Re: Enforcing IDs in XML Schema

Simon,

If there is an element which is the parent element of both the
definition   element information items
and the
use_definition    element information items,
you could specify identity-definition constraints as part of the element
definition, specfically you could specify "key" and "keyref".

See section 5.2 "Keys and their references" in the W3C XML Schema Part 0:
Primer -
http://www.w3.org/TR/xmlschema-0/#specifying%20Keys&theirRefs

Bob Schloss
XML/XSL Transformational Systems - Extensible Technologies
IBM Thomas J Watson Research Center
Yorktown Heights, New York, USA
http://www.research.ibm.com/people/s/bschloss




                                                                           
             "Simon Kampa"                                                 
             <simon.kampa@stas                                             
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             uest@w3.org                                                   
                                                                   Subject 
                                       Enforcing IDs in XML Schema         
             04/30/2004 06:04                                              
             AM                                                            
                                                                           
                                                                           
                                                                           
                                                                           






Hi,

I would like to use XML Schema to enforce something like the following:

<definition id="12345">
 ...
</definition>

<use_definitions>
  <def ref="12345"/>
  ...
</use_definitions>


So, if an ID is used as a reference in the <def> element, there HAS TO
BE a correpsonding <definition> element with the same ID. Is it possible
to do this in XML Schema? Ideas?

Thanks.

--
Simon

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Received on Monday, 3 May 2004 13:49:19 UTC