Compression Algorithms for Structural Query Results on XML Data

XML is an important data form. The size of query results on XML data is very large in some applications and in the distributed XML data management system, the transmission of query results become the bottleneck. For the efficiency of XML management system, the compression method for XML query results is studied in this paper. By exploiting the properties of query results on XML data, two compression methods are proposed. One is a G-bitmap algorithm as a variant of bitmap index. The other is based on tree structure. The experiments on real and manual data demonstrate the effectiveness and efficiency of our compression methods.