[XML-DEV Mailing List Archive Home] [By Thread] [By Date] [Recent Entries] [Reply To This Message]

Re: Are people really using Identity constraints specified in

• To: "Thomas B. Passin" <tpassin@c...>
• Subject: Re: Are people really using Identity constraints specified in XML schema?
• From: w3c@d...
• Date: Thu, 19 Aug 2004 22:06:27 -0400
• Cc: xml-dev@l...
• In-reply-to: <412514A9.7030307@c...>
• References: <200408191615.i7JGFTA05579@s...> <412514A9.7030307@c...>
• User-agent: Internet Messaging Program (IMP) 3.2.2 / FreeBSD-4.8

Thomas,

When I read this I feel good about how we have engineered CAM.

These real world examples show that we have it right - since it
can handle all of this in its stride.  3 different ways of 
looking at one value?  No problems.  And context driven - yes!

Sure people can bitch about this not being 'simple' - but the
kind of use cases you have shown only proves you need strong
adaptability and flexibility to solve these real world needs.

Fortunately - unlike Tim's thoughts on XQuery - I feel very
confident that CAM has managed to address the needs.

Thanks, DW.
============================================================
Quoting "Thomas B. Passin" <tpassin@c...>:

> Roger L. Costello wrote:
> 
> > - The value of the <minimum-age> must be an integer.  This is a 
> > constraint on the data.  It will not change over time.
> 
> Ha! What happens when the government decides that some relevant age is
> 67.5 years instead of 67?
> 
> > Therefore, an XML Schema should simply constrain <minimum-age> to be 
> > an integer.  Higher level applications should implement the business 
> > rule that <minimum-age> be further constrained to 16.
> > 
> > How would you characterize the distinction between "business rules" 
> > and "constraints on data"?
> 
> A tricky, tricky issue - what is or is not a "business rule".  I suspect
> that in practice most constraints that are not business rules are in
> place for supposed programming reasons, or by force of habit.
> 
> In one project I work on, we have a data type that is a union of 1) an
> enumeration of strings, 2) a string that follows a certain regex 
> pattern, and 3) an integer constrained to a certain range.  No, don't 
> bother to ask - it's one of those multi-agency reconciliations.
> 
> -- 
> Thomas B. Passin
> Explorer's Guide to the Semantic Web (Manning Books)
> http://www.manning.com/catalog/view.php?book=passin
> 
> -----------------------------------------------------------------
> The xml-dev list is sponsored by XML.org <http://www.xml.org>, an
> initiative of OASIS <http://www.oasis-open.org>
> 
> The list archives are at http://lists.xml.org/archives/xml-dev/
> 
> To subscribe or unsubscribe from this list use the subscription
> manager: <http://www.oasis-open.org/mlmanage/index.php>
> 
> 

• References:
  • RE: Are people really using Identity constraints specified in XML schema?
    • From: "Roger L. Costello" <costello@m...>
  • Re: Are people really using Identity constraints specifiedin XML schema?
    • From: "Thomas B. Passin" <tpassin@c...>

• Prev by Date: Re: Slides from "Web Services Security Issues"
• Next by Date: RE: Are people really using Identity constraints specif ied in XML schema?
• Previous by thread: Re: Are people really using Identity constraints specifiedin XML schema?
• Next by thread: Re: Are people really using Identity constraints specifiedin XML schema?
• Index(es):
  • Date
  • Thread