XML trade off 1 - DTD vs XML Schema

Mark Birbeck Mark.Birbeck at iedigital.net
Mon Jul 26 22:42:07 BST 1999

Rick Jelliffe wrote:
> The XML Schema supporters have never made any response to questions
> several people have raised over the last year questioning the
> practicality
> (*as a DTD replacement*) of a verbose syntax: who wants to download
> a 100K schema for a 1K instance?

I have.

I argued that increasingly, both the document and schema will be
generated dynamically from relational or object databases. In this
situation you would only need to convey the part of the schema needed to
validate the part of the 'document' passed. It therefore seems
inconceivable to me that you would need to pass a 100k schema for a 1k
document - you just pass a 'sub-set' of the schema (which is still
itself a valid schema).

An exception would be if you were allowing the recipient to edit the
document, but even then you could incrementally pass the parts of the
schema that were needed for the area being edited, so that the target
application gradually built up the full schema as and when it needed it
- a clear advantage to me of using XML for everything, including
expressing XML.

(I have devised a working prototype of this, in case people are thinking
it's too complicated.)


Mark Birbeck


xml-dev: A list for W3C XML Developers. To post, mailto:xml-dev at ic.ac.uk
Archived as: http://www.lists.ic.ac.uk/hypermail/xml-dev/ and on CD-ROM/ISBN 981-02-3594-1
To (un)subscribe, mailto:majordomo at ic.ac.uk the following message;
(un)subscribe xml-dev
To subscribe to the digests, mailto:majordomo at ic.ac.uk the following message;
subscribe xml-dev-digest
List coordinator, Henry Rzepa (mailto:rzepa at ic.ac.uk)

More information about the Xml-dev mailing list