SQL查询2个不同的表

Question

我有桌子：

1. 旅行：Trip_Num，Trip_Type等
2. 用户的旅程历史：用户名，Trip_Num等

我在php中做一个项目，需要为特定用户（通过他的用户名）进行SQL查询 - 需要知道用户旅行历史表中Trip_Num的Trip_Type。

附上我的表格：

行程



用户的旅行历史



更新： 我需要对Trip_type中的每个值进行计数。我的意思是我想看到＆＃34;步行＆＃34; - 4次出现，＆＃34;自行车＆＃34; - 3次出现，这很好吗？.......................................... .................................选择Trips_History。*，Trips.Trip_Type，COUNT（Trip_Type）AS Trip_Type_occurrence FROM Trips历史INNER JOIN Trips on Trips_History.Trip_Num = Trips.Trip_Num GROUP BY Trip_Type ORDER BY Trip_Type_occurrence DESC -

Answer 1

一个简单的JOIN会：

SELECT
    th.*,
    t.Trip_Type
FROM Trip_History AS th
INNER JOIN Trips AS t
    ON t.Trip_Num = th.Trip_Num

Answer 2

试试这个：

 select Trips_History.*,COUNT(Trips.Trip_Type) AS Trip_Type_occurrence FROM Trips_History INNER JOIN Trips on Trips_History.Trip_Num = Trips.Trip_Num  GROUP BY Trip_Type ORDER BY Trip_Type_occurrence DESC

Answer 3

试试这个

select t2.traveller_username,t1.Trip_Type from 
trips as t1 inner join trips_history as t2 on t1.Trip_num=t2.trip_num

Answer 4

尝试，

SELECT t.Trip_Type, u.Trip_Num from trips at t 
JOIN user_trips_history ON u.Trip_Num = t.Trip_Num 
WHERE u.Traveller_Username = 'username';

Answer 5

尝试做：

SELECT t.Trip_Type, u.Trip_Num FROM trips as t 
JOIN user_trips_history as u ON t.Trip_Num=u.Trip_Num 
WHERE u.Traveller_Username = 'USERNAME';

Answer 6

你可以试试这个 -

SELECT users_trip_history.trip_num, trips.trip_type, COUNT(trips.trip_type) AS trip_occurences
FROM users_trip_history
INNER JOIN trips
ON users_trip_history.trip_num = trips.trip_num 
WHERE users_trip_history.traveler_username = "name"
GRUOP BY trip_num;