2011-10-01 71 views
1

例如說我有如下表(正式成員之間的連接)在SQL結合共同的價值觀

connectionA ConnectionB 
    887    225 
    129    887 
    225    887 
    887    562 
    562    887 

我怎麼能夠使用SQL來找到所有地方都A連接到B行反之亦然。查詢將返回(不允許重複):

connectionA ConnectionB 
    887    225 
    887    562 

回答

3
SELECT T1.connectionA, T1.connectionB 
FROM yourtable T1 
JOIN yourtable T2 
ON T1.connectionA = T2.connectionB 
AND T2.connectionA = T1.connectionB 
WHERE T1.connectionA > T1.connectionB