TJFast: effective processing of XML twig pattern matching

Finding all the occurrences of a twig pattern in an XML database is a core operation for efficient evaluation of XML queries. A number of algorithms have been proposed to process a twig query based on region encoding. In this paper, based on a novel labeling scheme: extended Dewey, we propose a novel and efficient holistic twig join algorithm, namely TJFast. Compared to previous work, our algorithm only needs to access the labels of leaf query nodes. We report our experimental results to show that our algorithms are superior to previous approaches in terms of the number of elements scanned and query performance.