mysql - MySQL - 左和自联接在单个查询中

正如标题所述，我试图从表B中继续加入信息，但随后也在表A中显示匹配信息，这些信息在表B中没有关联。下面是我的查询，但它目前只返回内部加入。

SELECT 
    concat(u.firstname, ' ', u.lastname) AS clientName,
    u.email AS clientEmail, 
    u.created_at AS signedUp,
    u.refferedby AS referredBy,
    concat(t.firstname, ' ', t.lastname) AS trainerWho,
    t.email AS trainerWhoEmail,
    concat(usr.firstname, ' ', usr.lastname) AS clientWho,
    usr.email as clientWhoEmail
FROM users u
LEFT JOIN trainers t ON u.externalid = t.hashId
    INNER JOIN users usr ON u.externalid = usr.hashId
WHERE u.refferedby IS NOT NULL
    AND DATE(u.created_at) >= CURDATE() -7
    ORDER BY(u.created_at);

MySQL - 左和自联接在单个查询中

0 个答案: