Efficient queries over web views

  • Giansalvatore Mecca
  • Alberto O. Mendelzon
  • Paolo Merialdo
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1377)

Abstract

Large web sites are becoming repositories of structured information that can benefit from being viewed and queried as relational databases. However, querying these views efficiently requires new techniques. Data usually resides at a remote site and is organized as a set of related HTML documents, with network access being a primary cost factor in query evaluation. This cost can be reduced by exploiting the redundancy often found in site design. We use a simple data model, a subset of the Araneus data model, to describe the structure of a web site. We augment the model with link and inclusion constraints that capture the redundancies in the site. We map relational views of a site to a navigational algebra and show how to use the constraints to rewrite algebraic expressions, reducing the number of network accesses.

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References

  1. 1.
    S. Abiteboul and V. Vianu. Regular path queries with constraints. In PODS'97.Google Scholar
  2. 2.
    G. O. Arocena and A. O. Mendelzon. WebOQL: Restructuring documents, databases and Webs. In ICDE'98, 1998.Google Scholar
  3. 3.
    P. Atzeni and G. Mecca. Cut and Paste. In PODS'97.Google Scholar
  4. 4.
    P. Atzeni, G. Mecca, and P. Merialdo. To Weave the Web. In VLDB'97.Google Scholar
  5. 5.
    C. Beeri and Y. Kornatzky. Algebraic optimization of object-oriented query languages. In ICDT'90.Google Scholar
  6. 6.
    S. Cluet and C. Delobel. A general framework for the optimization of object-oriented queries. In SIGMOD'82.Google Scholar
  7. 7.
    B. P. Jenq, D. Woelk, W. Kim, and W. Lee. Query processing in distributed ORION. In EDBT'90.Google Scholar
  8. 8.
    A. Kemper and G. Moerkotte. Access support relations: An indexing method for object bases. Information Systems, 17(2):117–145, 1992.CrossRefGoogle Scholar
  9. 9.
    M. Ley. Database systems and logic programming bibliography site, http://-www.informatik.uni-trier.de/~ley/db/index.html.Google Scholar
  10. 10.
    G. Mecca, A. Mendelzon, and P. Merialdo. Efficient queries over Web views. Technical Report n. RT-DIA-31-1998, Dipartimento di Informatica e Automazione, Università di Roma Tre, 1998. http://poincare.dia.uniroma3.it:8080/Araneus/.Google Scholar
  11. 11.
    A. Mendelzon, G. Mihaila, and T. Milo. Querying the World Wide Web. Journal of Digital Libraries, 1(1):54–67, April 1997.Google Scholar
  12. 12.
    C. Mohan, D. Haderle, Y. Wang, and J. Cheng. Single table access using multiple indexes: Optimization, execution, and concurrency control techniques. In EDBT'90.Google Scholar
  13. 13.
    S. Navathe. An intuitive view to normalize network structured data. In VLDB'80.Google Scholar
  14. 14.
    M. T. özsu and J. A. Blakeley. Query processing in object-oriented database systems. In W. Kim, editor, Modern Database Management — Object-Oriented and Multidatabase Technologies, pages 146–174. Addison Wesley-ACM Press, 1994.Google Scholar
  15. 15.
    A. Rosenthal and D. S. Reiner. An architecture for query optimization. In SIGMOD, 1982.Google Scholar
  16. 16.
    A. Rosenthal and D. S. Reiner. Querying relational views of networks. In W. Kim, D. S. Reiner, and D. S. Batory, editors, Query Processing in Database Systems, pages 109–124. Springer-Verlag, 1985.Google Scholar
  17. 17.
    M.A. Roth, H.F. Korth, and A. Silberschatz. Extended algebra and calculus for 1NF relational databases. ACM TODS, 13(4):389–417, December 1988.CrossRefMathSciNetGoogle Scholar
  18. 18.
    G. M. Shaw and S. B. Zdonik. An object-oriented query algebra. In DBPL'89.Google Scholar
  19. 19.
    P. Valduriez. Join indices. ACM TODS, 12(2):218–246, 1987.CrossRefGoogle Scholar
  20. 20.
    Xie Z. and Han J. Join index hierarchies for supporting efficient navigations in object-oriented databases. In VLDB'94.Google Scholar
  21. 21.
    C. Zaniolo. Design of relational views over network schemas. In SIGMOD 1979.Google Scholar
  22. 22.
    C. Zaniolo. The database language GEM. In SIGMOD 1983.Google Scholar

Copyright information

© Springer-Verlag 1998

Authors and Affiliations

  • Giansalvatore Mecca
    • 1
  • Alberto O. Mendelzon
    • 2
  • Paolo Merialdo
    • 3
  1. 1.DIFAUniversità della BasilicataPotenzaItaly
  2. 2.Dept. of Computer ScienceUniversity of TorontoCanada
  3. 3.Dip. Informatica e AutomazioneUniversità di Roma TreRomaItaly

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