pdm画表间结构

PDM(物理概念模型)各种属性建立如PK,AK等

https://blog.csdn.net/qq_27376871/article/details/51321609

CDM: ER图详细教程

通常在概要设计阶段，画er图，是现实世界中数据特征的抽象

https://www.cnblogs.com/yingsong/p/5072375.html

https://blog.csdn.net/dingguagua99/article/details/51317091

PowerDesigner连接mysql逆向生成pdm

https://www.cnblogs.com/dennyzhangdd/p/5550868.html