PHP 中要如何避免关联表
PHP 中要如何处理关联表
- PHP code
<!-- Code highlighting produced by Actipro CodeHighlighter (freeware) http://www.CodeHighlighter.com/ --> 比如有 用户表 文章表 评论表 收藏表 例子 用户A,发表一文章,被用户B评论,被用户C收藏, 如果对用户A执行删除操作,A发表的文章,文章的评论,收藏要怎么处理 类似问题应该按什么原则进行处理? /*****************************************/ 另外,php如何实现关联表的操作~添加,更新,删除
------解决方案--------------------
文章删除后把相应的评论、收藏也删除就行了。
多表可以连接。比如left join/right join/inner join 建议去看看mysql多表操作。
------解决方案--------------------
多表的操作:把相关数据分表操作,一张一张表来;
只有查询的时候关联在一起查询。
http://user.qzone.qq.com/937461184/blog/1330412851
------解决方案--------------------
楼主可以看看mysql的联表删除,也就是当你删除文章的时候,也在删除评论,和收藏的文章。
------解决方案--------------------
如果你上传了文件,同时被用户评论,收藏。
你要是删掉这个文件。那么其他用户的评论,和收藏该不该有。这是先考虑的问题。
如果你觉得这些东西都删掉。那么根据id删除,或者建立触发器等等。
如果你觉得没必要删除,那。。

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