xml-dev - RE: XML Schemas: Best Practices

["Arnold, Curt" <Curt.Arnold@hyprotech.com>]

In my opinion, you have to consider who "owns" the namespaces
and if the namespaces are useful in other contexts.  For example, consider the use of XHTML or SVG in a health care schema.  

XHTML and SVG would not be owned by the same organization as the health care schema, they are not updated simultaneously with the health care schema, and they are useful apart from the health care
schema.  In this case, if you tried to incorporate XHTML or SVG tag names into the health care namespace (creating a health:table element for example), then you would lose interoperability with any
existing applications that would process <xhtml:table> but would not recognize <health:table>.  I definitely think that creating aliases is a bad idea.

If you don't have control over the source for a schema (as would be the case for the W3C's XHTML or SVG schema), you should import the namespace.

If you have a case where you have control over the schemas, then you have to consider if a potential namespace would be useful in other contexts.  For example, if I'm doing XML schemas for
automobiles, I might consider making a distinct namespace for tires if:

a) I might reuse the tires namespace in another context, say an XML schema for Trucks
b) I might had over control of the tires namespace to a different group or organization than the organization that owns the automotive namespace.