EDB system was designed by module and hierarchy. According the level of operation, the system can be divided by Interface Layer, Engine Layer-. Access Layer, Service Layer and Store Layer.

• EDB系统采取了模块化和层次化的设计方式，根据操作的层次具体可分为接口处理层(Interface Layer)、数据库引擎层(Engine Layer)、数据存取层(Access Layer)、数据库维护层(Service Layer)和数据存储层(Store Layer)。