- From: <Ulrich.Post@softwareag.com>
- Date: Tue, 7 Dec 2004 18:59:48 +0100
- To: <www-xml-schema-comments@w3.org>
- Message-ID: <0AE50E462665EB4898CACAC8DA16982203F08C0B@DAEMSG03.eur.ad.sag>
Hello
I'm wondering whether the following is a bug in the XML Schema
Recommendation:
At http://www.w3.org/TR/xmlschema-1/#rcase-NameAndTypeOK
<http://www.w3.org/TR/xmlschema-1/> it is stated that
"3.2.3 R's declaration's {identity-constraint definitions}
<http://www.w3.org/TR/xmlschema-1/> is a subset of B's declaration's
{identity-constraint definitions}
<http://www.w3.org/TR/xmlschema-1/> , if any."
To my opinion this would mean, that there are fewer constraints on R
than on B
- which is probably not intended.
Look at the following two element declarations:
(1)
<xs:element name="e">
<xsd:complexType>
<xsd:sequence>
<xsd:element name="uid" maxOccurs="unbounded"/>
</xsd:sequence>
</xsd:complexType>
</xs:element>
(2)
<xs:element name="e">
<xsd:complexType>
<xsd:sequence>
<xsd:element name="uid" maxOccurs="unbounded"/>
</xsd:sequence>
</xsd:complexType>
<xsd:unique name="uid">
<xsd:selector xpath="uid"/>
<xsd:field xpath="."/>
</xsd:unique>
</xs:element>
Obviously, (1)'s identity constraints are a subset of (2)'s.
When looking at these I end up with the conclusion that (2) is a valid
restriction of (1) rather than vice versa.
Would you agree on this?
Best regards
Uli Post
Received on Tuesday, 7 December 2004 18:00:31 UTC