Summarisation for mobile databases

In mobile computing, issues such as limited resources, network capacities and organisational constraints may cause the complete replication of large databases on a mobile device to be infeasible. At the same time, some on-board storage of data is attractive as communication to the main database can be inconsistent. Thus, as the emphasis on application mobility increases, data summarisation offers a useful solution to improving response times and the availability of data. These summarisation techniques can also be of benefit to distributed databases, particularly those with mobile components or where the profile of the transaction load varies significantly over time. This paper surveys summarisation techniques used for mobile distributed databases. It also surveys the manner in which database functionality is maintained in mobile database systems, including query processing, data replication, concurrency control, transaction support and system recovery. Classification: H.2 (Database Management), H.3.2 (Information Storage).