TopX 2.0 at the INEX 2008 Efficiency Track

A (Very) Fast Object-Store for Top-k-Style XML Full-Text Search
  • Martin Theobald
  • Mohammed AbuJarour
  • Ralf Schenkel
Part of the Lecture Notes in Computer Science book series (LNCS, volume 5631)


For the INEX Efficiency Track 2008, we were just on time to finish and evaluate our brand-new TopX 2.0 prototype. Complementing our long-running effort on efficient top-k query processing on top of a relational back-end, we now switched to a compressed object-oriented storage for text-centric XML data with direct access to customized inverted files, along with a complete reimplementation of the engine in C++. Our INEX 2008 experiments demonstrate efficiency gains of up to a factor of 30 compared to the previous Java/JDBC-based TopX 1.0 implementation over a relational back-end. TopX 2.0 achieves overall runtimes of less than 51 seconds for the entire batch of 568 Efficiency Track topics in their content-and-structure (CAS) version and less than 29 seconds for the content-only (CO) version, respectively, using a top-15, focused (i.e., non-overlapping) retrieval mode—an average of merely 89 ms per CAS query and 49 ms per CO query.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2009

Authors and Affiliations

  • Martin Theobald
    • 1
  • Mohammed AbuJarour
    • 3
  • Ralf Schenkel
    • 1
    • 2
  1. 1.Max Planck Institute for InformaticsSaarbrückenGermany
  2. 2.Saarland UniversitySaarbrückenGermany
  3. 3.Hasso Plattner InstitutePotsdamGermany

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