We present BLAS , a Bi-LAbeling based System, for efficiently processing complex XPath queries over XML data. BLAS uses Plabeling 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.
Yi Chen, Susan B. Davidson, Yifeng Zheng