EF5 Inheritance with code first - ef-code-first

Question

I've multiple smaller versions of classes that maps to single database table
e.g
UserBrief Class:
[Table("Users")]
public partial class UserBrief
{
[Key]
public int EmployeeID { get; set; }
public string FirstName { get; set; }
public string LastName { get; set; }
}
UserAdmin Class
[Table("Users")]
public partial class UserAdmin : UserBrief
{
public int RoleID { get; set; }
}
UserHR Class
[Table("Users")]
public partial class UserHR : UserBrief
{
public string EmailAddress { get; set; }
public string Phone { get; set; }
}
User Class
[Table("Users")]
public partial class User
{
[Key]
public int EmployeeID { get; set; }
public string FirstName { get; set; }
public string LastName { get; set; }
public int RoleID { get; set; }
public string EmailAddress { get; set; }
public string Phone { get; set; }
}
I've multiple bounded contexts. Depending on functionality of context I've used above classes.
If I add single class in context and Ignore all other classes then it works fine.
e.g
public DbSet<UserHR> UserHRs { get; set; }
protected override void OnModelCreating(System.Data.Entity.DbModelBuilder modelBuilder)
{
modelBuilder.Ignore<UserBrief>();
modelBuilder.Ignore<UserAdmin >();
modelBuilder.Ignore<User>();
}
Now if I added UserBrief and UserHRs
It gives error "Invalid column name 'Discriminator'" as EF assumes that this is Table per Hierarchy (TPH) approach.
I've been searching for solution, but can't find how to do this.
Any ideas?
Thanks in advance.

Answer 1

The inherited classes in the POCO objects for the TPH approach should represent sub-types of the class, not just property sections. Having the User table which is a combination of UserHR and UserAdmin breaks this representation.
You could attempt to add a Discriminator property to the User table to fix the error, but I would suggest either just using the Users table with nullable properties or modeling your objects as 1-to-1 relationships:
public class UserBrief
{
[Key]
public int EmployeeID { get; set; }
public string FirstName { get; set; }
public string LastName { get; set; }
public virtual UserAdmin UserAdmin { get; set; }
public virtual UserHR UserHR { get; set; }
}
public class UserAdmin
{
[Key]
[ForeignKey("UserBrief")]
public int EmployeeID { get; set; }
public int RoleID { get; set; }
public virtual UserBrief UserBrief{ get; set; }
}
public class UserHR
{
[Key]
[ForeignKey("UserBrief")]
public int EmployeeID { get; set; }
public string EmailAddress { get; set; }
public string Phone { get; set; }
public virtual UserBrief UserBrief{ get; set; }
}