Estimating Costs of Path Expression Evaluation in Distributed Object Databases

  • Gabriela Ruberg
  • Fernanda Baião
  • Marta Mattoso
Conference paper

DOI: 10.1007/3-540-46146-9_35

Part of the Lecture Notes in Computer Science book series (LNCS, volume 2453)
Cite this paper as:
Ruberg G., Baião F., Mattoso M. (2002) Estimating Costs of Path Expression Evaluation in Distributed Object Databases. In: Hameurlain A., Cicchetti R., Traunmüller R. (eds) Database and Expert Systems Applications. DEXA 2002. Lecture Notes in Computer Science, vol 2453. Springer, Berlin, Heidelberg

Abstract

Efficient evaluation of path expressions in distributed object databases involves choosing among several query processing strategies, due to the rich semantics involved in object-based data models and to the complexity added by the distribution. This work presents a new cost model for object-based query processors and addresses relevant issues, which are ignored or relaxed in other works in the literature, such as the selectivity of the path expression, the sharing degree of the referenced objects, the partial participation of the collections in the relationships, and the distribution of the database objects across the nodes of a network. These issues allowed us to present more realistic estimates for the query optimizer. Our cost model has been validated against experimental results obtained with an object DBMS prototype running in a distributed architecture, using the OO7 benchmark application.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2002

Authors and Affiliations

  • Gabriela Ruberg
    • 1
  • Fernanda Baião
    • 1
  • Marta Mattoso
    • 1
  1. 1.Department of Computer ScienceCOPPE/UFRJRio de JaneiroBrazil

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