Is there a one-to-one relationship between XML namespaces and XML Schemas?
No. As was shown in question 8.1, a schema may use elements or attributes from multiple XML namespaces. And although a given XML Schema document can only declare elements and attributes in a single XML namespace, the relationship between XML namespaces and XML Schema documents is not one-to-one. This is because multiple documents can all declare elements and attributes in the same XML namespace. When this is done, one XML Schema document can include another XML Schema document that has the same target namespace with the xs:include element. For more information, see Namespace Myth #8.
