评论表mySQL

Question

我想创建一个'评论'表，所以保存文本，创建，用户ID等...

但是用户可以评论很多事情。

所以我不能把'外部'表的外键，因为我也需要能够评论'图片'表，这是最佳做法是什么？

所以基本上是一个多表链接表？

Answer 1

评语表：

comment(comment_id,text, created, userid, other_field,...) 

链接表

link(comment_id,comment_type, refID,) 

其中comment_type将是你（ “图片”， “后”，...）评论表的名称。 comment_id将是用户所做评论的ID。​​是用户上（POST_ID，Picture_id，...）评论表的id

比方说你有这些表项：

POST(id, some_text,other_stuff,...): 
(1, "Hello Hello", "something",...) 
(2, "Hey there", "something_else",...) 
... 
(57, "TEST TEST", "another something",...) 

PICTURE(pic_id, description, other_stuff): 
(4, "A cat", "something",...) 
(2, "Another cat", "something_else",...) 
... 
(57, "finally a dog", "another something",...) 

当用户广告的新评论：

评论

(1,"What a cute cat", 2015-10-02, user24) 
(3,"That something is awesome", 2015-10-02, user87) 

链接

(1,"Picture", 4) //That comment is about the cat (Picture ID 4) 
(3, "Post",57) //That comment is about the post with ID 57