openGauss每日一练第5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-学习笔记

课程学习
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

连接openGauss
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.
1.创建用户
–以下两种设置密码方法等效
omm=# CREATE USER jim PASSWORD 'abcd@123';
NOTICE: The encrypted password contains MD5 ciphertext, which is not secure.
CREATE ROLE
omm=# CREATE USER kim IDENTIFIED BY 'abcd@456';
NOTICE: The encrypted password contains MD5 ciphertext, which is not secure.
CREATE ROLE
omm=#
–用户dim具有创建数据库权限
CREATE USER dim CREATEDB PASSWORD 'abcd@789';
NOTICE: The encrypted password contains MD5 ciphertext, which is not secure.
CREATE ROLE
–查看用户
omm=# \du
List of roles
Role name | Attributes
| Member of
-----------+-----------------------------------------------------------------------------------
-------------------------------+-----------
dim | Create DB
| {}
gaussdb | Sysadmin
| {}
jim |
| {}
kim |
| {}
omm | Sysadmin, Create role, Create DB, Replication, Administer audit, Monitoradmin, Ope
ratoradmin, Policyadmin, UseFT | {}
2.修改用户属性
–修改密码
omm=# ALTER USER jim IDENTIFIED BY 'Abcd@123' REPLACE 'abcd@123';
NOTICE: The encrypted password contains MD5 ciphertext, which is not secure.
ALTER ROLE
–为用户jim增加CREATEROLE权限
omm=# ALTER USER jim CREATEROLE;
ALTER ROLE
–查看用户
omm=# \du
List of roles
Role name | Attributes
| Member of
-----------+-----------------------------------------------------------------------------------
-------------------------------+-----------
dim | Create DB
jim | Create role
| {}
kim |
| {}
omm | Sysadmin, Create role, Create DB, Replication, Administer audit, Monitoradmin, Ope
| {}
gaussdb | Sysadmin
| {}
ratoradmin, Policyadmin, UseFT | {}
3.授权
–将用户jim的权限授权给用户kim

omm=# GRANT jim to kim;
GRANT ROLE
–将sysadmin权限授权给用户dim
omm=# GRANT ALL PRIVILEGES TO dim;
ALTER ROLE
–重命名用户dim
omm=# alter user dim rename to tim;~
NOTICE: MD5 password cleared because of role rename
ALTER ROLE
–查看用户
omm-# \du
List of roles
Role name | Attributes
| Member of
-----------+-----------------------------------------------------------------------------------
-------------------------------+-----------
gaussdb | Sysadmin
| {}
jim | Create role
| {}
kim |
| {jim}
omm | Sysadmin, Create role, Create DB, Replication, Administer audit, Monitoradmin, Ope
ratoradmin, Policyadmin, UseFT | {}
tim | Create DB, Sysadmin
| {}

4.回收权限
–撤消kim的权限
omm=# REVOKE jim FROM kim;
REVOKE ROLE

–撤消用户dim的sysadmin权限

omm=# revoke all privilege from tim;
ALTER ROLE

–查看用户
omm=# \du
List of roles
Role name | Attributes
| Member of
-----------+-----------------------------------------------------------------------------------
-------------------------------+-----------
gaussdb | Sysadmin
| {}
omm | Sysadmin, Create role, Create DB, Replication, Administer audit, Monitoradmin, Ope
ratoradmin, Policyadmin, UseFT | {}
tim | Create DB
| {}

jim | Create role
| {}
kim |
| {}

5.删除用户
omm=# drop user tim;
DROP ROLE
omm=# drop user jim;
DROP ROLE
omm=# drop user kim;
DROP ROLE

课程作业
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
CREATE USER user1 CREATEROLE PASSWORD 'test_user1';
CREATE USER user1 CREATEROLE IDENTIFIED BY 'test_user1';
CREATE USER user2 CREATEDB PASSWORD 'test_user2';
CREATE USER user2 CREATEDB IDENTIFIED BY 'test_user2';
CREATE USER user3 PASSWORD 'test_user3';
CREATE USER user3 IDENTIFIED BY 'test_user3';

omm=# CREATE USER user1 CREATEROLE PASSWORD 'test_user1';
NOTICE: The encrypted password contains MD5 ciphertext, which is not secure.
CREATE ROLE
omm=# CREATE USER user2 CREATEDB IDENTIFIED BY 'test_user2';
NOTICE: The encrypted password contains MD5 ciphertext, which is not secure.
CREATE ROLE
omm=# CREATE USER user3 PASSWORD 'test_user3';
NOTICE: The encrypted password contains MD5 ciphertext, which is not secure.
CREATE ROLE
2.修改用户user1的密码
ALTER USER user1 IDENTIFIED BY 'user1@123' REPLACE 'test_user1';

omm=# ALTER USER user1 IDENTIFIED BY 'user1@123' REPLACE 'test_user1';
NOTICE: The encrypted password contains MD5 ciphertext, which is not secure.
ALTER ROLE

3.重命名用户user2
alter user user2 rename to user2_new;
omm=# alter user user2 rename to user2_new;
NOTICE: MD5 password cleared because of role rename
omm=# 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=# revoke user1 from user3;
REVOKE ROLE
5.删除所有创建用户
过程中使用\du或\du+查看用户信息
omm=# drop user user1;
DROP ROLE
omm=# drop user user2_new;
DROP ROLE
omm=# drop user user3;
DROP ROLE
omm=# \du
| {}
omm | Sysadmin, Create role, Create DB, Replication, Administer audit, Monitoradmin, Ope
ratoradmin, Policyadmin, UseFT | {}

List of roles
Role name | Attributes
| Member of
-----------+-----------------------------------------------------------------------------------
-------------------------------+-----------
gaussdb | Sysadmin