农田信息系统中时态数据冗余问题的研究

Research on temporal data redundancy of manage information system for formland

数据冗余问题一直是时态关系数据库存储时不可避免的问题。分析了几种时态关系模型在数据存储上的缺陷,结合函数依赖的概念和时态关系模型。在以时态函数依赖度为依据的基础上提出了一种时态函数依赖关系模型,并将此模型成功应用于农田信系统中,使农田信息数据冗余大量减少,并在一定程度上缩短了数据库操作查询时间,提高了效率。

Data redundancy has been the inevitable problems when the database storage of temporal relationship.Analyed several defect of temporal relationship model in the data storage.With the concept of functional dependency and temporal relationship model,on the basic of the degree of temporal functional depedency,proposed a model of temporal functional dependency.This is successfully applied to the agricultural information management system.Reduced the amount of data redundancy on the file information.And to some extent,this model cut down the time of database query,improved the search efficiency.