A bi-labeling based XPath processing system

Yi Chen, Susan B. Davidson, Yifeng Zheng

Research output: Contribution to journalArticlepeer-review

9 Scopus citations


We present BLAS, a Bi-LAbeling based XPath processing System. BLAS uses two labeling schemes to speed up query processing: P-labeling for processing consecutive child (or parent) axis traversals, and D-labeling for processing descendant (or ancestor) axis traversals. XML data are stored in labeled form and indexed. Algorithms are presented for translating XPath queries to SQL expressions. BLAS reduces the number of joins in the SQL query translated from a given XPath query and reduces the number of disk accesses required to execute the SQL query compared with the traditional XPath processing using D-labeling alone. We also propose an approximate P-labeling scheme and the corresponding query translation algorithm to handle XML data trees that contain a large number of distinct tag names, and/or are very deep. This extension captures a spectrum of XPath-to-SQL query translation schemes, ranging from existing schemes that do not use P-labels to the one that uses exact P-labels. Experimental results demonstrate the efficiency of the BLAS system.

Original languageEnglish (US)
Pages (from-to)170-185
Number of pages16
JournalInformation Systems
Issue number2
StatePublished - Apr 2010
Externally publishedYes

All Science Journal Classification (ASJC) codes

  • Software
  • Information Systems
  • Hardware and Architecture


  • Query processing
  • XML
  • XPath


Dive into the research topics of 'A bi-labeling based XPath processing system'. Together they form a unique fingerprint.

Cite this