Lists Home |
Date Index |
Thanks Michael and all who answered my question! I didn't realize
I would hit so many 'nerve endings'. Politics aside - organizations
are making business decisions based upon incomplete and/or inaccurate
Betty Harvey | Phone: 410-787-9200 FAX: 9830
Electronic Commerce Connection, Inc. |
firstname.lastname@example.org | Washington,DC SGML/XML Users Grp
URL: http://www.eccnet.com | http://www.eccnet.com/xmlug/
On Wed, 3 Jul 2002, Michael Kay wrote:
> The input to an XQuery query consists of (at compile time) a set of type
> definitions and (at run time) a set of documents/trees with type
> annotations. The set of type definitions can be empty, and the type
> annotations can be defaulted, so queries can therefore be written
> against documents that have not been subjected to schema processing.
> The XQuery working group has only recently started work on conformance
> statements. There is a draft proposal on the table that defines a
> conformance level for implementations that don't support schema
> processing - in other words, such implementations don't handle type
> definitions or type annotations. Whether this proposal makes it into the
> next draft depends more (I think) on getting the detail right than on
> any differences about the principle.
> Of course it's also possible that some vendors will want to impose
> stronger constraints, for example that all the documents in the scope of
> a single query conform to the same schema. Presumably people who don't
> like such a constraint won't buy the product...
> As far as the XQuery spec is concerned, although the type system is
> chosen to be compatible with XML Schema, there is no requirement for the
> type definitions and type annotations actually to be produced by XML
> Schema processing (just as XSLT can process a source tree that wasn't
> created by parsing source XML).
> I hope this goes some way to answering the question.
> Michael Kay
> Software AG
> home: Michael.H.Kay@ntlworld.com
> work: Michael.Kay@softwareag.com
> > -----Original Message-----
> > From: Betty Harvey [mailto:email@example.com]
> > Sent: 02 July 2002 23:51
> > To: firstname.lastname@example.org
> > Subject: [xml-dev] XQuery and DTD/Schema?
> > I haven't been following the progress of XQuery closely. I
> > was advised today that a W3C Schema had to be developed
> > instead of a DTD because XQuery only works with Schema. I
> > was skeptical that the XQuery specification would really say
> > this. However, I found what I believe to be conflicting
> > information in the XQuery specification:
> > "XQuery's type system is based on [XML Schema]. Work is in
> > progress to
> > ensure that the type systems of XQuery, the XQuery Core,
> > and XML Schema
> > are completely aligned."
> > I interpret the above statement to mean that XQuery datatypes
> > will be based upon XML Schema. I believe this statement may
> > be the reason for others thinking that an XML Schema and not
> > DTD's or RELAX NG was required in order to use XQuery.
> > Any thoughts on my interpretation of the specification. Thanks!
> > Betty
> > /\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/
> > Betty Harvey | Phone: 410-787-9200 FAX: 9830
> > Electronic Commerce Connection, Inc. |
> > email@example.com | Washington,DC SGML/XML
> > Users Grp
> > URL: http://www.eccnet.com | http://www.eccnet.com/xmlug/
> > /\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\\/\/
> > -----------------------------------------------------------------
> > The xml-dev list is sponsored by XML.org
> > <http://www.xml.org>, an initiative of OASIS
> The list archives are at http://lists.xml.org/archives/xml-dev/
> To subscribe or unsubscribe from this list use the subscription
> manager: <http://lists.xml.org/ob/adm.pl>