RE: Use of Xquery with XACML

["Daniel Engovatov" <dengovatov@bea.com>]

As I am a member of W3C XQuery working group, I may try to answer.

XPath 2.0 and XQuery 1.0 (which are both still not in the last call
stage yet) are using the same underlying data model.  For most intends
and purposes XPath 2.0 is a subset of XQuery, lacking such facilities as
full FLWOR expression and element constructors.

I seriously doubt that adding those data transformation facilities will
add any value to the XACML representation, but will make it much more
cumbersome to implement and use.  We really refer to data as being
evidence - transient result of an XQuery expression does not fit well
with this notion.

It seems to me that you may achieve the result you want in a much more
straightforward way if you use some stand alone XQuery engine, such as
SAXON (http://saxon.sourceforge.net/) from Michael Kay, to construct the
resource content document.  You may then refer to the constructed data
using XPath expressions, or populate notional context using those
results.

Daniel;





-----Original Message-----
From: Muhammad Masoom Alam [mailto:Muhammad.alam@uibk.ac.at] 
Sent: Sunday, December 05, 2004 10:47 AM
To: Daniel Engovatov; xacml-dev@lists.oasis-open.org
Cc: Seth Proctor; sunxacml-discuss@lists.sourceforge.net
Subject: Use of Xquery with XACML

Dear all,

After looking at the restricted use of Xpath in XACML , i propose the
use of 
Xquery , which is much more advanced n have a alots of database SQL like

features to query to the XML documents, and it is very feasible to use 
Xquery instead of Xpath  for advance Queries in XML.

In this regard , Dear seth , do u have some knwoledge of java libraries 
about Xquery , so that they can be easily embeded into the SUN's 
implemenation ??



with Best regards.
Muhamamd.