RiBS Lab

Overview

There is a huge gap between the Semantic Web and Database community. However in recent years, we are starting to see interest from the Database community in the data management aspects of the Semantic Web. The databases to manage Semantic Web data, called triple stores, can be created using relational databases as the backend. However current triple-stores with relational backend have poor performance. The research problem is to identify other ways to take advantage of the existing relational database infrastructure.

Ultrawrap

Ultrawrap is an automatic Relational Database to RDF (RDB2RDF) system that implements a SPARQL query interface on legacy relational databases. A novel aspect of Ultrawrap is the virtualization of the relational data as RDF triple by defining it as an un-materialized SQL view and limiting SPARQL translation to SQL by simply substituting SPARQL algebra operators with their equivalent relational operators and execution the query on the SQL view. A result is the algorithmic challenge of rewriting SPARQL to equivalent SQL queries on the relational representation of the data is simply passed-off to the SQL optimizer. Since the data is not replicated, this organization assures real-time consistency between the relational and semantic web access. Our experimental results showed that our approach is better than other existing triple-stores.

People

• Juan F. Sequeda (Primary Contact)
• Daniel P. Miranker
• Syed H. Tirmizi

Collaborators

• Marcelo Arenas - Pontificia Universidad Catolica de Chile
• Oscar Corcho - Universidad Politecnica de Madrid, Spain
• Conor Cunningham - Microsoft

Alumni

• Rudy Depena
• Guillermo Cabrera

Publications

• Sequeda, J F. Depena, R. Miranker, D. (2009) Ultrawrap: Using SQL Views for RDB2RDF. Poster in the 8th International Semantic Web Conference (ISWC2009). Washington DC, US [pdf] [Poster]
• Sequeda, J F. Garcia-Castro, A. Corcho, O. Tirmizi, S. Miranker, D. (2009) Overcoming database heterogeneity to facilitate social networks: the Colombian displaced population as a case study. Invited Paper at the 18th World Wide Web Conference (WWW2009). WWW in Iberoamerica Track. Madrid, Spain [pdf]
• Sahoo, S. Halb, W. Hellmann, S. Idehen, K. Thibodeau, T. Auer, S. Sequeda, J F. Ezzat, A. (2009)A Survey of Current Approaches for Mapping of Relational Databases to RDF . W3C RDB2RDF XG Report [pdf]
• Sequeda, J F. Trimizi, S.H. Corcho, O. Miranker, D.P. (2009) Direct Mapping SQL Databases to the Semantic Web. Technical Report 09-04. The University of Texas at Austin, Department of Computer Sciences. [pdf]
• Sequeda, J F. Tirmizi, S. Miranker, D. (2008) A Bootrstrapping Architecture for Integration of Relational Databases to the Semantic Web. Poster in the 7th International Semantic Web Conference (ISWC2008). Karlsruhe, Germany [pdf] [Poster]
• Tirmizi, S. Sequeda, J F. Miranker, D. (2008) Translating SQL Applications to the Semantic Web. In Proceedings of the 19th International Databases and Expert Systems Application Conference (DEXA2008). Turin, Italy [pdf]
• Sequeda, J F. Tirmizi, S. Miranker, D. (2007) SQL Databases are a Moving Target. Position Paper for W3C Workshop on RDF Access to Relational Databases. Cambridge, MA, USA [pdf]