Perspective on XML: Be humble, not imperial "The revolt against imperial modeling of code has already taken shape in the form of languages and agile methods. Agile programming emphasizes highly iterative development in close collaboration with the eventual users of the product. Even more important, it stresses the inevitability of change and evolution. In effect, agile developers pride themselves on being able to rapidly accommodate change."
"The same revolution is in the offing for data modeling. There have been some developments in agile databases which, literally, adapt the ideas of agile programming to the design of (usually relational) databases, but there is also progress occurring in semi-structured databases and, in particular, XML."
Is XML Zen in opposition to "strong" data modeling? "One thing I seem to share with so many of my colleagues in the XML world is a wary attitude towards traditional data modeling practices. It's an attitude that has also informed my thinking in related articles pondering data supermodels, coupling of distributed systems, OO encapsulation, and the like.
Some of us see XML as a bit of a refuge from established schools of data modeling. OO and Unified Process in my case, E-R and other relational based modeling in others'. Some just came from document-centric backgrounds where such extremely rationalized data modeling was not the mainstay. In my case, interest in XML was part of a general interest in data modeling as a vehicle for human expression rather than for robotic simulation of the real world."
As I've said before, XML is not relational enough and RDF is relational or rather "RDF provides a relational data model of the Web".