[obs-tap]:updates on the Proposed recommendation

[Douglas Tody]

On Thu, 7 Jul 2011, Arnold Rots wrote:

> Aside from what I reported in a previous message, quoted below, there
> are more discrepancies between Table 5 and Tables 6 and 7:
>
> obs_creator_did is missing from Table 7
> o_units in Table 5 should be o_unit
> pol_states is missing from Table 6
> facility_name and instrument_name are spelled differently;
>  even though required, they show up in Table 7, rather than 6
> em_unit is missing from Table 5
> o_stat_error is missing from Table 7
>
> Also, note the comment I made on MJD in use case 1.6
> and on the uselessness of bib_reference because of its murky
> definition
>
> I still lament the fact that the data access functionality is
> compromising the self-consistency and usefulness of the data discovery
> function, but decided for our tarred packages to use:
>  dataproduct_type = NULL
>  dataproduct_subtype = package:event,image
>  access_format = application/x-tar
> As far as I can tell, this is within the specifications.

Well we don't specify what the subtypes you provide for your archive
should be so I suppose you could get away with this, but this example is
not at all what we had in mind.  The subtype should be the science type
of the specific data product, *not* details about the content of the
data product.  I would expect the type to be "event" (meaning "event
data" not "event list") and the subtype to be something more like
"chandra.hrc.package", "chandra.hrc.refimage (or "rosat.XX" etc.).

Note subtypes are supposed to be fixed strings so that one can search
the local archive for a particular type of data product; if you try to
describe what is included in a particular data product then such
selection won't be possible.  So for example a client will do a generic
query to see what subtypes Chandra defines, and then they can pose a
more specific query to get a certain type of Chandra-specific data
product.  Likewise for ALMA etc.

Note you also have obs.title where you can provide a short description
of the data product and for this you can provide whatever you want.

 	- Doug