关键词: 移动数据库, 关联事务结果集（UTLRSP）, 复制, 同步, 冲突处理, 动态新鲜度

Abstract: Synchronization is one of the key technologies in maintaining the consistency of replicated mobile database systems. The current mobile replication synchronization technology has many defects, such as the large amount of communication data and storage space consumption, especially, when the network bandwidth falls, it cannot update the client data timely, which lead to fail to perform mobile transactions. In order to solve the above shortcomings, the paper adopts UTLRSP（Union Transaction-Level Result-Set the Propagation） replication synchronization model combined with the data broadcasting technology, and by using the incremental updating algorithm based on priority to realize client and center database server data synchronization processing. Experimental results show that the model effectively reduces the consumption of client storage space and cuts down the communication costs compared with the two levels of replication mechanism. It associates the performing transaction with other transactions, and only saves transaction execution results. When the wireless network bandwidth falls, the algorithm prioritizes data according to the freshness. It ensures the highest freshness data transfer firstly. The algorithm improves the efficiency of data transmission, dynamic freshness and scalability for the client.

Key words: mobile database, Union Transaction-Level Result-Set the Propagation（UTLRSP）, replication, synchronization, conflict resolution, dynamic freshness