammal() ;
        mam.NumberOfLegs = 4;
        ctx.Animals.Add(mam);
        // ctx.Mammals.Add(mam)  as the same behavior
        ctx.SaveChanges();
    }
}


public class ZooContext : DbContext
{   
    public DbSet<Animal> Animals { get; set; }
    public DbSet<Mammal> Mammals { get; set; }

    protected override void OnModelCreating(System.Data.Entity.ModelConfiguration.ModelBuilder modelBuilder)
    {
        modelBuilder.Entity<Animal>().HasKey(p => p.Id).
                                    MapHierarchy().
                                    Case<Animal>(a => new { a.Id });
        modelBuilder.Entity<Animal>().HasKey(p => p.Id).
                                    MapHierarchy().
                                    Case<Mammal>(a => new { a.Id, a.NumberOfLegs }).ToTable("Mammals");

        base.OnModelCreating(modelBuilder);
    }
}

public class Animal
{
    public virtual int Id { get; set; }
}

public class Mammal : Animal
{
    public int NumberOfLegs { get; set; }
}

Don't really know about CTP4, but in CTP5 this can be done using .Map(x=>x.ToTable("TableName")) here is example of what you want:

public class Mammal
{
    public int Id { get; set; }
    public string Name { get; set; }
}

public class Animal : Mammal
{
    public int NumberOfLegs { get; set; }
}

public class ZooContext : DbContext
{
    public DbSet<Mammal> Mammals { get; set; }
    public DbSet<Animal> Animals { get; set; }

    protected override void OnModelCreating(ModelBuilder builder)
    {
        builder.Entity<Mammal>()
            .Map<Animal>(x => x.ToTable("Animals"))
            .Map<Mammal>(x => x.ToTable("Mammals"));

        base.OnModelCreating(builder);
    }
} 

class Program
{
    static void Main()
    {
        DbDatabase.SetInitializer(new DropCreateDatabaseIfModelChanges<ZooContext>());

        using (var ents = new ZooContext())
        {
            ents.Mammals.Add(new Animal { Name = "First Mutant Animal", NumberOfLegs = 10 });
            ents.Mammals.Add(new Mammal { Name = "First Mammal" });
            ents.Mammals.Add(new Mammal { Name = "Second Mammal" });
            ents.SaveChanges();
        }
    }
}

PS: I used SqlCe 4.0 as database engine. This fails to start, if Mammal class has only Id and no other properties (Don't know why). So I added Name property base class. I'm not sure weather it is problem in CTP4, SqlCe 4.0, or I just don't know something.

Hope this helps.