XML compression

To effectively reduce the redundancy and verbosity of XML data, various studies for XML compression have been conducted. Especially, XML data management systems and applications require the support of direct query processing and update on compressed XML data, the stream based compression/decompression, and the reduction of the size of the compressed data. In order to fully support the various aspects of XML compression, existing XML compression techniques should be carefully examined and the additional requirements for XML compression techniques should be considered. In this chapter, the authors first classify existing representative XML compression techniques according to their characteristics. Second, they explain the details of XML specific compression techniques. Third, they summarize the performance of the compression techniques in terms of the compression ratio and the compression and decompression time. Lastly, they present some future research directions.