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RDF Views

Introduction

RDF is a rapidly expanding web standard. As RDF data on the web is subject to frequent change, there is a need to incrementally maintain views, which describe resources of interest to a user. In this project, we have developed the concept of an RDF-database and developed sophisticated view maintenance algorithms that take the graph structure of RDF data into account in order to answer queries very efficiently. We have implemented a prototype and experimentally show that our algorithms are faster than using classical view maintenance algorithms on the relational representations of RDF databases.

RDF databases attempt to track the massive amounts of web data and services available. We have developed the notion of an aggregate operation for RDF data. We show that a commercial RDF language called RDQL can be extended to support aggregations. We propose an efficient algorithm to compute answers to aggregate queries over RDF databases and a set of algorithms to maintain views involving those aggregates. We experimentally compare our algorithms with standard relational aggregate queries and view maintenance methods and show that our algorithms that operate directly on the RDF representation exhibit superior performance.

People

Edward Hung, Yu Deng, V.S. Subrahmanian

Publications

  1. Edward Hung, Yu Deng and V.S. Subrahmanian. RDF Aggregate Queries and Views. In Proceedings of the 21st International Conference on Data Engineering (ICDE 2005), Tokyo, Japan, April 5-8, 2005.

  2. Edward Hung, Yu Deng and V.S. Subrahmanian. RDF Aggregate Queries and Views. Technical Report UMCP-CSD CS-TR-4611 (UMIACS-TR-2004-53). August 2004.

  3. Edward Hung, Yu Deng and V.S. Subrahmanian. Maintaining RDF Views. Technical Report UMCP-CSD CS-TR-4612 (UMIACS-TR-2004-54). August 2004.

Presentations

  • Edward Hung, "RDF Aggregate Queries and Views," the 21st International Conference on Data Engineering (ICDE 2005), April 2005. (powerpoint)
Last updated: March 26 2008
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