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Authoring Schemas With XSD

Posted by timothy on from the dare-unravels-with-his-usual-aplomb dept.

Dare Obasanjo points to his own "article on O'Reilly's XML.com that specifies a set of guidlelines for authoring schemas using the W3C XML Schema Definition language commonly abbreviated as XSD. The primary theme is embracing simplicity by showing how to avoid the more complex and esoteric features of the language."

2 of 111 comments (clear)

  1. Darn DTD's by HillClimber · · Score: 5, Interesting

    As someone who's just downloading the XML Mind editor and about to write an .xsd for my data -- this is great timing! Thanks, Dare.

    I also want to gripe a bit about the complexity of XML Schema. DTD has all the restrictions I'd typically want to use (the main thing I want to do is just specify element names, contents, and attributes). The *only* problem with DTD's is that they are totally namespace-challenged!

    You can't use combine two DTD's for different namespaces into a combo document. You can't even allow arbitrary other elements in a DTD element declaration -- every element must be declared and local. Even worse, you have to pick and stick with a namespace prefix in your DTD -- defeating the whole point of globally unique namespaces.

    What I *really* want is just DTD with a smidge of namespace smarts and the ability to combine DTD's for one document. Anyone want to give it a shot?

  2. Re:Nitpick of the day... by Daniel+Dvorkin · · Score: 4, Interesting
    XSD is not a "language" any more than XML is. XSLT I suppose can be considered one.

    ...

    It's akin to those Costco salespeople who tell me that the "shweet" HP computer over there has 20GB of "RAM". It looks a bit dumb given the target audience.
    Um ... you do know what the "L" in "XML" stands for, right?

    XML is a language. So is HTML. So is SQL. Just because a language isn't Turing-complete doesn't make it not a language.

    Actually, I agree with you that XSD isn't a language -- it's a specific set of rules for using a language, XML; it would be better to call it a grammar. But saying "___ isn't a language" because ___ doesn't do everything C does is as silly as the "MySQL isn't a database (management system)" crap that floats around here every so often.

    I think the target audience is sophisticated to understand the difference between a language that's Turing-complete and one that isn't, and also to know that markup languages are still languages by any reasonable definition of the word.
    --
    The correlation between ignorance of statistics and using "correlation is not causation" as an argument is close to 1.