vo-dml in votable

[Gerard Lemson]

Dear all

During the VO-DML-in-VOTable discussion at the last interop we decided to go
with (something like) proposal 4 on the wiki at
https://volute.googlecode.com/svn/trunk/projects/dm/vo-dml/doc/samples/votab
le/VOTable_Prop4.xml  Other options can be found in the same folder.
What we now need is to finalize the design for the XML tag(s) to add to
VOTable.
I have created a mockup of an XML schema with a complexType definition
reflecting the new element.
The design used in proposal 4 above is represented by proposal 4a in the
schema. It has attributes for role and actual type, and elements for
alternative types. Proposals 4b and 4c vary on this theme. All use a
simpleType definition reflecting the model-prefix+':'+vodml-id pattern used
to refer to VO-DML elements. See the mapping document for more detailed
descriptions (taking into account the fact that that document will have to
be updated with the choice to be made here).

Note, I am not making statements on whether these two types must be in the
VOTable targetnamespace. Andreas had some thoughts on this that I hope he
will send to the list in reply.

And obviously the final design may differ from these proposals if necessary,
but let's please converge on an acceptable design soon so Omar and I can
update the mapping document.

Cheers
Gerard