EF Inheritance

inheritance ef.cs

class Program
	{
		static void Main(string[] args)
		{
			var ctx = new Testctx();

			var usr = new User() {username = "bob"};
			ctx.Users.Add(usr);
			ctx.SaveChanges();

			var susr = new SiteUser() {site = "bobsite", User = usr};
			ctx.SiteUsers.Add(susr);
			ctx.SaveChanges();

			var rusr = new RoleUser() { role = "bobrole", User = usr };
			ctx.RoleUsers.Add(rusr);
			ctx.SaveChanges();


			ctx.SaveChanges();

			var ru= ctx.RoleUsers.ToList();
		}
	}

	public class User
	{
		public int UserId { get; set; }
		public string username { get; set; }
	}
	public abstract class UserType
	{
		public virtual User User { get; set; }
		public int UserId { get; set; }
	}
	public class RoleUser : UserType
	{
		public string role { get; set; }
	}
	public class SiteUser : UserType
	{
		public string site { get; set; }
	}

	public class Testctx:DbContext
	{
		static Testctx()
		{
			Database.SetInitializer(new DropCreateDatabaseAlways<Testctx>());
		}

		public DbSet<User> Users { get; set; }
		public DbSet<SiteUser> SiteUsers { get; set; }
		public DbSet<RoleUser> RoleUsers { get; set; }

		protected override void OnModelCreating(DbModelBuilder modelBuilder)
		{
			modelBuilder.Entity<User>().HasKey(u=>u.UserId).ToTable("User");
			modelBuilder.Entity<RoleUser>().HasKey(u => u.UserId).ToTable("RoleUser");
			modelBuilder.Entity<SiteUser>().HasKey(u => u.UserId).ToTable("SiteUser");
		}

	}