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

RE: (data) medium is the message

  • To: "'xml-dev'" <xml-dev@l...>
  • Subject: RE: (data) medium is the message
  • From: Jeff Lowery <Jeff.Lowery@c...>
  • Date: Thu, 1 May 2003 11:33:00 -0700

avoiding data replication in xml
> I'm interested in your reasons why not. I can think of some. 

I'm thinking of reports, which are classically unnormalized.  XML data for a
report may be divided into pages.  For a two-page bill, the customer name
and account ID may appear twice (once on each page).  Yes, you could use
ID/IDREF or key/keyRef to avoid the duplication in the XML source, but that
seems like overkill in most cases.

Also, reports often contain parent-child relations that are implied by
colocation of data (like the name/address example I gave at the beginning of
the thread).  While it's perhaps not good XML design to flatten those
hierarchies by a transform, I would expect it to happen nonetheless.

>  OTOH if documents are unjoined normalized 
> selections and
> projections from the original relational data, updates from 
> the documents
> would be simpler. Or is this just hopelessly naive?

If you have access to the original data, yes.  If you only have secondary
access through projected data documents, then you're stuck with having to
augment the information you recieve in order to automate it.  It may be an
uncommon situation for internal applications that you can't get access to
the prime data source, although I've worked at companies large enough where
that was the case (either for security reasons, or for bureaucratic ones).

Another example is where you're required to consume standard XML documents
used for cross-business data interchange.  While you might assume the
promulgating standards body behind the document model would have a clue
about avoiding data replication and to use hierarchies or references to
denote relations, I think practice will show that you might assume too much.


I'll now defer to the  more promiscuous among the list (the XML
consultants), who might wish to take a turn at the podium and describe what
driving in the fast (and loose) lane is like.


PURCHASE STYLUS STUDIO ONLINE TODAY!

Purchasing Stylus Studio from our online shop is Easy, Secure and Value Priced!

Buy Stylus Studio Now

Download The World's Best XML IDE!

Accelerate XML development with our award-winning XML IDE - Download a free trial today!

Don't miss another message! Subscribe to this list today.
Email
First Name
Last Name
Company
Subscribe in XML format
RSS 2.0
Atom 0.3
 

Stylus Studio has published XML-DEV in RSS and ATOM formats, enabling users to easily subcribe to the list from their preferred news reader application.


Stylus Studio Sponsored Links are added links designed to provide related and additional information to the visitors of this website. they were not included by the author in the initial post. To view the content without the Sponsor Links please click here.

Site Map | Privacy Policy | Terms of Use | Trademarks
Free Stylus Studio XML Training:
W3C Member
Stylus Studio® and DataDirect XQuery ™are products from DataDirect Technologies, is a registered trademark of Progress Software Corporation, in the U.S. and other countries. © 2004-2013 All Rights Reserved.