In this study we address the problem of answering queries over information sources storing objects which are indexed by terms arranged in a taxonomy. We examine query languages of different expressivity and sources with different kinds of taxonomies. In the simplest kind, the taxonomy includes just term-to-term subsumption links. This case is used as a basis for further developments, in which we consider taxonomies consisting of term-to-queries links. An algorithm for query evaluation is presented for this kind of taxonomies, and it is shown that the addition of negation to the query language leads to intractability. Finally, query-to-query taxonomies are considered.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    Ling, B., Lu, Z., Ng, W.S., Ooi, B., Tan, K.L., Zhou, A.: A Content-Based Resource Location Mechanism in PeerIS. In: Proc. of the 3rd International Conference on Web Information Systems Engineering, WISE 2002, Singapore (2002)Google Scholar
  2. 2.
    Koubarakis, M., Tryfonopoulos, C.: Peer-to-Peer Agent Systems for Textual Information Dissemination: Algorithms and Complexity. In: Proceedings of the UK Workshop on Multiagent Systems, UKMAS 2002, Liverpool, UK (2002)Google Scholar
  3. 3.
    Tzitzikas, Y., Meghini, C., Spyratos, N.: Taxonomy-based Conceptual Modeling for Peer-to-Peer Networks. In: Song, I.-Y., Liddle, S.W., Ling, T.-W., Scheuermann, P. (eds.) ER 2003. LNCS, vol. 2813, pp. 446–460. Springer, Heidelberg (2003)CrossRefGoogle Scholar
  4. 4.
    Tzitzikas, Y., Spyratos, N., Constantopoulos, P.: Mediators over Taxonomy-based Information Sources. VLDB Journal (2004) (to appear)Google Scholar
  5. 5.
    Meghini, C., Tzitzikas, Y.: Query evaluation in peer-to-peer networks of taxonomybased sources. In: Meersman, R., Tari, Z., Schmidt, D.C. (eds.) CoopIS 2003, DOA 2003, and ODBASE 2003. LNCS, vol. 2888, pp. 263–281. Springer, Heidelberg (2003)CrossRefGoogle Scholar
  6. 6.
    Ceri, S., Gottlob, G., Tanca, L.: Logic Programming and Databases. Springer, Heidelberg (1990)Google Scholar
  7. 7.
    Ullman, J.D.: Principles of Database and Knowledge-Base Systems, vol. I. Computer Science Press, Rockville (1988)Google Scholar
  8. 8.
    Lenzerini, M.: Data integration: A theoretical perspective. In: Proceedings of PODS 2002, the twenty-first ACM SIGMOD-SIGACT-SIGART Symposium on Principles of Database Systems, Madison, Winsconsin, USA (2002)Google Scholar
  9. 9.
    Gribble, S., Halevy, A., Ives, Z., Rodrig, M., Suiu, D.: What can Databases do for Peer-to-Peer?. In: Proceedings of WebDB 2001, Santa Barbara, CA (2001)Google Scholar
  10. 10.
    Bernstein, P.A., Giunchiglia, F., Kementsietsidis, A., Mylopoulos, J., Serafini, L., Zaihrayeu, I.: Data Management for Peer-to-Peer Computing: A Vision. In: Proceedings of WebDB 2002, Madison, Wisconsin (2002)Google Scholar
  11. 11.
    Kementsietsidis, A., Arenas, M., Miller, R.J.: Mapping Data in Peer-to-Peer Systems: Semantics and Algorithmic Issues. In: Int. Conf. on Management of Data, SIGMOD 2003, San Diego, California (2003)Google Scholar
  12. 12.
    Nejdl, W., Wolf, B., Staab, S., Tane, J.: EDUTELLA: Searching and Annotating Resources within an RDF-based P2P Network. In: Semantic Web Workshop 2002, Honolulu, Havaii (2002)Google Scholar
  13. 13.
    Nejdl, W., Wolf, B., Qu, C., Decker, S., Sintek, M., Naeve, A., Nilsson, M., Palmer, M., Risch, T.: EDUTELLA: A P2P networking infrastructure based on RDF. In: WWW 2002 (2002)Google Scholar
  14. 14.
    Halevy, A., Ives, Z., Mork, P., Tatarinov, I.: Piazza: Data Management Infrastructure for Semantic Web Applications. In: Proceedings of WWW 2003 (2003)Google Scholar
  15. 15.
    Tzitzikas, Y., Meghini, C.: Ostensive Automatic Schema Mapping for Taxonomybased Peer-to-Peer Systems. In: Klusch, M., Omicini, A., Ossowski, S., Laamanen, H. (eds.) CIA 2003. LNCS (LNAI), vol. 2782, pp. 78–92. Springer, Heidelberg (2003)CrossRefGoogle Scholar
  16. 16.
    Cooper, B., Garcia-Molina, H.: Modeling and Measuring Scalable Peer-to-peer Search Networks. Technical report, University of Stanford (2002)Google Scholar
  17. 17.
    Yang, B., Garcia-Molina, H.: Comparing Hybrid Peer-to-Peer Systems. The VLDB Journal, 561–570 (2001)Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2004

Authors and Affiliations

  • Carlo Meghini
    • 1
  • Yannis Tzitzikas
    • 2
  1. 1.ISTI CNRPisaItaly
  2. 2.Institut d’InformatiqueUniversity of NamurBelgium

Personalised recommendations