- From: Dirk Colaert <Dirk.Colaert@quadrat.be>
- Date: Thu, 8 Apr 2004 17:06:11 +0200
- To: 'Howard Katz' <howardk@fatdog.com>, Dirk Colaert <Dirk.Colaert@quadrat.be>, Eric Prud'hommeaux <eric@w3.org>
- Cc: Rob Shearer <Rob.Shearer@networkinference.com>, public-rdf-dawg@w3.org
Use case dc-02: Query a query A server stores all queries committed. From time to time the security administrator wants to know who has tried to query on data which he/she had no access to. -----Original Message----- From: Howard Katz [mailto:howardk@fatdog.com] Sent: jeudi 8 avril 2004 16:14 To: Dirk Colaert; Eric Prud'hommeaux Cc: Rob Shearer; public-rdf-dawg@w3.org Subject: RE: Requirement: queries written as RDF > >(2) If queries are represented in XML they can be treated as data > > and you can run XQueries over a collection of XQueries. > > That's interesting. A Query expressed in RDF could be treated as RDF. It > would be easy to do queries about queries. That's an argument for > using RDF > (or a subset, or a convertible format). > > All we have to do know is find a use case justifying this > requirement... :-) It does sound wonderful, doesn't it? I too would like to know what you would want to query in a query. Examples anyone ... ? > > Or do we have a solution without a problem? > > Dirk > > -----Original Message----- > From: Howard Katz [mailto:howardk@fatdog.com] > Sent: mercredi 7 avril 2004 7:08 > To: Eric Prud'hommeaux > Cc: Rob Shearer; public-rdf-dawg@w3.org > Subject: RE: Requirement: queries written as RDF > > > I got several responses back from members of the Query wg on the XQueryX > question. I particularly liked this one. I don't know if it'll shed any > light on our own issues, but it's delightfully clear and succinct. The > author prefers to remain anonymous. > > In response to a question on why XQueryX: > > > (1) An XML-based syntax was considered easier for machines to > > generate and exchange than a human-oriented syntax that would > > require some sophisticated parsing. > > (2) If queries are represented in XML they can be treated as data > > and you can run XQueries over a collection of XQueries. > > (3) Since XML is known to be an answer to all questions, it must be > > an answer to the question "What would be a good format for expressing > > queries over XML data"? > > In response to a question on the technical difficulties that > arose once the > requirement was formulated: > > > Once the requirement for an XML query syntax was adopted, > > arguments immediately broke out over the level of detail at > which a query > > should be broken down into XML elements. The working group > finally settled > > on two separate approaches that represent extreme points on the > spectrum: > > (a) The whole query is wrapped in a <query> element, and otherwise > unchanged. > > This approach obviously does not take the XML syntax requirement very > seriously. > > (b) The query is parsed, and each and every node in the parse tree > (including individual > > operators, function calls, steps in path expressions, etc.) is > represented > by its own > > element, thus making the query incredibly verbose. This format is > obviously useless to humans. > > > At various times and places, people have attempted to define some > intermediate point > > between these two extremes. These attempts have always ended in > rancor and > controversy. > > Finally, in a follow-up clarification: > > > I believe that the editor of the XQueryX specification is currently > pursuing both approaches > > (a) minimal expansion and (b) maximal expansion. Both will be defined as > valid forms of > > XQueryX. > > Just to close on a personal note, I've always felt that XML is > the answer to > all questions. I'm now coming to feel increasingly that RDF is > even more so! > > Howard > > > > On Sun, Apr 04, 2004 at 09:23:14AM -0700, Howard Katz wrote: > > > > [snip ...] > > > > > > I certainly agree with the sentiments of the second, "human > readable" > > > > requirement. Interestingly enough, the third, "XML" requirement > > > has been the > > > > one that's caused the group the most difficulty to my > > > knowledge, and at the > > > > moment conformance with this requirement has been downgraded to > > > optional. I > > > > don't know what the major issues have been, but it might be > > > interesting to > > > > know, if only for the sake of curiosity. > > > > > > Can we go beyond the meta-lesson of "that may be hard. it's been hard > > > in XQuery" to some of the particular problems that requirement caused > > > the XQuery WG? Also, was this requirement born of some compelling use > > > cases, or a general notion that it's good practice to express anything > > > in XML? > > > > I wasn't trying to impart a particular lesson. My intention, not knowing > > what DAWG members know or don't know about it, was simply to > > provide data on > > the experience of the Query wg in the event that might prove > useful to the > > group. In response to your questions, I've asked several > members of the wg > > about their XQueryX experience. If they see fit to pass that on > > to me, I'll > > be happy to share it with the group. > > > > Howard > >
Received on Thursday, 8 April 2004 10:59:33 UTC