建设铁路时刻表答案

【问题标题】：Building railway timetable建设铁路时刻表
【发布时间】：2017-10-01 06:45:59
【问题描述】：

我希望使用 asp.net web api & sql server 数据库建立一个铁路时刻表。

以下是时间表的示例数据库设计。我使用这个查询来尝试查找时间表的算法。

我当前的问题是当我尝试源和目标[A-B] 时，它也会重新运行[B-A] 结果。我仍然没有考虑时间因素。也感谢您的宝贵建议。

预期输出：

我还有停靠点的地理位置..

   DECLARE @Souce INT  =  2 , @Destination INT = 11


DECLARE @Routes TABLE(
    ID INT,
    RouteStart VARCHAR(MAX),
    RouteStop VARCHAR(MAX)
)

DECLARE @TrainTimeTable TABLE( 
    ID              INT,
    RoutID          INT,
    Sequance        INT, -- determine the next station of the same route
    BeforeStation   INT,
    CurrentStation  INT,
    [Arr.Time]      TIME,
    [Dep.Time]      TIME
)

DECLARE @Halts TABLE(

    ID INT,
    Name    VARCHAR(MAX)
)



INSERT INTO @Routes VALUES  (1,'A','B'),
                            (2,'B', 'C'),
                            (3,'B', 'A');

INSERT INTO @Halts VALUES   (1,'A1'),
                            (2,'A2'),
                            (3,'A3'),
                            (4,'A4'),
                            (5,'A5'),
                            (6,'A6'),
                            (7,'B1'),
                            (8,'B2'),
                            (9,'B3'),
                            (10,'B4'),
                            (11,'B5'),
                            (12,'B6');

/*A To B*/
INSERT @TrainTimeTable VALUES   (1,1,1,1,1,'06:00','6:01'),
                                (2,1,2,1,2,'6:05' ,'6:06'),
                                (3,1,3,2,3,'6:10' ,'6:11'),
                                (4,1,4,3,4,'6:15' ,'6:16'),
                                (5,1,5,4,5,'6:20' ,'6:21'),
                                (6,1,6,5,6,'6:25' ,'6:25'); -- Stops here



/*B To C*/
INSERT @TrainTimeTable VALUES   (7,2,1,6,6,'6:30','6:31'),
                                (8,2,2,6,7,'6:35','6:36'),
                                (9,2,3,7,8,'6:40','6:41'),
                                (10,2,4,8,9,'6:45','6:46'),
                                (11,2,5,9,10,'6:50','6:51'),
                                (12,2,6,10,11,'7:00','7:01'),
                                (13,2,7,11,12,'7:10','7:10'); -- stops here

/*B to A*/
INSERT @TrainTimeTable VALUES   (14,3,1,6,6,'06:00','6:01'),
                                (15,3,2,6,5,'6:05' ,'6:06'),
                                (16,3,3,5,4,'6:10' ,'6:11'),
                                (17,3,4,4,3,'6:15' ,'6:16'),
                                (18,3,5,3,2,'6:20' ,'6:21'),
                                (19,3,6,2,1,'6:25' ,'6:25'); -- Stops here

SELECT  tc.*,
        hl1.Name AS 'BeforeName', 
        hl2.Name AS 'CurrentName', 
        rr.RouteStart + ' - '+rr.RouteStop AS 'Route' 
FROM @TrainTimeTable  tc
INNER JOIN @Routes rr ON rr.ID = tc.RoutID
INNER JOIN @Halts hl1 ON hl1.ID = tc.BeforeStation
INNER JOIN @Halts hl2 ON hl2.ID = tc.CurrentStation
WHERE tc.CurrentStation BETWEEN @Souce AND @Destination

【问题讨论】：

你能包括你期望的输出吗？
请期待结果。
您能解释一下您的表架构以及它与其他表的关系吗
@Xedni 问题已更新。
@Sami - 问题已更新

标签： sql .net sql-server

【解决方案1】：

给你：

SELECT  tc.*,
        hl1.Name AS 'BeforeName', 
        hl2.Name AS 'CurrentName', 
        rr.RouteStart + ' - '+rr.RouteStop AS 'Route' 
FROM @TrainTimeTable  tc
INNER JOIN @Routes rr ON rr.ID = tc.RoutID
LEFT JOIN @Halts hl1 ON hl1.ID = tc.BeforeStation
LEFT JOIN @Halts hl2 ON hl2.ID = tc.CurrentStation
WHERE tc.CurrentStation BETWEEN @Souce AND @Destination
AND tc.RoutID < 3;

结果：

+----+--------+----------+---------------+----------------+----------+----------+------------+-------------+-------+
| ID | RoutID | Sequance | BeforeStation | CurrentStation | Arr.Time | Dep.Time | BeforeName | CurrentName | Route |
+----+--------+----------+---------------+----------------+----------+----------+------------+-------------+-------+
|  2 |      1 |        2 |             1 |              2 | 06:05:00 | 06:06:00 | A1         | A2          | A - B |
|  3 |      1 |        3 |             2 |              3 | 06:10:00 | 06:11:00 | A2         | A3          | A - B |
|  4 |      1 |        4 |             3 |              4 | 06:15:00 | 06:16:00 | A3         | A4          | A - B |
|  5 |      1 |        5 |             4 |              5 | 06:20:00 | 06:21:00 | A4         | A5          | A - B |
|  6 |      1 |        6 |             5 |              6 | 06:25:00 | 06:25:00 | A5         | A6          | A - B |
|  7 |      2 |        1 |             6 |              6 | 06:30:00 | 06:31:00 | A6         | A6          | B - C |
|  8 |      2 |        2 |             6 |              7 | 06:35:00 | 06:36:00 | A6         | B1          | B - C |
|  9 |      2 |        3 |             7 |              8 | 06:40:00 | 06:41:00 | B1         | B2          | B - C |
| 10 |      2 |        4 |             8 |              9 | 06:45:00 | 06:46:00 | B2         | B3          | B - C |
| 11 |      2 |        5 |             9 |             10 | 06:50:00 | 06:51:00 | B3         | B4          | B - C |
| 12 |      2 |        6 |            10 |             11 | 07:00:00 | 07:01:00 | B4         | B5          | B - C |
+----+--------+----------+---------------+----------------+----------+----------+------------+-------------+-------+

【讨论】：

感谢您的回答。但是我们如何确定我何时从一个简单的 ui 中选择源和目标而不包括路由 3。例如，想想是否有另一个路由器 C

【解决方案2】：

您可以将此谓词添加到 where 子句的末尾。

AND tc.ID <= (SELECT TOP 1 ID FROM @TrainTimeTable WHERE CurrentStation =  @Destination ORDER BY ID)

【讨论】：

根据您的样本数据，您应该在目标点剪切序列。我更新了脚本。