不同类别不同字段怎么实现?
不同类别不同字段如何实现??
1. 如阿里巴巴发布产品时,当选择不同的类别时,对应的不同的产品字段发布, 这个逻辑关系是如何实现的, 数据表是怎么建立的,会的请帮忙!谢了
------解决方案--------------------
这里的关键在怎么建立产品字段表,按照需求你需要竖向建立。
你可以这样建。
id :自增id
category : 产品类别
name : 产品字段
其中一个一个产品类别可以对应多个产品字段。
------解决方案--------------------
需求分析啊!建表你如果没有思路的话就一步步的来啊!
求人不如求自己!
你先发各个对象的属性还有各自的关系吧关系图做出来!
然后按照3个基本的范式进行建表就可以了!
------解决方案--------------------
EAV模式,
1 产品基本信息表;
2 产品分类与字段关系表;
3 所有字段表;
4 产品字段值表;

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