[PDF] Top 20 Flexible query processing for SPARQL

... applying flexible querying to the Semantic Web, mainly employing similarity measures to retrieve additional answers of possible ...of SPARQL is developed called iS- PARQL which uses three different matching ... See full document

... of set semantics, column ordering, duplicates and handling of nulls. SQL has been formally reconstructed using bags (a collection of values that allow duplicates) rather than sets (a collection of values that allows no ... See full document

... RDF query languages to query such data, and SPARQL is one of ...the SPARQL queries are very slow for RDF data with millions of ...a Query Performance Appraisal using SPARQL & ... See full document

... containing all query keywords. Current techniques for supporting such queries on general graphs suffer from several drawbacks, e.g., poor worst-case performance, not taking full advantage of indexes, and high ... See full document

... to query large data dumps, as well as continuous streaming data ...to query only for Subject-Segmented or sorted data streaming [14], ...The Query Engine executes the parser of the Filter clause and ... See full document

... The Resource Description Framework (RDF) is a language designed to support the Semantic Web. RDF is a framework for supporting resource description, or metadata (data about data), for the Web. RDF provides common ... See full document

... ontology-based SPARQL query answering via query rewriting over Linked Data sources, where the ontology is given by conjunctive mappings between the source schemas in a peer-to-peer fashion, and by ... See full document

... Each query is executed 20 times (see Figure 9) and the average query processing time is used as the ...the processing time up to 79% (average time of processing queries in the ... See full document

... a query evaluation algorithm based on query rewriting that returns results incre- mentally according to their “distance” from the original ...user’s query, the data and the user’s knowledge of the ... See full document

... The Semantic Web is the extension of the World Wide Web that enables people to share content beyond the boundaries of applications and websites. It has been described in rather different ways: as a utopic vision, as a ... See full document

... The SPARQL query language is the standard for retrieving linked open data from triple ...stores. SPARQL is powerful, flexible, and allows the use of RDF, with all of its advantages over tradi- ... See full document

... improving mechanized access and processing. For example, in Linked Data, Uniform Resource Identifiers (URIs) are used to refer to all data entities; moreover, by convention and best practice, these URIs should (in ... See full document

... Clearly, the intermediate table could be projected within the final results expression (see section 5.4). Keeping it separate at this stage of the processing has advantages when dealing with more complex ... See full document

... increasing computing performance for par-allel problems with use of Graphics Processing Units. It also provides low and high level APIs (application programming interfaces) with debuggers, shared memory ac-cess, ... See full document

... graph query- ing against historical graphs, identifying subgraphs enduring graph mutations over time [35], which can be viewed as a variation whereby graph snapshots in time can be viewed as different ...the ... See full document

... Figure 2 presents the service process triggered after a malfunction of a unit (i.e., reactive scenario) [20]. In this case, a service ticket requesting assistance is cre- ated either manually or automatically by a ... See full document

... formulate SPARQL queries to extract the data they are interested in viewing, but then require guidance as to which visualisation method can be used, and we use OWL schema information such as that presented in ... See full document

... such, SPARQL queries that are successful one day, may not be successful the ...pure SPARQL interface would be; updating the OpenLifeData2SADI behavior is simply a matter of changing the configuration file, ... See full document

... The Web contains vast amounts of data from many heterogeneous sources, and the harvesting of in- formation from these sources can be extremely valuable for several domains and applications such as, for instance, business ... See full document

... GRDDL - Gleaning Resource Descriptions from Dialects of Languages (a means to extract RDF from XML or XHTML documents). SPARQL – a query language for RDF data.[r] ... See full document