Re: Using UCDs as tags

From: Alberto Micol <Alberto.Micol-at-eso.org>
Date: Wed, 13 Aug 2003 17:54:31 +0200

Thanks Roy for your answer regarding (Subject: Re: handling metadata with multiple values )

>From your answer one may read that it is the existing XML technology the one driving here,
while, obviously, it should be the IVOA requirements the ones making us decide which tools and languages we want to use.

A couple of thousand of terms are not a huge thing, of course if the language one uses is creating 1000 classes the question is: is the idea wrong or the implemention ?

I'd like to have your opinion on how to solve the sort of sql statement I put at the end of my previous email:

Select

   service_name, service_description, service_rowcount from

   Registry
where

   service_category = "CATALOG BROSWER"
   and data_class = "OBJECT CATALOG"
   and subject = "GALAXY"
   and querable_parameter = "GALAXY DISTANCE"    and output_parameter = "GALAXY NAME"

How would you make it work without a dictionary ?

Answering to Martin (Subject: Using UCDs as tags),

> The thing with us humans using the term 'WFPC2' is that we automatically
> expand it into the full meaning (or the relevent useful bits) in our heads -
> but a computer needs to have all this meaning written down somewhere, and
> inside the tags seems to be the right place to have it.
>

and Roy:

> We are trying to work towards a semantic net/ontology point of view. We
> recognize that any astronomical measurement is specified by more than just a
> UCD-type single word, but rather a host of meanings, reasons, and
> connections. Further these may have different significances to different
> people, to different applications.
>

I was thinking to have WFPC2 in the dictionary, meaning that you'll find all the related necessary information (or at least a pointer to the relevant wfpc2 data model) in the dictionary, without having to carry it along all the time.

Alberto Received on 2003-08-13Z17:54:46