我一直在尝试为公共交通系统编写查询,当我输入起点和终点站号时,该系统将输出路线列表。
这是我的 MySQL 表:
mysql> desc route_timings;
+----------------+---------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+----------------+---------+------+-----+---------+----------------+
| ID | int(11) | NO | PRI | NULL | auto_increment |
| route_number | int(11) | NO | | NULL | |
| stop_number | int(11) | NO | | NULL | |
| arrival_time | time | YES | | NULL | |
| departure_time | time | YES | | NULL | |
+----------------+---------+------+-----+---------+----------------+
5 rows in set (0.00 sec)
以下是示例值:
mysql> select * from route_timings;
+----+--------------+-------------+--------------+----------------+
| ID | route_number | stop_number | arrival_time | departure_time |
+----+--------------+-------------+--------------+----------------+
| 1 | 54 | 1 | 10:00:00 | 10:05:00 |
| 2 | 54 | 2 | 11:00:00 | 11:05:00 |
| 3 | 54 | 3 | 12:00:00 | 12:05:00 |
| 4 | 55 | 3 | 13:00:00 | 13:05:00 |
| 5 | 55 | 4 | 14:00:00 | 14:05:00 |
| 6 | 55 | 5 | 15:00:00 | 15:05:00 |
| 7 | 60 | 3 | 10:00:00 | 10:05:00 |
| 8 | 60 | 2 | 11:00:00 | 11:05:00 |
| 9 | 60 | 1 | 12:00:00 | 12:05:00 |
+----+--------------+-------------+--------------+----------------+
9 rows in set (0.01 sec)
我的问题是:如果我想列出包含 stop_number 1 和 stop_number 3 的 route_number,我会写一个类似这样的查询:
SELECT DISTINCT `route_number` FROM `route_timings` WHERE `route_number` IN (
SELECT `route_number` FROM `route_timings` WHERE `stop_number`=1
) AND `route_number` IN (
SELECT `route_number` FROM `route_timings` WHERE `stop_number`=3
);
但是,上述查询将仅返回包含两个站点的 route_numbers,而不是源站点 (1) 在目标站点 (3) 之前到达的路线。
该查询将返回以下内容:
+--------------+
| route_number |
+--------------+
| 54 |
| 60 |
+--------------+
route_number 60 不是从 1 开始到 3,而是从 3 开始到 1。有人可以帮我将该位添加到查询中,以便查询仅输出 stop_number 1 的到达时间较少的 route_numbers比 stop_number 3 的到达时间。
提前致谢。-谢恩