数据库的规范化理论与非规范化设计

关系数据库设计的目标就是要得到一组关系模式来组成一个最优的数据库模式,使得我们既不必存储不必要的重复数据,又可以方便地查询数据。这组关系模式首先要用关系规范化理论规范化,构造好的逻辑结构,然后根据需要,从提高数据库性能的角度,进行非规范化处理。规范化和非规范化各有其优缺点,需要我们根据实际需求权衡处理。

Theory of Normalization and Demoralization of Database

The goal of designing relational database is to obtain the relational pattern to constitute a optimum database,which will enable us to query data conveniently and not to store rebundant and unnecessary data as well. This serial of relational pattern firstly will be normalized by the normalization theory and then from the perspective of increasing the property of the database,it will be processed antinormalization to meet different needs.Both normalization and antinormalization,having advantages and disadvantages,should be disposed according to practical needs.