评论表mySQL

Question

我想创建一个'comments'表，所以保存text，created，userId等......

但是用户可以评论很多事情。

所以我不能把一个外键放到'Post'表中，因为我还需要能够对'Picture'表进行评论，对此最好的做法是什么？

所以基本上是一个多表链接表？

Answer 1

评论表：

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

链接表

link(comment_id,comment_type, refID, )

其中comment_type将是您评论的表的名称（“图片”，“帖子”，...）。 comment_id将是用户发表的评论的ID。 refID是用户评论过的表的id（Post_id，Picture_id，...）

假设您有这些表条目：

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",...)

当用户刊登新评论时：

注释

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

链路

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