@prefix foaf: . @prefix ns1: . @prefix ns2: . ns1:olaf-hartig foaf:made ns2:iswc-2017-iswc-2017-posters-and-demos-599 . ns1:axel-cyrille-ngonga-ngomo foaf:made ns2:iswc-2017-iswc-2017-posters-and-demos-599 . ns1:muhammad-saleem foaf:made ns2:iswc-2017-iswc-2017-posters-and-demos-599 . ns1:tommaso-soru foaf:made ns2:iswc-2017-iswc-2017-posters-and-demos-599 . @prefix ns3: . @prefix ns4: . ns4:proceedings ns3:hasPart ns2:iswc-2017-iswc-2017-posters-and-demos-599 . @prefix rdf: . @prefix ns6: . ns2:iswc-2017-iswc-2017-posters-and-demos-599 rdf:type ns6:InformationObject , ns6:Object . @prefix rdfs: . ns2:iswc-2017-iswc-2017-posters-and-demos-599 rdf:type rdfs:Resource , ns3:InProceedings , ns6:SocialObject . @prefix ns8: . ns2:iswc-2017-iswc-2017-posters-and-demos-599 rdf:type ns8:ProceedingsPaper . @prefix owl: . ns2:iswc-2017-iswc-2017-posters-and-demos-599 rdf:type owl:Thing ; rdfs:label "Federated SPARQL Query Processing Via CostFed" . @prefix ns10: . ns2:iswc-2017-iswc-2017-posters-and-demos-599 owl:sameAs ns10:iswc-2017-iswc-2017-posters-and-demos-599 . @prefix ns11: . ns2:iswc-2017-iswc-2017-posters-and-demos-599 ns11:abstract "Efficient source selection and optimized query plan generation belong to the most important optimization steps in federated query processing. This paper presents a demo of CostFed, an index-assisted federation engine for federated SPARQL query processing. CostFed's source selection and query planning is based on the index generated from the SPARQL endpoints. The key innovation behind CostFed is that it considers the skew distribution of the resources to perform efficient source selection and cost-based query planning. Our experiments on the FedBench benchmark that CostFed on average is 3 to 121 times faster than the state of the art." . @prefix dc: . ns2:iswc-2017-iswc-2017-posters-and-demos-599 dc:creator ns1:tommaso-soru , ns1:alexander-potocki , ns1:axel-cyrille-ngonga-ngomo , ns1:muhammad-saleem , ns1:olaf-hartig , ns1:martin-voigt . @prefix xsd: . ns2:iswc-2017-iswc-2017-posters-and-demos-599 dc:subject "RDF"^^xsd:string , "SPARQL"^^xsd:string , "Federated query"^^xsd:string ; dc:title "Federated SPARQL Query Processing Via CostFed" . @prefix ns14: . @prefix ns15: . ns2:iswc-2017-iswc-2017-posters-and-demos-599 ns14:authorList ns15:iswc-2017-iswc-2017-posters-and-demos-599 ; foaf:maker ns1:martin-voigt , ns1:axel-cyrille-ngonga-ngomo , ns1:muhammad-saleem , ns1:alexander-potocki , ns1:tommaso-soru , ns1:olaf-hartig ; ns3:abstract "Efficient source selection and optimized query plan generation belong to the most important optimization steps in federated query processing. This paper presents a demo of CostFed, an index-assisted federation engine for federated SPARQL query processing. CostFed's source selection and query planning is based on the index generated from the SPARQL endpoints. The key innovation behind CostFed is that it considers the skew distribution of the resources to perform efficient source selection and cost-based query planning. Our experiments on the FedBench benchmark that CostFed on average is 3 to 121 times faster than the state of the art." ; ns3:hasAuthorList ns15:iswc-2017-iswc-2017-posters-and-demos-599 ; ns3:isPartOf ns4:proceedings ; ns3:keyword "Federated query"^^xsd:string , "SPARQL"^^xsd:string , "RDF"^^xsd:string ; ns3:title "Federated SPARQL Query Processing Via CostFed" . ns1:alexander-potocki foaf:made ns2:iswc-2017-iswc-2017-posters-and-demos-599 . ns1:martin-voigt foaf:made ns2:iswc-2017-iswc-2017-posters-and-demos-599 .