2009/9/2 Simon Cox <simon.cox@j...>:
> In some situations it is good to include dates or version numbers in
> namespace names.
> For example, if your maintenance/governance arrangement expects new
> versions, and particularly if the new versions are not compatible with older
> versions.
> Geography Markup Language from OGC made the mistake of keeping the same XML
> namespace for several incompatible versions of GML, and this has caused
> confusion. (The policy has since been fixed).
>
> Of course, you can choose to give your new version a completely new name and
> namespace, but sometimes you want to claim continuity, or at least a common
> scope, with an earlier product, but not confuse processors by having
> incompatible declarations in the same target namesapce.

Interesting, I would still be tempted to keep the same namespace and
use a version attribute to distinguish the versions.  If those
versions are "compatible" or not doesn't really matter at the data
level, all you need to be able to do is differentiate your elements
from others with the same local name, and differentiate the versions.

In "GML", where do you think the confusion came from?  Unless they
also changed the prefix between versions, looking at snippets of
markup you would still be none the wiser.



-- 
Andrew Welch
http://andrewjwelch.com
Kernow: http://kernowforsaxon.sf.net/