DBMS techniques for lightweight computing devices

Lightweight computing devices are becoming ubiquitous and an increasing number of applications are being developed for these devices. Many applications deal with a significant amount of data and involve complex joins and aggregate operations which necessitate a local database management system on the device. However, scaling down the DBMS is a challenge as these devices are constrained by limited stable storage and main memory. Optimum utilization of these limited resources is a must for such a database system. New storage models that reduce storage costs are needed and the best storage scheme should be selected based on data characteristics and nature of queries. Memory should be optimally allocated among the database operators and the best query plan should be chosen depending on the amount of available memory and the underlying storage scheme. We propose a novel storage model, ID based Storage, which reduces storage costs considerably. We present an exact algorithm for allocating memory among the database operators. Due to its high complexity, we also propose a heuristic solution based on the benefit of an operator per unit memory allocation. Our storage management and query processing strategy ensures the best storage scheme and query execution plan for a given handheld device.