mysql : 不能有最大结果
mysql : can't have the max result
我的 mysql 请求有问题，我有这个 table :
col1
id_sec
_index
111
20
3
111
50
0
111
60
1
111
20
2
111
20
1
111
20
0
111
60
0
我想要：
col1
id_sec
_index
111
60
1
111
50
0
111
20
3
但我有：
col1
id_sec
_index
111
20
0
111
50
0
111
60
0
我的要求是：
select *
from ( select *
from test
WHERE col1 = 111
order by id_sec, _index desc
) t2
group by id_sec
感谢您的帮助！
SELECT col1, id_sec, MAX(_index) _index
FROM table
GROUP BY 1,2
ORDER BY 2 DESC;
https://dbfiddle.uk/?rdbms=mysql_8.0&fiddle=1e1155442ac7dcf3f54ba1fee5228078
我的 mysql 请求有问题，我有这个 table :
| col1 | id_sec | _index |
|---|---|---|
| 111 | 20 | 3 |
| 111 | 50 | 0 |
| 111 | 60 | 1 |
| 111 | 20 | 2 |
| 111 | 20 | 1 |
| 111 | 20 | 0 |
| 111 | 60 | 0 |
我想要：
| col1 | id_sec | _index |
|---|---|---|
| 111 | 60 | 1 |
| 111 | 50 | 0 |
| 111 | 20 | 3 |
但我有：
| col1 | id_sec | _index |
|---|---|---|
| 111 | 20 | 0 |
| 111 | 50 | 0 |
| 111 | 60 | 0 |
我的要求是：
select *
from ( select *
from test
WHERE col1 = 111
order by id_sec, _index desc
) t2
group by id_sec
感谢您的帮助！
SELECT col1, id_sec, MAX(_index) _index
FROM table
GROUP BY 1,2
ORDER BY 2 DESC;
https://dbfiddle.uk/?rdbms=mysql_8.0&fiddle=1e1155442ac7dcf3f54ba1fee5228078