Scalable Numerical SPARQL Queries over Relational Databases
2014 (English)Conference paper (Refereed)
We present an approach for scalable processing of SPARQL queries to RDF views of numerical data stored in relational databases (RDBs). Such queries include numerical expressions, inequalities, comparisons, etc. inside FILTERs. We call such FILTERs numerical expressions and the queries - numerical SPARQL queries. For scalable execution of numerical SPARQL queries over RDBs, numerical operators should be pushed into SQL rather than executing the filters as post-processing outside the RDB; otherwise the query execution is slowed down, since a lot of data is transported from the RDB server and furthermore indexes on the server are not utilized. The NUMTranslator algorithm converts numerical expressions in numerical SPARQL queries into corresponding SQL expressions. We show that NUMTranslator improves substantially the scalability of SPARQL queries based on a benchmark that analyses numerical logs stored in an RDB. We compared the performance of our approach with the performance of other systems processing SPARQL queries to RDF views of RDBs and show that NUMTranslator improves substantially the scalability of numerical queries compared to the other systems’ approaches.
Place, publisher, year, edition, pages
2014. 257-262 p.
Computer and Information Science
IdentifiersURN: urn:nbn:se:uu:diva-275027OAI: oai:DiVA.org:uu-275027DiVA: diva2:898478
4th International workshop on linked web data management (LWDM 2014) in conjunction with the EDBT/ICDT 2014 Joint Conference, Ath-ens, Greece, March 28, 2014