RE: [xml-dev] element versioning

> 
> Is it possible to track versions of elements in schemas?
> 
> I've tried to add two attributes, ID (xsd:ID) and version
> (xsd:positiveInteger), but then the instance won't validate 
> when I add two
> elements with the same ID.
> 

xsd:ID values have to be unique within a document. If you want a more
elaborate constraint (combination of ID and version being unique) you can do
it with an xs:unique constraint in the schema.

Michael Kay