*IVOA DAL WG Running Meeting #4
Wednesday 30 September 2020 - 20:00 UTC - vconf

Participants: (8) Aitor Ibarra, Brent Miszalski, James Dempsey, Jesus Salgado, Mark Taylor, Patrick Dowler, François Bonnarel, Marco Molinaro

*Agenda:
	1. - ProvTAP
	2. - ObjVisSAP
	3. - November Interop & DAL
*
*Notes
*1 - ProvTAP
ProvTAP - a data discovery mechanism based on the provenance associated with the data
Demonstrated ADQL based queries - 4 tables in the query
Internal draft available on the DAL wiki pages
Current author discussion is around the output, how to make quering easier, how to integrate with other PROV tools
Feedback from DAL chairs, ESCAPE has requested simplification or denormalisation
Solutions:
    * Merge descriptions into their parent entities
    * A single entity using pre-defined joins
    * Keep full provtap schema and propose views - can these become the simplified schema?
[PD] Views by themselves are interesting - could see these implemented on top of CAOM for example
[MT] Should this be a DM standard? [FB] It affects both and most authors are heavily involved in DM too.

*2 - ObjVisSAP
Standardise the interface to query when a facility can see an object
Parameter based query - 3 mandatory params plus some optional params
Working draft being uploaded to GitHub
Recent workshop has had a lot of observatory interest and feedback which will result in updates
A couple of service implementations exist, a new one was implemented by a ground based observatory in a week
Also talking with radio observatories to identify their unique requirements

https://www.cosmos.esa.int/web/vovisobs_protocols/home - overview
http://integral.esa.int/toby/ - web based client

*3 - Interop discussion
For each session will have two options - an hour on a topic or two with in depth discusison, or a mixed sesson with four short talks
Call for contributions will go out in the net week or so
So if you want a longer discussion please contact Marco and/or James
LIkely to be ~16 slots in total, aiming for 3 DAL or DAL joint slots
Schedule page: https://wiki.ivoa.net/twiki/bin/view/IVOA/InterOpNov2020
[AI] Would like to discuss ObjVisSAP - partial session