RE: [xml-dev] Caught napping!

["Bill de hOra" <bdehora@interx.com>]

> Mike Champion:
> 
> XML does not claim to be a general theory of data; 
> it does not compete in that respect with the 
> relational model, so it's not 
> "ill-defined/under-specified". 

Right. I'm sure the absence of a data model won't stop people trying
however.


> BUT XML is suitable for a particular class (a large one!) of 
> problems where
> relationships are defined hierarchically -- "IS-A", 
> "PART-OF", etc. and the
> "document", not the elements/attributes in it, is the basic 
> unit of work.

I thought, that not having clear meaning for relations like partOf, was
precisely the limitation of XML. DTDs, and XMLSchema, for this class of
problems, ie that these relations are not in fact defined semantically. 


> In this class of problems, integrity constraints and update 
> semantics are
> not salient issues. In that class of problems, XML databases 
> can be quite
> appropriate solutions because they do not force one to consider the
> logical-physical mapping:  

Neither does the relational model. Finding such an implementation based
on it is another matter ;)

regards,
Bill de hÓra