Abstract: In mobile database systems, new features such as mobility, disconnection and long lived transactions make traditional transaction processing schemes no longer suited. An extended optimistic two-phase commit transaction model（EO2PC-MT） is proposed, the model incorporates the design idea of the 02PC-MT model, solves the problem of unnecessary transaction aborts caused by the momentary communication failure and the mobile transaction coordinator failure result in obstruction. The experiment results show that the EO2PC-MT model outperforms the previously proposed mobile transaction models such as O2PC-MT for mobile transaction processing.

Key words: mobile database, transaction processing, optimistic concurrency control, two-phase commit

摘要： 在移动数据库系统中，事务的移动性、频繁断接性以及长事务等特性使得传统的事务处理模式不再适用。提出一种扩展的乐观两阶段提交事务处理模型（O2PC-MT），该模型吸收了O2PC-MT模型的设计思想，解决了由短暂的通信失效造成不必要的事务中止以及移动事务协调器故障导致的阻塞等问题。实验结果表明，与O2PC-MT事务处理模型相比，EO2PC-MT提高了系统的事务吞吐率以及改善了系统的总体性能。

关键词: 移动数据库, 事务处理, 乐观并发控制, 两阶段提交