- From: Chimezie Ogbuji <ogbujic@ccf.org>
- Date: Mon, 30 Mar 2009 11:17:35 -0400
- To: "Lee Feigenbaum" <lee@thefigtrees.net>
- cc: "Kjetil Kjernsmo" <Kjetil.Kjernsmo@computas.com>, "'RDF Data Access Working Group'" <public-rdf-dawg@w3.org>
I think I'm going to break this out into a separate feature request and try to better articulate the problem and suggested solutions before we run out of steam in our current feature review. > Right, but this just scopes part of the query to the dataset, which has > already been defined as above. Unless I misunderstand, the feature in > question is how does a SPARQL user specify that they want to query > against "all the graphs that the engine could possibly query". The feature I had in mind was "how does the user specify that they want to query against all the named graphs of the specified dataset" preferably as a default graph. So, it is exactly about specifying which subset of the dataset should be queried and how to carve up such subsets and (possibly) refer to them by name. > This sounds like a different feature to me: this sounds like asking for > some way to treat the named graphs in a data set as a single graph. But > I don't see any reason for that since you can just use the default graph > for that - since you already needed to have some way to define the named > graphs in your data set as containing "all graphs", you could just as > easily define the default graph as containing "all graphs". Right, but currently if this is not specified by the user (in some way, currently FROM ... is the only way) then the server can provide anything for the default graph (including an empty graph , which is what the tests in the latest test suite sanction). The motivation here is that an empty default graph is not quite as useful as a default graph that (either by default or by specific instruction from the user) is instead the merge of all the named graphs and it would be nice if there was an explicit way to specify this w/out relying on the applications behavior which could differ between systems. > Well, that's a bit different since everything inside GRAPH ?var { ... } > needs to match against a single graph from the named graph part of the > data set. Yes, I realize that now. Which means that even this would not work as a workaround for the need described above (unless the the desired behavior is to match against a single graph from the named graph). -- ---------------------- Chimezie (chee-meh) Thomas-Ogbuji (oh-bu-gee) Heart and Vascular Institute (Clinical Investigations) Cleveland Clinic (ogbujic@ccf.org) Ph.D. Student Case Western Reserve University (chimezie.thomas-ogbuji@case.edu) =================================== P Please consider the environment before printing this e-mail Cleveland Clinic is ranked one of the top hospitals in America by U.S. News & World Report (2008). Visit us online at http://www.clevelandclinic.org for a complete listing of our services, staff and locations. Confidentiality Note: This message is intended for use only by the individual or entity to which it is addressed and may contain information that is privileged, confidential, and exempt from disclosure under applicable law. If the reader of this message is not the intended recipient or the employee or agent responsible for delivering the message to the intended recipient, you are hereby notified that any dissemination, distribution or copying of this communication is strictly prohibited. If you have received this communication in error, please contact the sender immediately and destroy the material in its entirety, whether electronic or hard copy. Thank you.
Received on Monday, 30 March 2009 15:18:27 UTC