TAP: Scope and role of PQ

[Douglas Tody]

Hi All -

I wrote up a summary of the TAP param query concept and its current
status to provide a basis for discussion.  This can be found at

     http://www.ivoa.net/cgi-bin/twiki/bin/view/IVOA/TapParamQueryIssues

You can also find it under "Other Related Documents" on the main DAL
table access discussion page.

This summarizes the current state of TAP-PQ as well as identifies some
issues which could benefit from further discussion.  In particular
the topics of general data/service linking to table records and
the possible integration of the generic dataset query with TAP are
introduced, although these are too involved to cover here fully.
We can discuss these further as separate topics, and in the interop.

In looking again at the TAP param query capability I hope we can
avoid debating again those issues which have already been agreed.
Rather we should focus upon the details of what the TAP param query
will provide, discussing this among those of us who are interested
in providing this capability to our users.

 	- Doug