Question

如何基于两列对行进行排序，您首先按column1进行排序，但是如果行具有相同的值（并列），则按column2对行进行排序？

id | likes | date
---+-------+-----
0      0     203
1      8     100
2      4     24
3      1     340
4      4     262
5      4     82

因此对于上面的示例表，首先基于likes进行排序，然后对于具有4的3行，基于date DESC进行排序？

注意：date仅具有任意的unix时间戳记值

编辑： 这是我正在使用的实际查询：

SELECT * FROM (SELECT posts.id, posts.topic_id, topics.name, 
posts.author_id, users.username, users.profile_pic, posts.date_posted, 
posts.body, posts.coordinates, (SELECT COUNT(*) FROM post_likes WHERE 
post_likes.post_id = posts.id) AS num_likes, 
ROW_NUMBER () OVER (ORDER BY (SELECT COUNT(*) FROM post_likes WHERE 
post_likes.post_id = posts.id) DESC, posts.date_posted DESC) AS RowNum 
FROM posts INNER JOIN users ON posts.author_id = users.id INNER JOIN 
topics ON posts.topic_id = topics.id WHERE author_id = 'foo') AS 
RowConstrainedResult WHERE RowNum > 0 AND RowNum <= 20 ORDER BY RowNum

Answer 1

您将命令其为

<
select 
 from table
>
order by likes desc
         , date desc

Answer 2

我认为这是您所需要的：

Select * from table
ORDER BY likes, date DESC;

这将产生如下输出：

id  likes   date
0   0       203
3   1       240
4   4       262
5   4       82
2   4       24
1   8       100

检查DEMO here。

PostgreSQL：如果有关系，则根据另一列进行排序？

2 个答案: