在SELECT語句中從相同表中獲取兩個項目

Question

我需要提取兩個團隊的名稱，從同一個表中抽取兩個團隊的SQL SELECT語句。例如低於

SELECT sport_activity_id, (team A), (team B), date, time 
FROM sportactivity, teams 
WHERE competition_id_fk = 2 

對於（團隊A）和（B隊），我有一個TEAM_ID，這是一個FK表「團隊」

是否有可能得到這些表由以下結果SQL？ 1，巴塞羅那，阿森納，01/01/2000，20:00

兩個表如下：

表sportactivity

sport_activity_id, home_team_fk, away_team_fk, competition_id_fk, date, time 

（元組的例子） - > 1， 33，41，如圖5所示，2010-04-14，5時40分○○秒

表隊

team_id, team_name 

（元組爲例） - > 1，阿爾及利亞

Answer 1

是的，你只需要與團隊加盟兩次：

SELECT sport_activity_id, T1.team_name, T2.team_name, date, time 
FROM sportactivity 
JOIN teams T1 ON home_team_fk = T1.team_id 
JOIN teams T2 ON away_team_fk = T2.team_id 
WHERE competition_id_fk = 2 

Answer 2

SELECT sport_activity_id, teamA.team_Name, teamB.team_Name, date, time 
FROM sportactivity 
INNER JOIN teams teamA ON sportactivity.home_team_fk = teamA.team_ID 
INNER JOIN teams teamB ON sportactivity.away_team_fk = teamB.team_ID 
WHERE competition_id_fk = 2