Re: [Modeling-users] toOne relationship returns base class instead of subcl

[Sebastien B. <sbi...@us...>]

John Lenton <jl...@gm...> wrote:
> in the model
>=20
>      Person
>        / \
>         |
>   PhysicalPerson <---->> Address
>=20
> querying an Address for its PhysicalPerson returns Person instances,
> which was unexpected (for me, at least). Is this correct, or is it a
> bug?

If you mean that, having an address 'addr', addr.getPerson() has class
'Person', yes, this is intended, as long as addr.getPerson().isFault()
is True. As soon as you'll need an addr's person property the fault will
be fired and you'll get the correct class for addr.getPerson().


Now you may wonder why this is like this. We discussed this here:
https://sourceforge.net/mailarchive/forum.php?thread_id=3D3457563&forum_id=
=3D10674


See esp. the third post dated 2003-11-15 20:40.  While the example taken
there involves a relationship pointing from a subclass to its root
class, you'll see that you get exactly the same kind of problem if you
add a class Photo such as:      Photo <<---> Person


  Now you'll see that the discussion "ended" there with an open
  question, about if and how this could/should be changed. Time to
  rediscuss this I guess, huh?


-- S=E9bastien.


PS: BTW the interesting methods on this topic:=20

        DBChannel.fetchObject() calling DBContext.initializeObject(),
        which in particular populates the object's toOne properties with
        DBContext.faultForGlobalID().

  and this particular behaviour is tested in:=20
        test_EC_Global_Inheritance.test_02_toOneFault()