Integrating a Maximum-Entropy Cardinality Estimator into DB2 UDB

  • Marcel Kutsch
  • Peter J. Haas
  • Volker Markl
  • Nimrod Megiddo
  • Tam Minh Tran
Part of the Lecture Notes in Computer Science book series (LNCS, volume 3896)

Abstract

When comparing alternative query execution plans (qeps), a cost-based query optimizer in a relational database management system (rdbms) needs to estimate the selectivity of conjunctive predicates. The optimizer immediately faces a challenging problem: how to combine available partial information about selectivities in a consistent and comprehensive manner [1]. This paper describes a prototype solution to this problem.

Keywords

Relational Database Management System Selectivity Estimate Maximum Entropy Distribution Iterative Scaling Inconsistency Resolution 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

  1. 1.
    Markl, V., Megiddo, N., Kutsch, M., Tran, T.M., Haas, P.J., Srivastava, U.: Consistently estimating the selectivity of conjuncts of predicates. In: Proc 31st VLDB, pp. 373–384 (2005)Google Scholar
  2. 2.
    Ilyas, I.F., Markl, V., Haas, P.J., Brown, P.G., Aboulnaga, A.: CORDS: Automatic discovery of correlations and soft functional dependencies. In: Proc. ACM SIGMOD, pp. 647–658 (2004)Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • Marcel Kutsch
    • 1
  • Peter J. Haas
    • 2
  • Volker Markl
    • 2
  • Nimrod Megiddo
    • 2
  • Tam Minh Tran
    • 3
  1. 1.IBM Boeblingen LaboratoryBoeblingenGermany
  2. 2.IBM Almaden Research CenterSan JoseUSA
  3. 3.IBM Silicon Valley Research LaboratorySan JoseUSA

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