RE: XML Schema

I am not sure I understand your question but I will try and answer it.
I think you want to define a document or a root element within which
element x may occur at least once and at most an unbounded number of
times.
Clearly, this is straightforward.

Then you want to impose a constraint that at least one occurrence of
element
x must have a specified attribute value.  This is an example of what are
sometimes called co-occurrence constraints.  Such constraints cannot be
defined using XML Schema. 

All the best, Ashok 
===========================================================
Ashok Malhotra              <mailto: ashokma@microsoft.com> 
Microsoft Corporation




-----Original Message-----
From: caroline.schappler@bnpparibas.com
[mailto:caroline.schappler@bnpparibas.com] 
Sent: Monday, November 26, 2001 9:56 AM
To: castor-dev@exolab.org; xmlschema-dev@w3.org
Subject: XML Schema

Hi,

I would like to know if it is possible with XML schema to define a
constraint as described below :
I defined an element (x) which has a maxOccurs attribute to a value =
unbounded, and I have a validation rule
which define the existence of at least one instance of the element (x)I
describe above, with a specific value of one
of its attribute (y= "specific value").
How is it possible to achieve this kind of constraint using Xml schema?

For example :

<?xml version ...>
<xsd:element ref="x" maxOccurs="unbounded"/>
....
  <xsd:element name="x">
    <xsd:complexType>
      <xsd:sequence>
        <xsd:element ref="y"/>
        .....
      </xsd:sequence>
    </xsd:complexType>
  </xsd:element>
.....


Thanks for your help



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Received on Monday, 26 November 2001 15:45:38 UTC