• To: xml-dev@l...
• Subject: Re: XQuery types was Re: Yet another plea for XUpdate...
• From: Jonathan Robie <jonathan.robie@d...>
• Date: Mon, 06 May 2002 08:18:53 -0700
• In-reply-to: <20020504171233.23522.qmail@w...>
• References: <008201c1f3dc$3378e440$0301a8c0@n...>

At 10:12 AM 5/4/2002 -0700, Dare Obasanjo wrote:
>The bottom line is that any XML database product that
>supports XQuery and W3C XML schema plus an update
>capability will have to support post-update validation
>because the XQuery and W3C XML Schema "type" systems
>leave the door open for too many things to be dynamic.
>
>
>By the way here are some quotes from the Formal
>Semantics document which point out what I mean by
>validation vs. type system

[ !!! SNIP !!!]

>Especially with regards to restriction facets, there
>simply is no way for this to be implemented without
>something akin to post-update validation. Identity
>constraints as well. In fact, when I think about even
>making sure that the results of an update do not
>result in an invalid content model for an element in
>the document is pretty much another validation issue
>not a type one.

Static analysis is not an all-or-nothing thing. Relational databases do not 
use static analysis for constraints on values, but static analysis is 
important for relational databases.

Restriction facets are generally constraints on values.

Jonathan

• References:
  • XQuery types was Re: Yet another plea for XUpdate...
    • From: "Jonathan Borden" <jborden@a...>
  • Re: XQuery types was Re: Yet another plea for XUpdate...
    • From: Dare Obasanjo <kpako@y...>

• Prev by Date: Re: Call for example of server enabled for XML multiple representations
• Next by Date: Re: XQuery types was Re: Yet another plea for XUpdate...
• Previous by thread: Re: XQuery types was Re: Yet another plea for XUpdate...
• Next by thread: New approach
• Index(es):
  • Date
  • Thread