mysql - 重命名从 SQL 连接查询返回的值

Question

假设我们有以下查询

SELECT b.user_name, c.user_name, msg 
FROM user_messages a
JOIN users b ON b.user_id = a.user_from 
JOIN users c ON c.user_id = a.user_to 
WHERE a.user_from = 'ds4EpcrmUt' 
OR a.user_to = 'ds4EpcrmUt'

当从 NodeJS 查询时，我只会收到一个 user_names，因为两个返回值具有相同的名称。

有没有办法重命名它们的返回值，如下所示？

b.user_name = user_from
c.user_name = user_to

Answer 1

试试下面-

SELECT b.user_name as user_from, c.user_name as user_to, msg 
FROM user_messages a
JOIN users b ON b.user_id = a.user_from 
JOIN users c ON c.user_id = a.user_to 
WHERE a.user_from = 'ds4EpcrmUt' 
OR a.user_to = 'ds4EpcrmUt'