RE: Impact of XML on Data Modeling

 > If these observations are correct, my next question would be: Is the W3C
XML Schema the best choice on the market today for data modeling in the XML
world?  (why or why not) 
 
I think there are two difficulties in using XML Schema for modelling.
 
One is syntax - a model, by definition, captures the essential qualities of
the real thing and leaves out unnecessary detail. XSDL isn't really a
language that allows you to forget about the detail, or to refine it
incrementally. It's a bit like trying to use Java for modelling.
 
The other is the focus on describing the structure of a particular document
type or message type. This is OK in situations where the document is the
data. But in situations where the document is a message, a transient data
flow between components of the application, it works less well, because it's
difficult to capture the areas of commonality between all those messages -
there's some underlying data model and it's only distantly related to the
structure of all the messages that are flying around. 
 
Michael Kay
http://www.saxonica.com/