A Low-Storage-Consumption XML Labeling Method for Efficient Structural Information Extraction

  • Wenxin Liang
  • Akihiro Takahashi
  • Haruo Yokota
Part of the Lecture Notes in Computer Science book series (LNCS, volume 5690)


Recently, labeling methods to extract and reconstruct the structural information of XML data, which are important for many applications such as XPath query and keyword search, are becoming more attractive. To achieve efficient structural information extraction, in this paper we propose C-DO-VLEI code, a novel update-friendly bit-vector encoding scheme, based on register-length bit operations combining with the properties of Dewey Order numbers, which cannot be implemented in other relevant existing schemes such as ORDPATH. Meanwhile, the proposed method also achieves lower storage consumption because it does not require either prefix schema or any reserved codes for node insertion. We performed experiments to evaluate and compare the performance and storage consumption of the proposed method with those of the ORDPATH method. Experimental results show that the execution times for extracting depth information and parent node labels using the C-DO-VLEI code are about 25% and 15% less, respectively, and the average label size using the C-DO-VLEI code is about 24% smaller, comparing with ORDPATH.


Keyword Search Ancestor Node XPath Query Context Node Label Size 
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 2009

Authors and Affiliations

  • Wenxin Liang
    • 1
  • Akihiro Takahashi
    • 2
  • Haruo Yokota
    • 2
    • 3
  1. 1.School of SoftwareDalian University of TechnologyChina
  2. 2.Department of Computer ScienceTokyo Institute of TechnologyJapan
  3. 3.Global Scientific Information and Computing CenterTokyo Institute of TechnologyJapan

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