Question

我有3张桌子

表新闻：

id_post | news      | id_user
3       | IT news   | 1 
4       | game news | 2

表用户：

id_user | username
   1    | bocah
   2    | gundul
   3    | ganteng

和表投票

id_vote | id_post | id_user | LIKE
10      | 3       | 2       | 1
11      | 3       | 3       | 1
12      | 3       | 1       | 1

这是我的SQL查询：

SELECT id_vote, u.id, username, SUM(v.like) AS like FROM vote v
LEFT JOIN user u ON v.id_user=u.id 
LEFT JOIN post p ON v.id_post=p.id_post 
WHERE YEARWEEK(p.time)=YEARWEEK(NOW()) 
GROUP BY u.id ORDER BY like DESC LIMIT 4

我想显示最新用户总数，例如本周新闻的位置。在我的期望用户1中，bocah将显示 3 LIKE 。问题是用户1，bocah，只收到1个LIKE。

任何答案？

Answer 1

尝试以下查询。它应该按照您的期望工作。

SELECT u.id_user, u.username, SUM(v.like) AS like
FROM USER u 
LEFT JOIN news n ON u.id_user=n.id_user 
LEFT JOIN vote v ON v.id_post=n.id_post 
WHERE YEARWEEK(v.time)=YEARWEEK(NOW()) 
GROUP BY u.id_user

Answer 2

从投票表中删除id_user列。（冲突，你在投票表中显示用户2的不同帖子。）然后像这样进行查询，我猜它会对你有帮助。

select sum(`likes`) as `Like`, user.user_id , user.id_user from vote v
LEFT JOIN news n ON v.id_post=n.id_post 
LEFT JOIN user u ON n.id_user=u.id_user 
where <your time condition>
group by v.id_post
order by `like` desc limit 4

Answer 3

试试这个：

SELECT 
  n.*,
  u.`username`,
  (SELECT SUM(`like`) FROM vote WHERE id_post = n.`id_post` ) AS likes
FROM news n
INNER JOIN `user` u ON u.`id_user` = n.`id_user`
WHERE YEARWEEK(n.time)=YEARWEEK(NOW())
ORDER BY likes DESC LIMIT 4;

从表格中我可以看到，你希望每个新闻帖的最高票数赞成吗？我假设日期时间字段在新闻表中，还是在投票完成时？

结果：

id_post |news      |id_user | username | likes

3       | IT News  |1       | gandul   |3
4       |game news |2       | bocah    |(NULL)

MySQL - 显示加入的总和

3 个答案: