RegTAP 1.2 WD

[Markus Demleitner]

Dear Registry WG,

As promised at the interop, I've pushed a Working Draft of RegTAP 1.2
to the document repository: 

https://ivoa.net/documents/RegTAP/20220519/

The main motivation for 1.2 is the inclusion of the VODataService 1.2
fields for coverage in space, time, and spectrum; there is also some
more minor cleanup related to VODataService 1.2, and some items got
added inspired by pyVO's new registry interface (COALESCE,
table_name).

Finally, since nobody protested, I have indeed put in rr.tap_table I
asked about the other day
<http://mail.ivoa.net/pipermail/registry/2022-February/005483.html>.

Against the initital proposal (and against GloTS, which doesn't have
enough data for that), the table now has two identifiers, a resid for
the originating resource and a svcid for the TAP service id.  These
two are identical in the classical case of a table coming from a TAP
service.  But for tables declared in separate resources (e.g., for
VizieR's), the resid points to the specific resource describing the
table, which gives a lot more information, ranging from authors to
coverage.  The downside is that the RegTAP-typical NATURAL JOIN won't
work for rr.tap_table.  But then there is no "natural" for a table
that partily looks at the service and partly looks at a resource.

So... please have a look and see if the new features will work for
you.  And RegTAP service operators: please have a look at whether you
can implement this.  It'd be great if we could take this to PR this
year, and we'll need a second implementation by then.  Talking about
which: You should be able to try out everything mentioned in the WD
at http://dc.g-vo.org/tap.

Thanks,

         Markus