separating TAP and query languages

[Patrick Dowler]

I took a quick stab at separating the param query language from the TAP spec 
and I think the result is quite clean and encouraging. I tried with normative 
text and examples to show how PQL would be used in TAP. There are some loose 
ends remaining but it is workable and gives more or less the same actual 
interface that TAP 0.31 described. 

The main change is that REQUEST no longer distinguishes the query language: 
there is one value for doing a query (imaginatively named "doQuery") and the 
3 VOSI-related request values. This remains consistent with DAL2. If the 
value of REQUEST=doQuery, then the caller must also specify LANG, which is 
where the language is set (e.g. LANG=ADQL as before, but now also LANG=PQL, 
with language version optionally embedded in the LANG value). All remaining 
parameters depend on the value of LANG.

Draft documents are posted on

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

-- 

Patrick Dowler
Tel/Tél: (250) 363-0044
Canadian Astronomy Data Centre
National Research Council Canada
5071 West Saanich Road
Victoria, BC V9E 2M7

Centre canadien de donnees astronomiques
Conseil national de recherches Canada
5071, chemin West Saanich
Victoria (C.-B.) V9E 2M7