ORA-DM-INCONSISTENT-DMS

*Data Model, Section 3.3* /"The data model supports incompletely 
validated documents, but inconsistent data models are forbidden."/
The two occurrences of "data model" in this sentence presumably refer to 
different notions. The first is "THE data model", ie, the subject of 
this specification. I don't know what the second "data model" is 
referring to, since presumably this specification is taking pains to 
insure that it is not inconsistent. My best guess is that the second 
"data model" is referring to an instance of the data model.
Assuming we reword the sentence as "...inconsistent instances of the 
data model are forbidden", we are left with the question of defining 
what makes an instance "inconsistent". Perhaps what is meant is that the 
remainder of the specification contains constraints on the data model, 
and instances are forbidden to violate those constraints. Also, since 
the constraints of XML 1.0 do not necessarily apply (see the note at the 
end of section 4.2.4 "Data model to infoset mapping", which says that 
the document information item is not necessarily valid), we can not just 
assume that the collection of constraints that do apply are obvious; 
there needs to be explicit statement of what the constraints are.

Note: see also

http://lists.w3.org/Archives/Public/public-qt-comments/2003May/0104.html