加入用戶和追隨者表

Question

我有用戶表，並按照如下表表 我有用戶ID - 和 - 跟隨ID

我必須做出列表，我必須考慮的用戶的電子郵件ID和隨

我怎麼能加入這兩個表

select f.USER_ID ,a.user_firstname, a.user_email ,f.Follow_Id 
from bb_follow f, bb_user a 
where a.user_id = f.User_Id and f.Active_Status=1 order by f.User_Id asc 

（現在我想跟隨的信息 - 我如何添加） -

Answer 1

這裏有一個整體的你，語法iswro NG，你需要

SELECT *加入，從bb_follow樓 JOIN bb_user一個 ON f.User_id = a.user_id WHERE f.Active_Status = '1'

試一下，然後加入您的具體值

Answer 2

試試這個：

SELECT f.USER_ID, a.user_firstname userName, a.user_email userEmail, 
     f.Follow_Id, b.user_firstname followerName, b.user_email followerEmail 
FROM bb_follow f 
LEFT JOIN bb_user a ON a.user_id = f.User_Id 
LEFT JOIN bb_user b ON b.user_id = f.Follow_Id 
WHERE f.Active_Status=1 
ORDER BY f.User_Id ASC; 

Answer 3

加入bb_user表兩次，別名爲一個（用戶）和b（用於跟隨者）。

select f.USER_ID, a.user_firstname, a.user_email, 
     f.FOLLOW_ID, b.user_firstname as follower_firstname, b.user_email as follower_email 
from bb_follow f, bb_user a, bb_user b 
where a.user_id = f.User_Id 
and b.user_id = f.Follow_Id 
and f.Active_Status=1 

或ANSI連接：

select f.USER_ID, a.user_firstname, a.user_email, 
     f.FOLLOW_ID, b.user_firstname as follower_firstname, b.user_email as follower_email 
from bb_follow f 
     join bb_user a on a.user_id = f.User_Id 
     join bb_user b on b.user_id = f.Follow_Id 
where f.Active_Status=1