SET DEFAULT ROLE

SET DEFAULT ROLE 语句默认设置将特定角色应用于用户。因此，用户不必执行 SET ROLE <rolename> 或 SET ROLE ALL 语句，也可以自动具有与角色相关联的权限。

语法图

SetDefaultRoleStmt:

SetDefaultRoleStmt

SetDefaultRoleOpt:

SetDefaultRoleOpt

RolenameList:

RolenameList

UsernameList:

UsernameList

示例

以 root 用户连接 TiDB：

  1. mysql -h 127.0.0.1 -P 4000 -u root

创建新角色 analyticsteam 和新用户 jennifer：

  1. CREATE ROLE analyticsteam;
  2. Query OK, 0 rows affected (0.02 sec)
  4. GRANT SELECT ON test.* TO analyticsteam;
  5. Query OK, 0 rows affected (0.02 sec)
  7. CREATE USER jennifer;
  8. Query OK, 0 rows affected (0.01 sec)
  10. GRANT analyticsteam TO jennifer;
  11. Query OK, 0 rows affected (0.01 sec)

以 jennifer 用户连接 TiDB：

  1. mysql -h 127.0.0.1 -P 4000 -u jennifer

需要注意的是，默认情况下，用户 jennifer 需要执行 SET ROLE analyticsteam 语句才能使用与 analyticsteam 角色相关联的权限：

  1. SHOW GRANTS;
  2. +---------------------------------------------+
  3. | Grants for User                             |
  4. +---------------------------------------------+
  5. | GRANT USAGE ON *.* TO 'jennifer'@'%'        |
  6. | GRANT 'analyticsteam'@'%' TO 'jennifer'@'%' |
  7. +---------------------------------------------+
  8. 2 rows in set (0.00 sec)
  10. SHOW TABLES in test;
  11. ERROR 1044 (42000): Access denied for user 'jennifer'@'%' to database 'test'
  12. SET ROLE analyticsteam;
  13. Query OK, 0 rows affected (0.00 sec)
  15. SHOW GRANTS;
  16. +---------------------------------------------+
  17. | Grants for User                             |
  18. +---------------------------------------------+
  19. | GRANT USAGE ON *.* TO 'jennifer'@'%'        |
  20. | GRANT Select ON test.* TO 'jennifer'@'%'    |
  21. | GRANT 'analyticsteam'@'%' TO 'jennifer'@'%' |
  22. +---------------------------------------------+
  23. 3 rows in set (0.00 sec)
  25. SHOW TABLES IN test;
  26. +----------------+
  27. | Tables_in_test |
  28. +----------------+
  29. | t1             |
  30. +----------------+
  31. 1 row in set (0.00 sec)

以 root 用户连接 TiDB：

  1. mysql -h 127.0.0.1 -P 4000 -u root

执行 SET DEFAULT ROLE 语句将用户 jennifer 与 analyticsteam 角色相关联：

  1. SET DEFAULT ROLE analyticsteam TO jennifer;
  2. Query OK, 0 rows affected (0.02 sec)

以 jennifer 用户连接 TiDB：

  1. mysql -h 127.0.0.1 -P 4000 -u jennifer

此时 jennifer 用户无需执行 SET ROLE 语句就能拥有 analyticsteam 角色相关联的权限：

  1. SHOW GRANTS;
  2. +---------------------------------------------+
  3. | Grants for User                             |
  4. +---------------------------------------------+
  5. | GRANT USAGE ON *.* TO 'jennifer'@'%'        |
  6. | GRANT Select ON test.* TO 'jennifer'@'%'    |
  7. | GRANT 'analyticsteam'@'%' TO 'jennifer'@'%' |
  8. +---------------------------------------------+
  9. 3 rows in set (0.00 sec)
  11. SHOW TABLES IN test;
  12. +----------------+
  13. | Tables_in_test |
  14. +----------------+
  15. | t1             |
  16. +----------------+
  17. 1 row in set (0.00 sec)

SET DEFAULT ROLE 语句不会自动将相关角色授予 (GRANT) 用户。若尝试为 jennifer 尚未被授予的角色执行 SET DEFAULT ROLE 语句会导致以下错误：

  1. SET DEFAULT ROLE analyticsteam TO jennifer;
  2. ERROR 3530 (HY000): `analyticsteam`@`%` is is not granted to jennifer@%

MySQL 兼容性

SET DEFAULT ROLE 语句与 MySQL 8.0 的角色功能完全兼容。如发现任何兼容性差异，请在 GitHub 上提交 issue。

另请参阅