select user_id FROM sys_user_post sup INNER JOIN sys_user su on suuser_id = supuser_idwhere suppost_id=2 and sudept_id =1 1052 - Column user_id in field list is ambiguous给出上面sql错误的解决办法

在选择user_id时，应该明确指定是哪个表的user_id，可以在字段前加上表名或别名，例如：

SELECT sup.user_id FROM sys_user_post sup INNER JOIN sys_user su ON su.user_id = sup.user_id WHERE sup.post_id = 2 AND su.dept_id = 1

或者使用别名来代替完整的表名，例如：

SELECT u.user_id FROM sys_user_post sup INNER JOIN sys_user u ON u.user_id = sup.user_id WHERE sup.post_id = 2 AND u.dept_id = 1