VO and ADEC identifiers

[Doug Tody]

Alberto -

Sure, I agree with this, up to a point.  Terms like "data collection",
"dataset", "catalog" etc. are fundamental concepts which we need to define
even to converse as humans.  The terms in your example below are more
precise terms needed to consistently implement queries.  These would be part
of a standard defining 1) the registry metadata and 2) the metadata used
to describe source (object) catalogs.  To do this I think one would need
to recognize that there are different types of catalogs, have a data model
for something called a source or object catalog, and ask data providers to
define a mapping from their catalog to the standard data model when the
catalog is published to the VO.  This is a lot of bite off all at once.
For now, we should start by recognizing that the registry can never hope
to understand all these things, and should rather be a mechanism we can
use to store and query information about such externally defined resources.

	- Doug


> Doug wrote:
> > ... "dataset" ... "data collection" ... "catalog"
> > This is an important issue since we strive for rigor in how we refer
> 
> > to data within the VO.
> > Perhaps we should develop a glossary of terms for VO.
> 
> Ah! Some time ago we discussed about the VO Dictionary.
> There were two people (me and Martin Hill) claiming that we
> cannot leave without it.
> 
> The basic question for me is always the same,
> how to perform the following query:
> 
>  select serviceID 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" 
> 
> without a dictionary listing all those terms in quotes ?
> 
> May I count you as the third member of the club ? :-)
>  
> Alberto
> 
> --
> Alberto Micol
> ESA/RSSD/SN-M - ST-ECF