SPARQL for a Web of Linked Data: Semantics and Computability

  • Olaf Hartig
Part of the Lecture Notes in Computer Science book series (LNCS, volume 7295)

Abstract

The World Wide Web currently evolves into a Web of Linked Data where content providers publish and link data as they have done with hypertext for the last 20 years. While the declarative query language SPARQL is the de facto for querying a-priory defined sets of data from the Web, no language exists for querying the Web of Linked Data itself. However, it seems natural to ask whether SPARQL is also suitable for such a purpose

In this paper we formally investigate the applicability of SPARQL as a query language for Linked Data on the Web. In particular, we study two query models: 1) a full-Web semantics where the scope of a query is the complete set of Linked Data on the Web and 2) a family of reachability-based semantics which restrict the scope to data that is reachable by traversing certain data links. For both models we discuss properties such as monotonicity and computability as well as the implications of querying aWeb that is infinitely large due to data generating servers.

References

  1. 1.
    Abiteboul, S., Vianu, V.: Queries and computation on the web. Theoretical Computer Science 239(2) (2000)Google Scholar
  2. 2.
    Angles, R., Gutierrez, C.: The Expressive Power of SPARQL. In: Sheth, A.P., Staab, S., Dean, M., Paolucci, M., Maynard, D., Finin, T., Thirunarayan, K. (eds.) ISWC 2008. LNCS, vol. 5318, pp. 114–129. Springer, Heidelberg (2008)CrossRefGoogle Scholar
  3. 3.
    Arenas, M., Pérez, J.: Querying Semantic Web Data with SPARQL. In: PODS (2011)Google Scholar
  4. 4.
    Auer, S., Lehmann, J., Hellmann, S.: LinkedGeoData: Adding a Spatial Dimension to the Web of Data. In: Bernstein, A., Karger, D.R., Heath, T., Feigenbaum, L., Maynard, D., Motta, E., Thirunarayan, K. (eds.) ISWC 2009. LNCS, vol. 5823, pp. 731–746. Springer, Heidelberg (2009)CrossRefGoogle Scholar
  5. 5.
    Berners-Lee, T.: Linked Data (2006), http://www.w3.org/DesignIssues/LinkedData.html
  6. 6.
    Bizer, C., Heath, T., Berners-Lee, T.: Linked Data – the story so far. Journal on Semantic Web and Information Systems 5(3) (2009)Google Scholar
  7. 7.
    Bouquet, P., Ghidini, C., Serafini, L.: Querying the Web of Data: A Formal Approach. In: Gómez-Pérez, A., Yu, Y., Ding, Y. (eds.) ASWC 2009. LNCS, vol. 5926, pp. 291–305. Springer, Heidelberg (2009)CrossRefGoogle Scholar
  8. 8.
    Florescu, D., Levy, A.Y., Mendelzon, A.O.: Database techniques for the world-wide web: A survey. SIGMOD Record 27(3) (1998)Google Scholar
  9. 9.
    Harth, A., Hose, K., Karnstedt, M., Polleres, A., Sattler, K.-U., Umbrich, J.: Data Summaries for On-Demand Queries over Linked Data. In: WWW (2010)Google Scholar
  10. 10.
    Hartig, O.: Zero-Knowledge Query Planning for an Iterator Implementation of Link Traversal Based Query Execution. In: Antoniou, G., Grobelnik, M., Simperl, E., Parsia, B., Plexousakis, D., De Leenheer, P., Pan, J. (eds.) ESWC 2011, Part I. LNCS, vol. 6643, pp. 154–169. Springer, Heidelberg (2011)CrossRefGoogle Scholar
  11. 11.
    Hartig, O.: SPARQL for a Web of Linked Data: Semantics and Computability (Extended Version). CoRR abs/1203.1569 (2012), http://arxiv.org/abs/1203.1569
  12. 12.
    Hartig, O., Bizer, C., Freytag, J.-C.: Executing SPARQL Queries over the Web of Linked Data. In: Bernstein, A., Karger, D.R., Heath, T., Feigenbaum, L., Maynard, D., Motta, E., Thirunarayan, K. (eds.) ISWC 2009. LNCS, vol. 5823, pp. 293–309. Springer, Heidelberg (2009)CrossRefGoogle Scholar
  13. 13.
    Ladwig, G., Tran, T.: Linked Data Query Processing Strategies. In: Patel-Schneider, P.F., Pan, Y., Hitzler, P., Mika, P., Zhang, L., Pan, J.Z., Horrocks, I., Glimm, B. (eds.) ISWC 2010, Part I. LNCS, vol. 6496, pp. 453–469. Springer, Heidelberg (2010)CrossRefGoogle Scholar
  14. 14.
    Ladwig, G., Tran, T.: SIHJoin: Querying Remote and Local Linked Data. In: Antoniou, G., Grobelnik, M., Simperl, E., Parsia, B., Plexousakis, D., De Leenheer, P., Pan, J. (eds.) ESWC 2011, Part I. LNCS, vol. 6643, pp. 139–153. Springer, Heidelberg (2011)CrossRefGoogle Scholar
  15. 15.
    Mendelzon, A.O., Milo, T.: Formal models of web queries. Inf. Systems 23(8) (1998)Google Scholar
  16. 16.
    Pérez, J., Arenas, M., Gutierrez, C.: Semantics and complexity of SPARQL. ACM Transactions on Database Systems 34(3) (2009)Google Scholar
  17. 17.
    Picalausa, F., Vansummeren, S.: What are real SPARQL queries like? In: SWIM (2011)Google Scholar
  18. 18.
    Schmidt, M., Meier, M., Lausen, G.: Foundations of sparql query optimization. In: Proc. of the 13th Int. Conference on Database Theory, ICDT (2010)Google Scholar
  19. 19.
    Vrandecić, D., Krötzsch, M., Rudolph, S., Lösch, U.: Leveraging non-lexical knowledge for the linked open data web. In: RAFT (2010)Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  • Olaf Hartig
    • 1
  1. 1.Humboldt-Universität zu BerlinGermany

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