|Yianilos Laboratories||A Synchronizable Transactional Database|
Abstract: A database system that can efficiently synchronize all or a part of its contents over a limited bandwidth link is described. The lowest layer of the system implements a transactional block store of novel design. On top of this is a new enhanced form of B+-tree that can efficiently compute a digest(hash) of the records within any range of key values in $O(\log n)$ time. The top level is a communication protocol that directs the synchronization process so that minimization of bits communicated, rounds of communication, and local computation are simultaneously addressed. The entire synchronizable database is experimentally measured, and the results confirm our analysis. Experiments and comparisons are also reported for the system's two lower layers performing conventional database operations. Finally we suggest that our notion of a synchronizable transactional database, as well as our implementation, might serve as a building block for applications ranging from digital libraries to distributed file systems and electronic commerce.