列字段加入在MySQL查詢

Question

我有兩個表象下面這樣：

表1：

teamid teamname 
1  AAA 
2  BBB 
3  CCC 

表2：

id team1 team2 
1 1  2 
2 2  3   
3 1  3 

表2包含兩個字段TEAM1和team2參考表1 teamid。

預期結果：

id team1 team2 
1 AAA  BBB 
2 BBB  CCC 
3 AAA  CCC 

Answer 1

你需要加入table1 2倍

select 
t2.id, 
t1.teamname as team1, 
t11.teamname as team2 
from table2 t2 
join table1 t1 on t1.teamid = t2.team1 
join table1 t11 on t11.teamid = t2.team2