分布式云数据库复合Trigger新机制

A Flexible Trigger Mechanism in Cloud Database

为灵活高效地解决在不同的场景下,更新云数据库系统中缓存的全局共享数据表的问题,本文提出了一种在云服务端分布式数据库使用的复合触发器新型的软件架构,并基于数据库触发器技术,引入了直接、间接和复合Trigger的3种机制,这3种Trigger机制的引用,使来自业务支撑模块的数据变化,或是实时业务模块的数据变化,其前端的应用程序都可以及时高效的更新缓存。该研究提高了系统的灵活性,稳定性和鲁棒性。特别复合Trigger机制,可以避免大量的跨网络数据交互发生,提高了应用的服务质量。

In order to provide cache update flexibility under many different scenarios, this paper proposes a software architecture which uses 3 kinds of trigger mechanisms on global data tables in cloud distributed system, including direct trigger, indirect trigger and mixed trigger, which are based on database＇s trigger mechanism. Through these 3 mechanisms, service applications can get notifications no matter the data change comes from provisioning module or real time logic or the third-party interfaces. It is more flexible for designer to choose which trigger（s） to use per table itself characteristic. It will also improve the sys- tem＇s flexibility, stability and robustness. Especially, the mixed trigger can improve the quality of service and avoid the big WAN traffic that caused by reloading unconditionally under some defense scenarios.