数据库建模 : 概念模型 , 逻辑模型和物理模型

转载：https://blog.csdn.net/tojohnonly/article/details/88343166?spm=1001.2101.3001.6650.19&utm_medium=distribute.pc_relevant.none-task-blog-2%7Edefault%7EBlogCommendFromBaidu%7ERate-19.pc_relevant_paycolumn_v3&depth_1-utm_source=distribute.pc_relevant.none-task-blog-2%7Edefault%7EBlogCommendFromBaidu%7ERate-19.pc_relevant_paycolumn_v3&utm_relevant_index=21