Liam Quin wrote:
> XSLT 2 is built on a logical data model, although
> not one described in terms of relational algebra.
Thanks Liam.
I took a look at the XPath Data Model [1]. It's all prose. There are
no UML-type diagrams.
In fact, I can't find any documents on XSLT, XML Schema, XHTML, or
Schematron that contain UML- or ER-type diagrams. The documents are
all prose. The prose defines and describes concepts at an abstract
(infoset) level.
As far as I can tell, the "logical data model" used to create an XML
vocabulary is different than the "logical data model" used to create a
database- or object-system.
Here are the differences that I see:
Creating a database or object system involves:
. create UML- or ER-type diagrams, and then
. create the database or object system directly
from those diagrams.
Conversely, creating an XML vocabulary involves:
. define and describe in prose the concepts
at an abstract (infoset) level, and then
. create a specification from that prose, and then
. create an XML Schema or DTD or Relax NG schema.
Do you agree?
/Roger
[1] http://www.w3.org/TR/xpath-datamodel/#dt-instance
