Exploiting Path Indexes to Answer Complex Queries in Ontology Repository

The ontology repository has widely been used for storing and querying over ontology data. Recently the ontology repository gets more attentions as a component of ubiquitous systems. This paper describes use of the path index to answer complex queries in ontology repository. Studies show that two types of queries namely chain queries and star queries frequently occur in SPARQL queries. Instead of using join operations over several triple indexes, we proposed to use path indexes for such queries, which in turn improve the query performance reducing the number of multiple join operations. Our experiments show that the proposed method enhances the query performance than using only indexes based on single triple pattern.

[1]  Ehud Gudes,et al.  Exploiting local similarity for indexing paths in graph-structured data , 2002, Proceedings 18th International Conference on Data Engineering.

[2]  Xiaofeng Meng,et al.  HStar - A Semantic Repository for Large Scale OWL Documents , 2006, ASWC.

[3]  Jeff Heflin,et al.  DLDB: Extending Relational Databases to Support Semantic Web Queries , 2003, PSSS.

[4]  Dave Reynolds,et al.  Efficient RDF Storage and Retrieval in Jena2 , 2003, SWDB.

[5]  Stanislav Barton,et al.  Designing Indexing Structure for Discovering Relationships in RDF Graphs , 2004, DATESO.

[6]  Jeff Heflin,et al.  An Evaluation of Knowledge Base Systems for Large OWL Datasets , 2004, SEMWEB.

[7]  Philippe Flajolet,et al.  Digital Search Trees Revisited , 1986, SIAM J. Comput..

[8]  Jaeho Lee,et al.  The path index for query processing on RDF and RDF schema , 2005, The 7th International Conference on Advanced Communication Technology, 2005, ICACT 2005..

[9]  Toshiyuki Amagasa,et al.  An Indexing Scheme for RDF and RDF Schema based on Suffix Arrays , 2003, SWDB.

[10]  Gerhard Weikum,et al.  RDF-3X: a RISC-style engine for RDF , 2008, Proc. VLDB Endow..

[11]  Eugene W. Myers,et al.  Suffix arrays: a new method for on-line string searches , 1993, SODA '90.

[12]  Andreas Harth,et al.  Optimized index structures for querying RDF from the Web , 2005, Third Latin American Web Congress (LA-WEB'2005).

[13]  Michael J. Franklin,et al.  A Fast Index for Semistructured Data , 2001, VLDB.

[14]  Frank van Harmelen,et al.  Sesame: A Generic Architecture for Storing and Querying RDF and RDF Schema , 2002, SEMWEB.