从三个表获取数据的mysql加入

Question

我在我的数据库中的三个表

1.Users（ID，用户名）

2.Stories（ID，USER_ID，内容）这里是user_id关键forigen指Users表id

3.Comments（ID，USER_ID，story_id，评论）这里user_id是forigen键指Users表id和story_id是forigen键指Stories表id

我需要从Stories表中获取的故事名单与上storie笔者

下面的那个帖子和用户名评论总数是我对于

SELECT stories.id,stories.content,COUNT(stories.id) as totalcomment 
FROM stories 
JOIN comments 
ON stories.id=comments.story_id GROUP BY stories.id 

我会得到总查询

Answer 1

的每个岗位的评论，但不能取storie作者（从用户表即用户名）的用户名试试这个：

SELECT stories.id,stories.content,COUNT(stories.id) as totalcomment, Users.username 
FROM stories, Users, comments 
WHERE stories.id=comments.story_id 
AND stories.user_id = Users.id 
GROUP BY stories.id 

或者与加盟：

SELECT stories.id,stories.content,COUNT(stories.id) as totalcomment, Users.username 
FROM stories 
JOIN comments ON stories.id=comments.story_id 
JOIN users ON stories.user_id = Users.id 
GROUP BY stories.id 

希望这个作品。

Answer 2

SELECT s.id,s.content,COUNT(c.story_id) as totalcomment, u.username 
FROM stories s LEFT JOIN comments c ON (s.id=c.story_id) 
LEFT JOIN users u ON (s.user_id = u.id) 
GROUP BY s.id