openGauss每日一练第5天｜openGauss创建用户、修改用户属性、更改用户权限和删除用户

坚持学习openGauss数据库，坚持每天打卡。第五天学习openGauss创建用户、修改用户属性、更改用户权限和删除用户。

连接openGauss

root@modb:~# su - omm
omm@modb:~$ gsql -r
gsql ((openGauss 2.0.0 build 78689da9) compiled at 2021-03-31 21:03:52 commit 0 last mr  )
Non-SSL connection (SSL connection is recommended when requiring high-security)
Type "help" for help.
omm=#

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 'abcd@123';
NOTICE:  The encrypted password contains MD5 ciphertext, which is not secure.
CREATE ROLE
omm=# create user user2 createdb identified by 'abcd@456';
NOTICE:  The encrypted password contains MD5 ciphertext, which is not secure.
CREATE ROLE
omm=# create user user3 identified by 'abcd@789';
NOTICE:  The encrypted password contains MD5 ciphertext, which is not secure.
CREATE ROLE

2.修改用户user1的密码

omm=# alter user user1 identified by 'abcd@321' replace 'abcd@123';
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 user20;
NOTICE:  MD5 password cleared because of role rename
ALTER ROLE

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 user3
           List of roles
 Role name | Attributes | Member of 
-----------+------------+-----------
 user3     |            | {user1}

omm=# revoke user1 from user3;
REVOKE ROLE
omm=# \du user3
           List of roles
 Role name | Attributes | Member of 
-----------+------------+-----------
 user3     |            | {}

5.删除所有创建用户,过程中使用\du或\du+查看用户信息

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                                                                                                      
| {}
 user20    | Create DB                                                                                                        
| {}
 user3     |                                                                                                                  
| {}

omm=# drop user user1;
DROP ROLE
omm=# drop user user20;
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 
| {}

通过学习和作业，对openGauss创建用户、修改用户属性、更改用户权限和删除用户的学习。用户是用来登录数据库的，通过对用户赋予不同的权限，可以方便地管理用户对数据库的访问及操作。