regarding ALTTYPE [was RE: vo-dml in votable]

[Laurent MICHEL]

Hello everybody,

Reading the last threads I do not see any formal constraint on the 
modeling space enclosed into the VO-DML serialization.
I may have missed something, but I'm understanding that VO-DML is not 
only intended to carry the mapping of VO models in DAL responses but 
that it should support any sort of DMs,

I think that clarifying this point could help contributors (myself at 
least) to both figure out what are the stakes of this open though a 
little bit obscure discussion about ALTTYPEs and to have an idea about 
where to put the cursor between the completeness of the VODML 
specification and a short term issue of a first recommendation usable by 
both client and service implementers.

For instance, it is clear that considering models as abstract entities 
which are not particularly related to some specific background will lead 
us to tackle with all OO facets whereas limiting the scope of the 
considered DMs to some composition or derivation of already defined VO 
quantities could allow significant simplification in the serialization 
process.

Joining the discussion very late and being not a guru, I hope not to be 
too much naive =:)

Bye
Laurent

NOTE: Something went wrong with this mail, This mail has been sent 3 
times on APPs in addition with a draft, but not on DM/DAL.
Sorry

Le 16/03/2015 15:49, Mark Taylor a écrit :
> On Mon, 16 Mar 2015, gerard.lemson at gmail wrote:
>
>>>        The important point is to keep the changes in VOTABLE as minimal and
>> rare
>>> as possible. I agree that the debate between "unique Types" / "multiple
>> Types" is
>>> still open and should be arbitrated by experience with VO-DML-aware
>> clients
>>> and prototypes.
>>>        In these conditions and after considering all options I finally
>> follow Mark's
>>> proposal.
>>>        This will allow some kind of experimental flexibility, freeze
>> VOTABLE changes
>>> rather soon and allow changes in VO-DML detailed syntax to be tuned in the
>>> coming monthes/years.
>> I am starting to come back a bit on what I thought Mark was proposing. I do
>> not know for sure whether we can guarantee that any proposed VOTable change
>> can be frozen until we have more progress on the mapping document itself. I
>> think I can guarantee that all annotation will be confined to VODML elements
>> on some VOTable types, but the precise details of this element may still
>> have to change a bit. In particular, simply setting maxOccurs=unbounded on
>> VODML/TYPE, though a useful step, may not be the end of the discussion.
>
> If that's the case, I'm not sure I'm so keen on my proposal either.
>
> --
> Mark Taylor   Astronomical Programmer   Physics, Bristol University, UK
> m.b.taylor at bris.ac.uk +44-117-9288776  http://www.star.bris.ac.uk/~mbt/
>

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