hibernate 如何进行连接表(中间表)查询与更新
小弟不才,特来请教!
现有三张表,user\role\user_role(中间表)
+---------+-------------+----------+--------+----------+
| user_id | description | password | status | username |
+---------+-------------+----------+--------+----------+
| 1 | | admin | 1 | admin |
| 2 | | user | 1 | user |
| 3 | | user | 1 | lml |
+---------+-------------+----------+--------+----------+
3 rows in set (0.08 sec)
mysql> select * from role;
+---------+----------------+------------+
| role_id | authentication | name |
+---------+----------------+------------+
| 1 | | ROLE_ADMIN |
| 2 | | ROLE_USER |
+---------+----------------+------------+
2 rows in set (0.06 sec)
mysql> select * from user_role;
+---------+---------+
| user_id | role_id |
+---------+---------+
| 1 | 1 |
| 1 | 2 |
| 2 | 2 |
+---------+---------+
这三张表是通过hibernate自动形成的,映射关系我是放在user表中,采用注解@many2many形式,
现在我有两个想法,1、是在添加新用户时,就自动更新中间表(user_role)
2、是想通过查询user中的id,来查询user_role中的role_id
谢谢!!