有條件的左聯接中的查詢問題

Question

我有這個查詢，可以幫助我獲取當前用戶的積分，現在，我在設置條件時遇到問題...

$query4 =  'SELECT u.*, SUM(c.ts) AS total_sum1, SUM(r.bv) AS total_sum 
FROM users u 
LEFT JOIN 
 (SELECT user_id ,SUM(points) AS ts FROM coupon GROUP BY user_id) c 
 ON u.user_id=c.user_id AND u.user_id="'.$_SESSION['user_name'].'"
LEFT JOIN 
 (SELECT user_id ,SUM(basket_value) AS bv FROM retailer GROUP BY user_id) r 
ON u.user_id=r.user_id 
GROUP BY u.user_id';

我的問題是AND u.user_id="'.$_SESSION['user_name'].'"

我需要為該特定用戶找到要點。.我做錯了嗎？ 我的意思是，我知道我是，但是呢？ 謝謝

Answer 1

這樣寫你的查詢

$query4 =  'SELECT u.*, SUM(c.ts) AS total_sum1, SUM(r.bv) AS total_sum 
FROM users u 
LEFT JOIN 
 (SELECT user_id ,SUM(points) AS ts FROM coupon GROUP BY user_id) c 
 ON u.user_id=c.user_id 
LEFT JOIN 
 (SELECT user_id ,SUM(basket_value) AS bv FROM retailer GROUP BY user_id) r 
ON u.user_id=r.user_id 
where u.user_id="'.$_SESSION['user_name'].'"
GROUP BY u.user_id';