MQX: multi-query engine for compressed XML data

1. OVERVIEW XML data are verbose due to their repeated tags and structures. Previous work has studied the techniques for efficient evaluation path expressions on original XML document [1] or single-query processing on compressed data [4] based on the different XML compression methods. However, it is still not clear how to exploit the existing XML compression techniques to evaluate multi-query and optimization strategies in XML subscribe/dissemination applications [2]. In this demonstration, we present MQX which is capable of processing multiple subscribed XPath query over compressed XML data. Different from most information retrieval or filtering systems which return the whole document, MQX obtains the matched XML elements, which is a fragment of the whole document.