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At 12:39 PM 12/7/98 +0530, Suhas Joshi wrote:
>    Can XQL be used to query *multiple documents*? [...]

When we wrote the XQL proposal we explicitly avoided defining what it means
to query a repository of documents, but we tried not to preclude allowing
XQL to be extended to support multi-document queries.  Too many issues
arose that we didn't have time to address.

Besides, some members of the team take the point of view that XQL is not
supposed to be (or to evolve into) the complete query language.  Rather,
XQL might be used within the context of a language capable of specifying
joins, document URLs, constraints, etc.  That language might be XSL or
something like XML-QL or Lore.  Despite its name, XQL is intended to serve
only as the WHERE clause of the broader query language.

However, it should be possible to treat a document repository as a document
itself.  Virtual nodes might represent document directories whose members
are other directories or documents.  You might need to distinguish between
document root and repository root -- you'll have to define what "/." means
in the context and whether you add new functions to get to whichever entity
"/." doesn't refer to.

>[...] What format will the
>result be(result of an XQL quer is a well formed XML document ) In this
>case will the result be one document ??

How results are materialized into an XQL document are not formalized.  If
you use XQL in the context of XSL, XSL's templates will specify how the
results are materialized.  This allows you to bypass the issue of what it
means to materialize the results of the XQL query, since you can think of
the results as being nodes of the source document.

Please keep in mind that XQL is just a proposal for the W3C's XSL working
group, and that at least this member of the XSL working group intends to
live with the pattern language that the working group ultimately creates
(although we and a few other companies have "technology preview"
implementations).
--
Joe Lapp, Senior Engineer      (Looking for some good people to help
Core Technologies Team Lead     design and build new XML technologies.)
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