实体框架代码优先-每个类型的表继承-插入问题？

public abstract class EntityBase<T> 
{   
    private T _id;       
    [Key]
    public T ID    
    {       
         // get and set details ommitted.   
    }
}
public abstract class PersonBase<T> : EntityBase<T>
{   
    // Details ommited.  
}

public class Applicant : PersonBase<int>
{   
    // Details ommitted for brevity.  
}

public class Employee : Applicant {}   

protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
     base.OnModelCreating(modelBuilder);                
     // Set up table per type object mapping for the Visitor Hierarchy.       
     modelBuilder.Entity<Employee>().ToTable(\"Employees\");
} 

public void PersistCreationOf(T entity)
{     
    DataContextFactory.GetDataContext().Set(typeof(T)).Add(entity);
}