Departmental Papers (CIS)

Date of this Version

June 2004

Document Type

Conference Paper


Copyright ACM, 2004. This is the author's version of the work. It is posted here by permission of ACM for your personal use. Not for redistribution. The definitive version was published in Proceedings of the 2004 ACM SIGMOD International Conference on Management of Data 2004, pages 47-58.
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We present BLAS, a Bi-LAbeling based System, for efficiently processing complex XPath queries over XML data. BLAS uses P-labeling to process queries involving consecutive child axes, and D-labeling to process queries involving descendant axes traversal. The XML data is stored in labeled form, and indexed to optimize descendent axis traversals. Three algorithms are presented for translating complex XPath queries to SQL expressions, and two alternate query engines are provided. Experimental results demonstrate that the BLAS system has a substantial performance improvement compared to traditional XPath processing using D-labeling.



Date Posted: 07 May 2005