我正在编写此SQL查询,以检测最近登录系统的用户。截至目前我拥有的查询:
SELECT * FROM (
SELECT * FROM events WHERE eventName = 'Login' ORDER BY eventID DESC
) AS SUBQUERY
GROUP BY personID;
这是我要从中读取的原始表:
+---------+----------+-----------+--------------+----------------------------+
| eventID | personID | eventName | eventContent | timeStamp |
+---------+----------+-----------+--------------+----------------------------+
| 1 | 2 | Login | Login | On: 26/12/2019 at 16:53:34 |
| 2 | 2 | Click | Button | On: 26/12/2019 at 16:53:42 |
| 3 | 1 | Login | Login | On: 26/12/2019 at 16:53:43 |
| 4 | 1 | Login | Login | On: 26/12/2019 at 16:59:22 |
| 5 | 0 | Login | Login | On: 26/12/2019 at 17:4:34 |
| 6 | 1 | Login | Login | On: 26/12/2019 at 17:5:6 |
+---------+----------+-----------+--------------+----------------------------+
我期望的输出:
ID Login Time
1 On: 26/12/2019 at 17:5:6
0 On: 26/12/2019 at 17:4:34
2 On: 26/12/2019 at 16:53:34
输出SQL给我:
ID Login Time
0 On: 26/12/2019 at 17:4:34
1 On: 26/12/2019 at 16:53:43
2 On: 26/12/2019 at 16:53:34