- From: Lee Feigenbaum <feigenbl@us.ibm.com>
- Date: Mon, 7 May 2007 11:10:37 -0600
- To: ogbujic@ccf.org
- Cc: public-rdf-dawg-comments@w3.org
Hi Chimezie, The working group considered this issue and decided not to make any change at this time. For the record, you are now a member of the working group and have indicated that you are satisfied with us closing this issue, so I am marking this thread closed. thanks, Lee Chimezie Ogbuji wrote on 04/04/2007 03:05:38 PM: > > This was discussed in #swig > (http://chatlogs.planetrdf.com/swig/2007-04-03.html#T20-38-01) > > SPARQL currently does not provide an unambiguous way to specify a > dataset which corresponds to all the known named graphs. The only way > this can be done is to leave out FROM <..> and FROM NAMED <..> > directives in the prolog (and from the protocol, for SPARQL services). > The corresponding dataset in this case depends on the host application - > not very consistent. The only other alternative is to explicitly > enumerate the known universe in the prolog: > > FROM NAMED G1 > FROM NAMED G2 > ... > FROM NAMED GN > > This is not practical for a dynamic dataset. > > There is plenty of value in querying against the known universe > consistently especially for applications which make use of a dataset as > a named graph partition that can grow indefinitely. Consider XPath > 2.0 / XQuery 1.0 which supports querying a collection of XML documents > without having to explicitly enumerate all the XML documents in the > collection. > > This is a very useful 'database-wide' query pattern which is well > supported in document-management languages but not supported in SPARQL > without assuming the implementation will consistently supply the dataset > corresponding to all the known named graphs in persistence in the > absence of any dataset directives in the prolog or at the protocol > level. > > Other than OWA or CWA issues, I don't see why an explicit syntax for > binding to such a dataset is not supported by SPARQL to provide a > consistent way for applications to dispatch these kinds of queries. > Such a syntax was suggested in the above conversation: > > FROM NAMED * > > [1] http://www.w3.org/TR/xquery-semantics/#sec_fn_doc_collection > > -- > Chimezie Ogbuji > Lead Systems Analyst > Thoracic and Cardiovascular Surgery > Cleveland Clinic Foundation > 9500 Euclid Avenue/ W26 > Cleveland, Ohio 44195 > Office: (216)444-8593 > ogbujic@ccf.org > > > > > > > Cleveland Clinic is ranked one of the top 3 hospitals in > America by U.S.News & World Report. 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, 7 May 2007 17:10:43 UTC