Question

从下面的相册表中，我需要提取至少3个musician_ids匹配的album_ids，例如：预期的结果是 100 和 102 ，因为它们都包含musician_ids 2,3和4。

id    album_id    musician_id
1     100         1
2     100         2
3     100         3
4     100         4
5     101         3
6     101         4
7     101         5
8     101         6
9     102         2
10    102         3
11    102         4
12    102         7
13    103         1
14    103         2
15    103         8
16    103         9

使用MySQL Workbench。感谢所有的帮助！感谢。

Answer 1

试试这个

SELECT 
  `album_id`, COUNT(`album_id`) AS `count` 
FROM 
   albums 
GROUP BY 
   `album_id` 
HAVING 
   `count` >= 3

Answer 2

这是一套内置问题。这是一个典型的解决方案：

select album_id
from albums
where musician_id in (2, 3, 4)
group by album_id
having count(distinct musician_id) = 3;

编辑：

你修改过的问题似乎与原文有很大不同，但我可以看出歧义在哪里。

答案是：

select a1.album_id, a2.album_id, count(*) as nummatches,
       group_concat(a1.musician_id) as musicians
from albums a1 join
     albums a2
     on a1.musician_id = a2.musician_id and a1.album_id < a2.album_id
group by a1.album_id, a2.album_id
having count(*) >= 3;

MySQL：查找多个重复记录

2 个答案: