SCEND: An Efficient Semantic Cache to Adequately Explore Answerability of Views

  • Guoliang Li
  • Jianhua Feng
  • Na Ta
  • Yong Zhang
  • Lizhu Zhou
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4255)


Maintaining a semantic cache of materialized XPath views inside or outside the database, is a novel, feasible and efficient approach to accelerate XML query processing. However, the main problems of existing approaches are that, they either can not exploit sufficient potential cached views to answer an issued query or need too much time for cache lookup. In this paper, we propose, SCEND, an efficient Semantic Cache based on dEcompositioN and Divisibility, which adequately explores the answerability of views, and speeds up cache lookup dramatically. We decompose complex XPath queries into some much simpler and tractable ones to improve cache hit rate, moreover, we introduce a notion of the divisibility between two positive integers to accelerate cache lookup. In addition, we present a new replacement technique for SCEND to improve performance for caching. We experimentally demonstrate the efficiency of our caching techniques and performance gains obtained by employing such a cache.


Tree Pattern Conjunctive Query View Versus XPath Query View Selection 
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 2006

Authors and Affiliations

  • Guoliang Li
    • 1
  • Jianhua Feng
    • 1
  • Na Ta
    • 1
  • Yong Zhang
    • 1
  • Lizhu Zhou
    • 1
  1. 1.Department of Computer Science and TechnologyTsinghua UniversityBeijingChina

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