Re: Beyond schema

[Jeff Greif <jgreif@alumni.princeton.edu>]

In general, checking an XML document against business rules is likely to
require application code as well as relying on some document description
format like XML schemas.  If the constraints fall within certain classes,
there are alternatives to XML Schema, such as Schematron or RELAX-NG.  Most
likely, application logic will be needed.  If business rules change
frequently, it is best to implement them not as individual chunks of hard
code, but as declarative forms in a special rule language that's easy to
comprehend and change, processed by some kind of rule engine.  If you're
doing it in java, you might investigate JESS, which is an expert system
shell.  If you want more information, please write to me privately.

Jeff

----- Original Message -----
From: <Philippe.Peeters@smals-mvm.be>
To: <xml-dev@lists.xml.org>
Sent: Wednesday, August 01, 2001 8:16 AM
Subject: Beyond schema


| Hi there,
|
| I am quite new to XML developpement (and to this list) but I have a
| question concerning the validation of XML messages (or data structure)
| beyond what is allowed by a XML schema.
...
| When we receive the data (the xml message) we need to check the structure
| (is the message valid according to the schema) but we also need to
| implement  particular business rules. For exemple, a field A in the
message
| is required if, and only if, the value of some other field B in the
message
| is defined in a extrnal list of values.