mysql - #1066 - 不是唯一的表/别名 : 'tb_X'

Question

我在尝试连接 3 个表时遇到问题。

以下是我使用的 mysql 语法:

SELECT
FROM carecell
LEFT JOIN staff ON cc.id_pks = staff.id_emp
LEFT JOIN staff ON cc.id_wpks = staff.id_emp
INNER JOIN member ON member.id_member = staff.id_member

请帮助我..我应该怎么做才能修复语法？

Answer 1

SQL 引擎无法区分from 子句中的两个staff 表。你需要给他们不同的名字。像这样:

FROM carecell cc LEFT JOIN
     staff s1
     ON cc.id_pks = s1.id_emp LEFT JOIN
     staff s2
     ON cc.id_wpks = s2 .id_emp INNER JOIN
     member m
     ON m.id_member = s2.id_member