Processing XML Twig Pattern Query with Wildcards
- Cite this paper as:
- Wu H., Lin C., Ling T.W., Lu J. (2012) Processing XML Twig Pattern Query with Wildcards. In: Liddle S.W., Schewe KD., Tjoa A.M., Zhou X. (eds) Database and Expert Systems Applications. DEXA 2012. Lecture Notes in Computer Science, vol 7446. Springer, Berlin, Heidelberg
In this paper, we present a novel and complementary technique to optimize XML twig pattern queries with wildcards(*). Our approach is based on utilizing a new axis called AD-dis, to equivalently rewrite a query with wildcards (non-branching as well as branching wildcards) into a single query without any wildcards. We present efficient rewriting algorithms and also twig pattern matching algorithms to process the rewritten queries with AD-dis, which is proven to be I/O and CPU optimal. In addition, the experimental results not only verify the scalability and efficiency of our extended matching algorithms, but also demonstrate the effectiveness of our rewriting algorithms.