Semantic Query Optimization in an Automata-Algebra Combined XQuery Engine over XML Streams Hong Su, Elke A. Rundensteiner, and Murali Mani   View Paper (PDF)   Return to DEMO GROUP 3: XML Abstract Our raindrop system tackles challenges of stream processing that are particular to XML. This demo demonstrates two major aspects. First, it demonstrates the modeling issues, i.e., how to take advantage of both token-based automata paradigm and tuple-based algebraic paradigm for processing XQuery over XML streams. Second, it demonstrates the optimization issues, i.e., how to use schema knowledge to optimize an XQuery over XML streams based on our modeling. ©2005 Association for Computing Machinery