Re: A good argument for XML

Tom Bradford wrote:
> Gene Wirchenko wrote:
> > The problem has been solved before. XML is solving old problems.
>
> What was the solution for mixed content then?

An insight I have had lately is that the xml people are at heart document management people. By and large they don't have any history with data management, and don't understand what it is for or what it needs to do.

Then they try to evaluate things like sql *as a document management system* and note that it doesn't work very well. Where is the full text search? How come I can't find related documents? What do I do about mixed content? All questions that make sense in the document management field and really miss the point of data management entirely.

The nasty bit seems to come in to play because the xml people have somehow gotten it into their heads that data management and document management are really the same problem. They think that their techniques have some relevance to the problems of structure, integrity, and manipulation, when in fact they don't, at all, because the two fields are almst completely disjoint.

> There are many people
> that would argue that SGML was no solution at all because the document
> structure was not explicit enough on its own to imply any form of
> validity or well-formedness, thus a DTD was required with every parse.
> XML, in that sense was a step in the right direction, especially
> considering that the infrastructure of the web was already built on top
> of SGML, which for the most part, looks like XML.

Note how much this paragragh has to do with document management and how it has nothing to do with data management.

> > And just because you can come up with an alternative does not
> > make that alternative the end-all and be-all. That is the way the XML
> > pushers push though.
>
> I've seen the same arguments from people like Fabian Pascal... that
> somehow the relational model, which was an alternative to previous
> models, is the end all be all. Fact is that XML zealots admit that XML
> is not the end all be all for data representation, and they often design
> systems that are hybrids between relational storage and XML
> representation/storage, leaving each respective system to doing what
> they do best. You don't often find that type of opional flexibility in
> relational zealots.

Speaking as a relational zealot, let me just say that there are lots of document management issues to which I don't think the field of data management has much to offer. Full text indexing, for example.

I still don't see that xml has any least interesting thing to contribute to the field of data management, though. I suppose it might, but you'd think if it did, someone could point out something, something about *data management* and not *document management* that is better/easier/cleaner/simpler with xml that with the RM. Or even than just with sql.

Of course, this does nothing to explain away people like Jan Hidders, who clearly have a deep understanding of the RM and yet remain fascinated with xml. I have to say I find that a puzzle.

Marshall Received on Wed Jul 13 2005 - 05:04:34 CEST