CXQU: A compact XML storage for efficient query and update processing

The volume of XML data is increasing rapidly. This poses challenges to the database community to find efficient XML data management solutions. Because XML is by nature verbose, compression is an important issue for XML. In this paper, we propose a new approach (CXQU) which not only supports efficient queries and updates but also compresses the structure of an XML document based on the exploitation of repetitive consecutive tags in the structure of the XML documents by using a labeling scheme derived from the ORDPATH labeling scheme. CXQU stores the compressed XML structure and the data separately in a robust compact storage that includes a set of access support structures to guarantee fast query performance and efficient updates, especially insertion. An experimental evaluation on sets of XML data shows the efficiency of CXQU.