- From: Seaborne, Andy <andy.seaborne@hp.com>
- Date: Mon, 09 Jan 2006 14:17:45 +0000
- To: public-rdf-dawg-comments@w3.org
Forgot the [OK?] on the subject line for the scripts. Andy Seaborne, Andy wrote: > > From: Leo Sauermann <leo@gnowsis.com> > > Date: Tue, 15 Nov 2005 23:49:15 +0100 > > > > > > Hello SPARQL, > > > > I have some input regarding the definition of DESCRIBE I have two > > inputs to make, explaination below: > > * Include Concise Bounded Descriptions as a "suggested" way the Query > > Processor handles calls to Describe (not authorative, the query > > processor MAY use CBD Semantics to gather the graph for describe) > > I have added an informative reference to the CBD submission into the query > document and linked to it from the DESCRIBE section. > > > * Allow the passing of parameters to the query processor during > > describe calls > > The service description of a service would indicate what mechanisms it > provided for descriptions and any additional parameters that might be used at > a particular given service endpoint. > > The working group has decided to postpone the Service Description issue for > this working group on the grounds that designs aren't sufficiently mature yet > and so would have a large impact on the Working Group schedule. > > http://www.w3.org/2001/sw/DataAccess/issues#serviceDescription > > > If this message addresses the comments raised, please let us know. (If you > respond with [CLOSED] in the subject line it will allow the issue tracking > scripts to close this issue.) > > Thanks, > Andy > > > > > =Background info= > > > > here is the current def from > > http://www.w3.org/TR/rdf-sparql-query/#describe > > "The query pattern is used to create a result set. The | DESCRIBE| form > > takes each of the resources identified in a solution, together with any > > resources directly named by IRI, and assembles a single RDF graph by > > taking a "description" from the target knowledge base. The description > > is determined by the query processor implementation and should provide > > a useful description of the resource, where the meaning of "useful" is > > determined by the information publisher." > > > > At the moment the definition of description is taken on the server > > side, by the query processor. We know from implementations, that > > Patrick Stickler's URIQA protocol defines Concise Bounded Descriptions > > with a similar intent, but with a concrete definition > > > > http://www.w3.org/Submission/CBD/ > > > > In our gnowsis project, a Semantic Desktop, the concept of CBDs proved > > very useful for practical implementation of a larger system. Also, in > > creation of adapters to extract information from heterogenous > > datasources, CBDs are useful. > > Hence, I would suggest to include the definition of CBDs so that > > implementers MAY use this semantic, and also that clients MAY hope that > > CBDs are returned. This would also give implementors a better > > definition of what they MAY do in their implementations, allowing to > > quick-start with existing code or at least an exact decision what is > > good here (and year-long experience). > > > > A notion of CBD and URIQA is, that the user can pass parameters to the > > query processor to ask for certain properties via passed parameters. > > http://sw.nokia.com/uriqa/URIQA.html#parameters > > These parameters include parameters like > > * format > > * naming > > * inference > > * reifications > > etc. > > > > We want to change some parts of our gnowsis software to URIQA, but > > cannot use the Describe syntax as a CBD replacement at the moment, > > because we cannot pass parameters through the query engine. One use > > case is crawling: When collecting data from a server to store it into a > > RDF database (using several URIQA/CBD calls) we pass parameters to > > indicate this use. The query engine should return then minimal graphs, > > that are connected to each other. Which is not important now, but we > > need to pass a parameter "crawling=true" through the engine, to our > > query engine implementation. Hence, even If the semantics of DESCRIBE > > is not clear, we would like to use it, but to pass name/value pairs > > through the engine so that we can refine the semantics of DESCRIBE a > > little. > > > > Passing parameters would allow us, to continue the CBD and URIQA system > > here and connect it to SPARQL, and also to continue our code base. > > > > Patrick Stickler can also comment on these requirements, we have > > chatted about this during the ISWC. > > > > greetings, > > hope that this email is useful input and helps us all, Leo Sauermann > >
Received on Monday, 9 January 2006 14:19:50 UTC