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

RE: XML and Queries (not XQL)

  • From: Michael Rys <mrys@m...>
  • To: "'Jonathan.Robie@S...'" <Jonathan.Robie@S...>,sellberg@k..., xml-dev@l...
  • Date: Thu, 22 Feb 2001 10:27:29 -0800

annotated schemata
Title: RE: XML and Queries (not XQL)
Well, then I misunderstood your interpretation of the original email, because I interpreted his first question differently.
 
Best regards
Michael
-----Original Message-----
From: Jonathan.Robie@S... [mailto:Jonathan.Robie@S...]
Sent: Thursday, February 22, 2001 10:20 AM
To: Michael Rys; Jonathan.Robie@S...; sellberg@k...; xml-dev@l...
Subject: RE: XML and Queries (not XQL)

Hi Michael,

I think we actually agree. I interpreted the original question as (1) can you represent an SQL query well in XML syntax, and (2) can you represent a relational database with an XML view and query it with an XML query language. I said "I doubt it" to (1), and "yes" to (2).

Jonathan

-----Original Message-----
From: Michael Rys
To: 'Jonathan.Robie@S...'; sellberg@k...; xml-dev@l...
Sent: 2/22/01 12:57 PM
Subject: RE: XML and Queries (not XQL)

I would like to disagree with Jonathan here. There are approaches to use
(annotated) schemata (not necessarily DTDs) to define XML views over
relational datat that then can be queried using an XML query language.
XPath against annotated schemata in SQLServer 2000 is one example.
 
Also, please note that the use case R1 is representing only one
potential serialization/view of relational data (and not my preferred
one, I may add).
 
However, using the schema language alone to perform queries becomes
pretty unwieldy. One of the best ways that utilize DataGuides
(instance-inferred schema) for a visual query interface see Lore (the
queries were translated into Lorel, Lore's query language).
 
Best regards
Michael
 

-----Original Message-----
From: Jonathan.Robie@S...
[mailto:Jonathan.Robie@S...]
Sent: Thursday, February 22, 2001 9:32 AM
To: sellberg@k...; xml-dev@l...
Subject: RE: XML and Queries (not XQL)



Selberg wrote:

> Are there examples of using XML as a substitute for
> an SQL query? I mean examples of using a DTD to define
> a valid search given as XML as the search criteria in
> a database?

I have seen several approaches to this. None of them seemed all that
useful.

> Is it a good idea to make an abstraction of a
> valid database entity in a DTD and make an abstraction of
> a valid search criteria in a DTD? I have searched for such
> examples and I couldn't find any. Maybe the lack of such
> examples is telling me that it is not a way to go. XQL
> is not what we need.

The XML Query Working Group's use cases include "Use Case R" [1], which
performs queries on an XML view of a relational database. The use case
assumes these views are created automatically.

Jonathan

[1] Use Case R ( http://www.w3.org/TR/xmlquery-use-cases#rdb
<http://www.w3.org/TR/xmlquery-use-cases#rdb> )


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.