A Path-based Approach for Efficient Evaluation of Twig Queries over XML Data *

Efficient XML query processing has been a critical issue for these days. In this paper, a path-based approach is proposed to process XML queries which can be represented as a query tree with twig patterns. We summarize and encode all the possible paths in the XML data in advance, so that we could efficiently determine where the physical paths, which satisfy the constraint of individual path expressions in the input query, need to be "glued" to form the final correct match. We have conducted a series of experiments to evaluate the performance of the proposed system. The results show that our approach has a great advantage over the state-of-the-art element-based or hybrid approach.