MySQL分组排序取前N条记录以及生成自动数字序列--groupby后limit外加rownumber(二)
b.machine=a.machine and b.time=a.time where b.rownum<5;
Query OK, 0 rows affected (0.00 sec)
Query OK, 0 rows affected (0.00 sec)
+------------+---------------+--------+------------+-----------+--------+
| time | machine | module | total_flow | deny_flow | rownum |
+------------+---------------+--------+------------+-----------+--------+
| 1409640360 | 10.201.20.181 | all | 53937 | 6058 | 1 |
| 1409640300 | 10.201.20.181 | all | 52588 | 5701 | 2 |
| 1409640240 | 10.201.20.181 | all | 54254 | 5608 | 3 |
| 1409640180 | 10.201.20.181 | all | 54684 | 5811 | 4 |
| 1409640360 | 10.201.20.97 | all | 50679 | 5307 | 1 |
| 1409640300 | 10.201.20.97 | all | 50472 | 5239 | 2 |
| 1409640240 | 10.201.20.97 | all | 51586 | 5509 | 3 |
| 1409640180 | 10.201.20.97 | all | 50794 | 5378 | 4 |
| 1409640360 | 10.201.20.98 | all | 84747 | 5652 | 1 |
| 1409640300 | 10.201.20.98 | all | 84506 | 5696 | 2 |
| 1409640240 | 10.201.20.98 | all | 84982 | 5513 | 3 |
| 1409640180 | 10.201.20.98 | all | 83997 | 5623 | 4 |
+------------+---------------+--------+------------+-----------+--------+