CREATE ROLE
CREATE ROLE 语句是基于角色的访问控制 (RBAC) 操作的一部分，用于创建新角色并将新角色分配给用户。
语法图
- CreateRoleStmt
- IfNotExists
- RoleSpec
CreateRoleStmt ::=
'CREATE' 'ROLE' IfNotExists RoleSpec (',' RoleSpec)*
IfNotExists ::=
('IF' 'NOT' 'EXISTS')?
RoleSpec ::=
Rolename
示例
以 root 用户连接 TiDB：
mysql -h 127.0.0.1 -P 4000 -u root
创建新角色 analyticsteam 和新用户 jennifer：
CREATE ROLE analyticsteam;
Query OK, 0 rows affected (0.02 sec)
GRANT SELECT ON test.* TO analyticsteam;
Query OK, 0 rows affected (0.02 sec)
CREATE USER jennifer;
Query OK, 0 rows affected (0.01 sec)
GRANT analyticsteam TO jennifer;
Query OK, 0 rows affected (0.01 sec)
以 jennifer 用户连接 TiDB：
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：
SHOW GRANTS;
+---------------------------------------------+
| Grants for User |
+---------------------------------------------+
| GRANT USAGE ON *.* TO 'jennifer'@'%' |
| GRANT 'analyticsteam'@'%' TO 'jennifer'@'%' |
+---------------------------------------------+
2 rows in set (0.00 sec)
SHOW TABLES in test;
ERROR 1044 (42000): Access denied for user 'jennifer'@'%' to database 'test'
SET ROLE analyticsteam;
Query OK, 0 rows affected (0.00 sec)
SHOW GRANTS;
+---------------------------------------------+
| Grants for User |
+---------------------------------------------+
| GRANT USAGE ON *.* TO 'jennifer'@'%' |
| GRANT SELECT ON test.* TO 'jennifer'@'%' |
| GRANT 'analyticsteam'@'%' TO 'jennifer'@'%' |
+---------------------------------------------+
3 rows in set (0.00 sec)
SHOW TABLES IN test;
+----------------+
| Tables_in_test |
+----------------+
| t1 |
+----------------+
1 row in set (0.00 sec)
以 root 用户连接 TiDB：
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：
SET DEFAULT ROLE analyticsteam TO jennifer;
Query OK, 0 rows affected (0.02 sec)
以 jennifer 用户连接 TiDB：
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：
SHOW GRANTS;
+---------------------------------------------+
| Grants for User |
+---------------------------------------------+
| GRANT USAGE ON *.* TO 'jennifer'@'%' |
| GRANT SELECT ON test.* TO 'jennifer'@'%' |
| GRANT 'analyticsteam'@'%' TO 'jennifer'@'%' |
+---------------------------------------------+
3 rows in set (0.00 sec)
SHOW TABLES IN test;
+----------------+
| Tables_in_test |
+----------------+
| t1 |
+----------------+
1 row in set (0.00 sec)
MySQL 兼容性
CREATE 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。