+--------+--------+---------------------+
| dev_id | rtime  | ptime               |
+--------+--------+---------------------+
|     40 | 10.001 | 0000-00-00 00:00:00 |
|     40 | 10.001 | 2007-01-17 00:00:00 |
|     40 | 10.001 | 0000-00-00 00:00:00 |
|     40 | 10.001 | 2007-01-17 08:56:40 |
|     40 |  4.012 | 2007-01-17 08:58:07 |
|    615 |  5.245 | 2007-01-17 09:30:54 |
|    615 | 10.245 | 2007-01-17 09:34:12 |
+--------+--------+---------------------+