加入两个表的多个外键

Question

表Trips

TripId_PK 
StartLocationId_FK 
EndLocationId_FK 

表Locations

LocationId_PK 
Name 

我如何加入两个表的两倍，这样我可以得到这样一个数据集：

TripId_PK 
StartLocationName 
EndLocationName 

在此先感谢。

Answer 1

SELECT t.TripId_PK, ls.name StartLocationName, le.name EndLocationName 
FROM trips t 
JOIN locations ls 
ON  ls.LocationId_PK = t.StartLocationId_FK 
JOIN locations le 
ON  le.LocationId_PK = t.EndLocationId_FK 

Answer 2

你可以试试这个

SELECT t.TripId_PK, ls.StartLocationName, le.EndLocationName 
FROM Trips t 
JOIN Locations ls ON t.StartLocationId_FK = ls.LocationId_PK 
JOIN Locations le ON t.EndLocationId_FK = le.LocationId_PK