The temporal data model of this system is provided, and the operation logic is defined, then the expression mode of the temporal database query is described, at last how to extract the temporal data by difference view and snapshot is detailedly introduced. 给出了该系统的时态数据模型,在此基础上定义了该时态数据的业务逻辑,描述了时态数据库查询的表示模式,最后详细介绍了如何通过快照和差异视图抽取时态数据。