OASIS Mailing List ArchivesView the OASIS mailing list archive below
or browse/search using MarkMail.

 


Help: OASIS Mailing Lists Help | MarkMail Help

 


 

   RE: [xml-dev] what parsers support xml schema

[ Lists Home | Date Index | Thread Index ]

Two points 
 
1.) XQuery's type system used to be based on regular tree grammars but this is no longer the case working group since they adopted W3C XML Schema as the basis of its type system. Now XQuery's data model is primarily based on named typing where the named types are W3C XML Schema types. 
 
2.) Many vendors support the W3C and W3C XML Schema including IBM, Microsoft, Altova,  Oracle, Sun, Tibco and the Excelon Corporation. These are just the companies I know off the top of my head, I'm sure if I did research I could name more. By the way, most people using SOAP, WSDL and XML web services are using W3C XML Schema directly or indirectly. 

	-----Original Message----- 
	From: Murali Mani [mailto:mani@CS.UCLA.EDU] 
	Sent: Fri 8/30/2002 12:08 PM 
	To: Maciejewski, Thomas 
	Cc: 'xml-dev@lists.xml.org' 
	Subject: Re: [xml-dev] what parsers support xml schema
	
	


	I use RELAX NG for my purposes. You can get details about RELAX NG from
	http://www.relaxng.org
	
	The following are purely my opinions, and the information I have gathered.
	
	RELAX NG is understandable and this is what academics use. RELAX NG is
	accepted in Japan as the standard, it is taught in schools in Japan,
	including the framework of regular tree grammars.
	
	The framework of regular tree grammars has found acceptance in several
	universities in US, which include University of Washington, Seattle,
	University of California, San Diego, University of California, Los
	Angeles, and University of Pennsylvania. These are the universities where
	I know there is work going on using regular tree grammars.
	
	These places have also found W3C XML Schema to be complicated and not that
	worthwhile. Further more, the processing of W3C's XQuery is based on
	regular tree grammars, though the initial typing might look as if it
	conforms to W3C XML Schema.
	
	Furthermore, there is some research at UCLA which argues that RELAX NG is
	better than W3C XML Schema for database modeling - the only thing that W3C
	XML Schema tried to solve, neglecting text modeling. Text modeling people
	use DTDs as they do not need data types to this date.
	
	It just so happens that RELAX NG came after W3C XML Schema, from the
	terrible discontent with W3C XML Schema. It is a very good schema
	language, and the design of the language is so very carefully thought of.
	The design principle can be summarized as -- collect requirements, then
	think really well about how to support them, and come up with
	mathematically elegant solutions which will support all the requirements.
	
	Who is pushing W3C XML Schema -- it seems like Oracle is one of the
	biggest pushers of this technology, the reason they say is they already
	have committed several dollars to W3C XML Schema. Even though they
	understand that RELAX NG is better than W3C XML Schema, they are finding
	it difficult to switch.
	
	I do not think such above restrictions as what Oracle faces applies to
	academic research.  Furthermore, all we will say is industries should
	slowly start supporting RELAX NG also. I am sure there will be a migration
	at some point of time, question is when..
	
	The above is as unbiased an analysis as possible of the current state of
	affairs. I will say RELAX NG is a beautiful language -- simple, elegant,
	easy to use, and applies to several application scenarios several people
	have come across.
	
	<warning>speaking for himself only</warning>
	
	cheers and regards - murali.
	
	
	-----------------------------------------------------------------
	The xml-dev list is sponsored by XML.org <http://www.xml.org>, an
	initiative of OASIS <http://www.oasis-open.org>
	
	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>
	
	





 

News | XML in Industry | Calendar | XML Registry
Marketplace | Resources | MyXML.org | Sponsors | Privacy Statement

Copyright 2001 XML.org. This site is hosted by OASIS