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数据库表设计
Home Database Mysql Tutorial 数据库表设计--动态字段

数据库表设计--动态字段

Jun 07, 2016 pm 02:59 PM
Several dynamic Field database design

数据库表设计 当对象是动态的增加时的几种设计 : 1. 在表中预留字段 . 这种做法效率高 , 但预览字段个数不知道要多少合适 . 2. 动态的在表中创建字段 . 一般安全的系统是不容许这样做的 . 3. 利用动态属性表配置 . 增加属性表 , 和属性值表 . 欢迎大家讨论。

数据库表设计

当对象是动态的增加时的几种设计:

1.        在表中预留字段. 这种做法效率高,但预览字段个数不知道要多少合适.

2.       动态的在表中创建字段一般安全的系统是不容许这样做的.

3.       利用动态属性表配置. 增加属性表,和属性值表.

 

欢迎大家讨论。从,方便性,灵活性,高效性(性能),安全性,合理性,面向对象性等方面探讨说明。

后面有时间我会补充完整。


今天又看到一篇文章: http://blog.sina.com.cn/s/blog_85295a390101dou0.html


决定采用主表中增加一个字段的形式,搜索以后可以通过搜索引擎来做。或者采用复合方案。

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