[xquery-talk] Schema in xquery

Liam R E Quin liam at w3.org
Mon Mar 5 23:20:47 PST 2012

On Tue, 2012-03-06 at 02:27 +0000, David Lee wrote:
> I've been contemplating the relationship between schema and type in
> schema aware xquery.
> Is xquery strictly tied to XSD? That is,  could an implementation
> support another schema format such as rng to provide for the type
> system?  Without conversion to XSD?   Is validation strictly bound to
> type assignment?

Lots of questions here.

Anything that produces XDM instances is fine, and in fact XSD is not
tied to XDM either.

Validation is the mechanism in XQuery to get type annotations onto
nodes, but this does not preclude the use of a DTD, or of some other
validation mechanism than XSD.

I asked James Clark and Murata-san a similar question. The answer seems
to be that RNG doesn't do the *deterministic* type assignment that you
need to get the annotations working. But it could be done in principle.

The term "validation" is indeed overloaded to include "see if you can
assign types to these nodes or not".


Liam Quin - XML Activity Lead, W3C, http://www.w3.org/People/Quin/
Pictures from old books: http://fromoldbooks.org/

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