The subset of XPath allowed in specifying uniqueness constraints doesn't
allow predicates, and doesn't allow use of the sibling axes, so I don't
think this is possible.

Michael Kay
http://www.saxonica.com/
 

> -----Original Message-----
> From: xmlschema-dev-request@w... 
> [mailto:xmlschema-dev-request@w...] On Behalf Of AYDOS Carlos C
> Sent: 20 September 2005 09:05
> To: xmlschema-dev@w...
> Subject: complex uniqueness
> 
> 
> Hi,
> 
> Does anyone knows if its possible to create a xs:key to 
> guarantee that the below instance document could have a 
> uniqueness constraint among names A,B,C,D of only the 2nd,3rd 
> and 4th pointSets (they are linked via the attribute 'extends')
> 
> Carlos
> 
> <root>
> 	<pointSet type="ordinary">
> 		<point name="A"/>
> 		<point name="B"/>
> 	</pointSet>
> 	<pointSet type="basic">
> 		<point name="A"/>
> 		<point name="B"/>
> 	</pointSet>
> 	<pointSet type="complex" extends="basic">
> 		<point name="C"/>
> 	</pointSet>
> 	<pointSet type="verycomplex" extends="complex">
> 		<point name="D"/>
> 	</pointSet>
> </root>
> 
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From K.Buchcik@4... Wed Sep 21 10:05:07 2005
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