- From: Tim Hanson <Timothy.Hanson@bea.com>
- Date: Thu, 14 Aug 2003 06:48:53 -0700
- To: W3C XML Schema Comments list <www-xml-schema-comments@w3.org>
If an element selected by the field of an identity constraint has
xsi:nil='true', is the value treated as missing? For example, is the
following instance valid, given the schema.
I think this should be valid since the xsi:nil attribute on the uid
elements would be equivalent to the elements missing for the purposes of
identity constraints. Either way 3.11.4 of Schema part 1 could use some
clarification around xsi:nil.
Tim
schema
------
<?xml version="1.0"?>
<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema">
<xsd:element name="root">
<xsd:complexType>
<xsd:sequence>
<xsd:element ref="uid"
maxOccurs="unbounded"/>
</xsd:sequence>
</xsd:complexType>
<xsd:unique id="foo123" name="uuid">
<xsd:selector xpath=".//uid"/>
<xsd:field xpath="."/>
</xsd:unique>
</xsd:element>
<xsd:element name="uid" nillable="true" type="xsd:anySimpleType"/>
</xsd:schema>
instance
--------
<?xml version="1.0"?>
<root xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:xsd="http://www.w3.org/2001/XMLSchema"
xsi:noNamespaceSchemaLocation="idF018.xsd">
<uid xsi:nil="true" xsi:type="xsd:string"/>
<uid xsi:nil="true"/>
</root>
Received on Thursday, 14 August 2003 08:49:28 UTC