Fluent NHibernate entity HasMany collections of different subclass types

Question

So everything is working well with the basic discriminator mapping. I can interact directly with entities A and B without any problems.

public class BaseType {}
         


        

Answer 1

You mapping looks odd, in particular I think it should look more like this

DiscriminateSubClassesOnColumn<string>("Type")
               .SubClass<EntityA>("A", m => { })
               .SubClass<EntityB>("B", m => { });

Having said that it seems that method is depreciated and you should instead define the following (taken from Automapping Subclasses:

public class ParentMap : ClassMap<Parent>
{
  public ParentMap()
  {
    Id(x => x.Id);
    Map(x => x.Name);

    DiscriminateSubClassesOnColumn("type");
  }
}

public class ChildMap : SubclassMap<Child>
{
  public ChildMap()
  {
    Map(x => x.AnotherProperty);
  }
} 

Not sure this will fix it though, I am yet to encounter your scenario.

Edit: The issue is also raised here, sounding more like a bug to me