At 06:05 AM 11/5/2004, Mike Taylor wrote:
> > Date: Fri, 5 Nov 2004 05:22:20 -0500
> > From: Eliot Christian <[log in to unmask]>
> > I am wondering about the rules on inheriting from one context set to
> > another.
>A clarification: there is NO "inheritance" of context sets. This
>paradigm is a holdover from Z39.50 version 2, when all the attributes
>in a Type-1 query had to be taken from the same attribute set, with
>ugly results such as the GILS and CIMI sets both importing BIB-1
>wholesale. But in Z39.50 version 3, and of course in SRW/U, there is
>no such limitation: indexes from different context sets can be freely
>mixed, so there should ideally be _no_ duplication of indexes between
The word "inheriting" may have been a poor choice. In the GILS Context
Set I would like to re-use some indexes defined in other context sets,
as a deliberate strategy to enhance interoperability. (GEO and BIO
will, in turn, re-use some indexes from GILS and perhaps so will UDDI,
ebXML and others).
A specific example occurs with "dc.creator" (and I do acknowledge
the alias "dc.author"). Its definition in the GILS context is:
The name of the originator of the information resource.
Note: originator is defined as "The agent, whether person
or organization, responsible for all or portions of the
The DC context set doesn't provide a definition, but the DCMI site
defines Creator in version 1.1 as: "An entity primarily responsible
for making the content of the resource."
In effect, I have overloaded the DC semantics to move the emphasis
away from "Who gets the creative credit for this?" toward the sense
of "Who stands behind this?". (I think this reflects the difference
between an academic and information publishing orientation versus
a legalistic and information compiling orientation.) My question is:
Is such unilateral overloading permissible from the CQL perspective?
>And now, on to your specific query:
> > For instance, the index named "identifier" occurs in the Record
> > Metadata http://srw.cheshire3.org/contextSets/rec/1.1/ as "A unique
> > local identifier for the record within the current context". This
> > is quite general and similar to Dublin Core, where it is defined as
> > "An unambiguous reference to the resource within a given context."
>Aha -- not quite! The Dublin Core identifier element is the
>identifier of the resource you're describing, whereas the Rec set's
>identifier is that of the record that's describing it.
Understood. But, in both cases the semantics of "identifier" specifies
that it is application is "within the current context". So, Rec could
use "dc.identifier" rather than creating "rec.identifier". (And, BTW,
I also need "identifier" in GILS and I don't know which one to use.)