RE: catching up on DASL/WebDAV

> I think there are two separate questions here... one is about RDF and
> one is about XML.  Although RDF can be serialized in XML, the sorts of
> queries people are doing today with RDF query languages are over the
> abstract graph, not over the XML representation.

Agreed.

> For XML documents, and resources that present themselves as XML, one
> might reasonably consider using XML Query.

XQuery certainly would be my choice for XML query language. But, even once
you've settled on XQuery, there are a number of protocol issues that would
need to be addressed. For example, can clients ask that responses not exceed
a particular size? Are query responses resources, with a URI, and how long
can that URI be dereferenced? How should query errors be passed back to the
client?

> It turns out there are lots of fairly complex things one might
> reasonably want to ask about the contents of XML Documents, so
> perhaps it's not surprising that XML Query is a rather large
> specification.  I wouldn't expect all DAV implementations to support
> it, even in XML environments.

True, although there is a growing class of DAV servers that sit on top of
XML databases, and so are interested in this capability.

> So maybe this is an area where technical experimentation is needed
> before any standardization is considered.

Never hurts. I'm seeing some experimentation among DASL implementors
already.

> We could go to the XML Query Working Group and see if there is consensus
> on any such technical work; my personal expectation is that they are too
> busy right now to focus on such issues, just because of where they are
> in their editing cycle, but that this may well change by January.

This timeframe is probably right on. I think if things got rolling early to
middle of next year, that would be fine. Inaction on this does have
opportunity costs, but they're still fairly low.

- Jim