课程作业

1、创建test10_tbs的表空间，在这个表空间中创建数据库testdb10

root@modb:~# su - omm
omm@modb:~$ gsql -r
gsql ((openGauss 3.0.0 build 02c14696) compiled at 2022-04-01 18:12:00 commit 0 last mr  )
Non-SSL connection (SSL connection is recommended when requiring high-security)
Type "help" for help.
--创建表空间
omm=# create tablespace test10_tbs RELATIVE LOCATION 'tablespace/test10_tbs1';
CREATE TABLESPACE
--创建数据库
omm=# create database testdb10 tablespace test10_tbs;
CREATE DATABASE

2、使用create user创建用户user10，登录数据库testdb10，创建测试表t1和t2

--创建用户
omm=# create user user10 identified by "YangKai1111";
NOTICE:  The encrypted password contains MD5 ciphertext, which is not secure.
CREATE ROLE
--授权
omm=# alter user user10 sysadmin;
ALTER ROLE
--登录
omm=# \c testdb10 user10
Password for user user10: 
Non-SSL connection (SSL connection is recommended when requiring high-security)
You are now connected to database "testdb10" as user "user10".
--创建测试表t1和t2
testdb10=> create table t1(id int,name char(20));
CREATE TABLE
testdb10=> create table t2(id int,name char(20)); 
CREATE TABLE

3、使用create role创建角色role10，登录数据库testdb10

--创建角色
omm=# create role role10 identified by "YangKai1111";
NOTICE:  The encrypted password contains MD5 ciphertext, which is not secure.
CREATE ROLE
omm=# alter role role10 sysadmin;
ALTER ROLE
omm=# \c testdb10 role10
Password for user role10: 
FATAL:  role "role10" is not permitted to login
Previous connection kept
--授权角色登录权限
omm=# alter role role10 login;
omm=# ALTER ROLE
omm=#  \c testdb10 role10
Password for user role10: 
Non-SSL connection (SSL connection is recommended when requiring high-security)
You are now connected to database "testdb10" as user "role10".

4、将表t1直接删除，将前面创建的表空间和数据库、表t2转给role10，删除用户user10

--将表t1直接删除
testdb10=> drop table t1;
DROP TABLE
--将前面创建的表空间test10_tbs 和数据库testdb10 转给role10
testdb10=> alter tablespace test10_tbs owner to role10;
ALTER TABLESPACE
testdb10=> alter database testdb10 owner to role10;
ALTER DATABASE
--表t2转给role10
testdb10=> REASSIGN OWNED BY user10 to role10;
REASSIGN OWNED
testdb10=> \dt
                     List of relations
Schema | Name | Type  | Owner  |             Storage              
--------+------+-------+--------+----------------------------------
public | t2   | table | role10 | {orientation=row,compression=no}
(1 row)

omm@modb:~$ gsql -r
gsql ((openGauss 3.0.0 build 02c14696) compiled at 2022-04-01 18:12:00 commit 0 last mr  )
Non-SSL connection (SSL connection is recommended when requiring high-security)
Type "help" for help.
--收回用户所有权限
omm=# REVOKE ALL ON DATABASE testdb10 from user10;
REVOKE
--删除用户
omm=# drop user user10;
DROP ROLE

5、最后删除role10

--删除t2表
omm=# \c testdb10 role10
testdb10=> drop table t2;
DROP TABLE
--收回权限
omm=# REVOKE ALL ON DATABASE testdb10 from role10;
REVOKE
omm=# REVOKE ALL tablespace test10_tbs from role10;
REVOKE
--更改表空间、数据库转用户omm
omm=# alter tablespace test10_tbs owner to omm;
ALTER TABLESPACE
omm=# alter database testdb10 owner to omm;
ALTER DATABASE
--删除角色
omm=# drop role role10;
DROP ROLE

6.总结

在openGauss里用户和角色的功能基本一样，唯一区别角色需要授权登录权限。