This book constitutes the refereed proceedings of the 9th International Conference on Database Systems for Advanced Applications, DASFAA 2004, held in Jeju Island, Korea in March 2004.

The 60 revised full papers and 18 revised short papers presented together with 2 invited articles were carefully reviewed and seleted from 272 submissions. The papers are organized in topical sections on access methods, query processing in XML, security and integrity, query processing in temporal and spatial databases, semi-structured databases, knowledge discovery in temporal and spatial databases, XML and multimedia and knowledge discovery on the Web, query processing and optimization, classification and clustering, Web search, mobile databases, parallel and distributed databases, and multimedia databases.