Obscore 1.1 Erratum 3: Drop obs_id non-NULL requirement

[BONNAREL FRANCOIS]

Hi Markus,
Le 07/07/2022 à 13:37, Markus Demleitner a écrit :
> Hi François,
>
> Can I ask back on this:
>
> On Thu, Jul 07, 2022 at 10:40:01AM +0200, BONNAREL FRANCOIS wrote:
>> Something like
>>
>> "select obs_id, string_agg(obs_publisher_did, ',') as publish_did_list from
>> obscore group by obs_id"
>>
>> Then parsing publish_did_list to build the Dalink url
>> https://Organisation/dl-root?ID=...&ID=...&ID=...
> Sure -- but how does this depend on requiring obs_id to be non-NULL
> in all services?  The worst that would happen with this query if we
> don't is that all the "single" observations end up in one aggregate
> with obs_id NULL, no?
Probably yes.
>    If you see a major problem in that, could you
> elaborate?

This is breaking all observation related queries into two very different 
ones. I find this ugly, and increasing complexity for the users.

By the way , ESO Obstap service has obs_id for all their datasets. For 
images, Each observation has the image and the mesurements datasets.

CADC also has obs_id everywhere. Apparently all of theme has a 1 to 1 
remaitionship observation/dataset. They use the free syntax obs_id 
string  to build the ivi identifier obs_publisher_did string

Cheers

François

>           -- Markus