left join 多张表答案

【问题标题】：left join more than one tableleft join 多张表
【发布时间】：2019-12-30 03:27:26
【问题描述】：

基本上我想离开加入 3 个表我已经加入了下面的 2 个表

SELECT  * 
FROM    Shop_id i
        LEFT JOIN Shopper s 
           ON i.shopper_id = s.uid
WHERE   i.shopper_comp > 0 AND 
        i.editor_comp = 0
ORDER BY i.sid

我已经成功加入 Shop_id i 和 Shopper s 我想将 Clients c 添加到我想的组合中-

SELECT  * 
FROM    Shop_id i
        LEFT JOIN Shopper s, Clients c 
           ON i.shopper_id = s.uid AND i.cid = c.CID
WHERE   i.shopper_comp > 0 AND 
        i.editor_comp = 0
ORDER BY i.sid

我错了 - 请帮忙

【问题讨论】：

标签： mysql sql

【解决方案1】：

您需要为表clients 显式指定关键字LEFT JOIN。

SELECT * 
FROM   Shop_id i
       LEFT JOIN Shopper s
          ON i.shopper_id = s.uid 
       LEFT JOIN Clients c 
          ON i.cid = c.CID
WHERE  i.shopper_comp > 0 AND 
       i.editor_comp = 0
ORDER BY i.sid

【讨论】：

【解决方案2】：

你可以这样试试吗？

SELECT * FROM Shop_id i
LEFT JOIN Shopper s ON i.shopper_id = s.uid
LEFT JOIN Clients c ON  i.cid = c.CID
WHERE i.shopper_comp >0 AND i.editor_comp =0
ORDER BY i.sid

【讨论】：