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Journal of Computer Science and Technology

, Volume 10, Issue 2, pp 149–162 | Cite as

Optimization of multi-join queries in shared-nothing systems

  • Kian -Lee Tan
Regular Papers
  • 15 Downloads

Abstract

This paper proposes a semi-greedy framework for optimizing multi-join queries in shared-nothing systems. The plan generated by the framework comprises several pipelines, each performing several joins. The framework determines the “optimal” number of joins to be performed in each pipeline. The decisions are made based on the cost estimation of the entire processing plan. Two existing optimization algorithms are extended under the framework. An analytical model is presented and used to compare the quality of plans produced by each optimization algorithm. Our study shows that the new algorithms outperform their counterparts that are not extended.

Keywords

Multi-join optimization shared-nothing systems pipelining hash join segmented right-deep tree 

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Copyright information

© Science Press, Beijing China and Allerton Press Inc. 1995

Authors and Affiliations

  • Kian -Lee Tan
    • 1
  1. 1.Department of Information Systems and Computer ScienceNational University of SingaporeSingapore

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