作业：
1.创建用户user1、user2和user3，user1具有CREATEROLE权限，user2具有CREATEDB权限，要求使用两种不同的方法设置密码
omm=# create user user1 createrole password 'test_1234';
NOTICE: The encrypted password contains MD5 ciphertext, which is not secure.
CREATE ROLE
omm=# create user user2 createdb password 'test_1234';
NOTICE: The encrypted password contains MD5 ciphertext, which is not secure.
CREATE ROLE
omm=# create user user3 identified by 'test_1234';
NOTICE: The encrypted password contains MD5 ciphertext, which is not secure.
CREATE ROLE
omm=# \du
List of roles
Role name | Attributes
| Member of
-----------+------------------------------------------------------------------------------------------------------------------
+-----------
gaussdb | Sysadmin
| {}
omm | Sysadmin, Create role, Create DB, Replication, Administer audit, Monitoradmin, Operatoradmin, Policyadmin, UseFT
| {}
user1 | Create role
| {}
user2 | Create DB
| {}
user3 |
| {}
2.修改用户user1的密码
omm=# alter user user1 identified by 'TEST_1234';
NOTICE: The encrypted password contains MD5 ciphertext, which is not secure.
ALTER ROLE
omm=# alter user user1 password 'TTTT_1234';
NOTICE: The encrypted password contains MD5 ciphertext, which is not secure.
ALTER ROLE
3.重命名用户user2
omm=# alter user user2 rename to user22;
NOTICE: MD5 password cleared because of role rename
ALTER ROLE
omm=# \du
List of roles
Role name | Attributes
| Member of
-----------+------------------------------------------------------------------------------------------------------------------
+-----------
gaussdb | Sysadmin
| {}
omm | Sysadmin, Create role, Create DB, Replication, Administer audit, Monitoradmin, Operatoradmin, Policyadmin, UseFT
| {}
user1 | Create role
| {}
user3 |
| {}
user22 | Create DB
| {}
4.将用户user1的权限授权给用户user3，再回收用户user3的权限
omm=# grant user1 to user3;
GRANT ROLE
omm=# \du
List of roles
Role name | Attributes
| Member of
-----------+------------------------------------------------------------------------------------------------------------------
+-----------
gaussdb | Sysadmin
| {}
omm | Sysadmin, Create role, Create DB, Replication, Administer audit, Monitoradmin, Operatoradmin, Policyadmin, UseFT
| {}
user1 | Create role
| {}
user22 | Create DB
| {}
user3 |
| {user1}
omm=# revoke user1 from user3;
REVOKE ROLE
omm=# \du
List of roles
Role name | Attributes
| Member of
-----------+------------------------------------------------------------------------------------------------------------------
+-----------
gaussdb | Sysadmin
| {}
omm | Sysadmin, Create role, Create DB, Replication, Administer audit, Monitoradmin, Operatoradmin, Policyadmin, UseFT
| {}
user1 | Create role
| {}
user22 | Create DB
| {}
user3 |
| {}
5.删除所有创建用户
omm=# drop user user1;
DROP ROLE
omm=# drop user user22;
DROP ROLE
omm=# drop user user3;
DROP ROLE
omm=# \du
List of roles
Role name | Attributes
| Member of
-----------+------------------------------------------------------------------------------------------------------------------
+-----------
gaussdb | Sysadmin
| {}
omm | Sysadmin, Create role, Create DB, Replication, Administer audit, Monitoradmin, Operatoradmin, Policyadmin, UseFT
| {}
过程中使用\du或\du+查看用户信息
