- From: Chimezie Ogbuji <ogbujic@bio.ri.ccf.org>
- Date: Fri, 23 Jun 2006 09:52:29 -0400 (EDT)
- To: public-sparql-dev@w3.org
> Richard Cyganiak wrote: >> >> Olaf, >> >> On 22 Jun 2006, at 11:15, Olaf Hartig wrote: >>> In a recent paper about "Semantics and Complexity in >>> SPARQL" (http://www.dcc.uchile.cl/~cgutierr/ftp/sparql-ext.pdf) Perez >>> et.al. >>> mention two approaches to compute solutions for graph patterns - one >>> using a >>> procedural semantics and another using a compositional semantics. As a >>> real >>> implementation for the first they name Jena's ARQ. I'm interested in an >>> implementation following the second approach. Does someone, familiar >>> with the >>> paper, know of any? RDFLib's recently added SPARQL processor uses a hybrid approach. It has two parts, a 'core' processor (Ivan Herman's sparql-p [1]) which is explicitely procedural and a pre-processing step which applies some of the equivalencies mentioned in the above paper to 'normalize' certain graph patterns. The pre-processing happens first before the normalized pattern(s) are passed on to the 'core' processor. See RDFLib dev mailing list post on this addition [2] [1] http://www.ivan-herman.net/WebLog/WorkRelated/SemanticWeb/RDFLib/sparql-rdflib-3.html [2] http://rdflib.net/pipermail/dev/2006-June/000037.html 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
Received on Friday, 23 June 2006 13:52:37 UTC