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Partial-match retrieval for dynamic files using linear hashing with partial expansions

  • Kotagiri Ramamohanarao
  • John Shepherd
  • Ron Sacks-Davis
Basic Data Structures
Part of the Lecture Notes in Computer Science book series (LNCS, volume 367)

Abstract

The average number of disk accesses required to perform primary-key retrieval in systems using linear hasing can be reduced by employing the technique of partial expansions. This scheme maintains a more uniform distribution of records amongst the pages of the database file, thus reducing the average length of overflow chains and hence the average query cost. In this paper, we analyse the cost benefits of using linear hashing with partial expansions for partial-match retrieval and show that this type of indexing is effective for use with partial-match retrieval on highly dynamic files.

Keywords

Home Page Average Cost File Size Split Pointer Query Type 
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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Copyright information

© Springer-Verlag Berlin Heidelberg 1989

Authors and Affiliations

  • Kotagiri Ramamohanarao
    • 1
  • John Shepherd
    • 1
  • Ron Sacks-Davis
    • 2
  1. 1.Department of Computer ScienceThe University of MelbourneParkvilleAustralia
  2. 2.Department of Computer ScienceRoyal Melbourne Institute of TechnologyMelbourneAustralia

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