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 14:45:07 UTC