PQL requirements [Was Re: SSA-1.1]

[Patrick Dowler]

On 2011-04-29 01:35:41 Juande Santander Vela wrote:
> On 27.04.2011, at 19:19, Patrick Dowler wrote:
> >> I can, however, very well see a strong need for lenient matching.
> > 
> > This sounds exactly like material that should be considered carefully
> > enough to cover the general case, covered in a PQL specification, and
> > common to all services that accept PQL queries. Other query languages
> > (eg ADQL) have their own way of handling such things.
> 
> I was thinking exactly that when I started reading this discussion.
> 
> Is there a place in the IVOA wiki where PQL is discussed? Because I see PQL
> has a lot of advantages for a TAP-technology based archive
> backend/frontend, with SQL/ADQL not being sent, and parameters allowing
> for ranges, transformations...

I am finally getting time to plan the DAL session for Naples and would like to 
have an open discussion on this very topic (PQL requirements) plus DALI. Work 
has been on the back burner since Nara, but I think some progress on these two 
items now would help. 

On our own side (CVO) we are accumulating many use cases where the best 
solution for everyone involves PQL+TAP, but to sell it to users it would be 
nice to say "PQL works the same way in these other specialised services".

-- 

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
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Victoria (C.-B.) V9E 2M7