学习目标
掌握openGauss的用户和角色管理。
课程学习
使用create user创建的用户与使用create role创建的用户的区别在于，前者可以直接连接登录数据库，而使用create role创建的用户不能直接登录到数据库。必须添加LOGIN权限后，才能登录到数据库管理系统。
删除用户，首先需要将用户拥有的数据库对象转移或者删除。
1.环境准备
创建一个名叫test_tbs的表空间和一个名叫testdb的数据库：
gsql -r
CREATE TABLESPACE test_tbs RELATIVE LOCATION 'tablespace/test_tbs1';
CREATE DATABASE testdb WITH TABLESPACE = test_tbs;
2.使用create user创建用户
使用create user创建的用户，具有登录权限。
--创建一个名叫user1的数据库用户，其密码为kunpeng@1234，并将数据库testdb所有的权限都授予用户user1：
CREATE USER user1 IDENTIFIED BY 'kunpeng@1234';
GRANT ALL ON DATABASE testdb TO user1;
--执行下面的gsql元命令，查看系统目前有哪些数据库：
\l
--执行下面的gsql元命令，查看系统目前有哪些用户：
\du
\q
--用刚刚创建的数据库用户user1登录到数据库testdb
gsql -d testdb -U user1 -W kunpeng@1234 -r
\q
omm=# create tablespace test_tbs relative location 'tablespace/test_tbs1';\
CREATE TABLESPACE
omm=# create database testdb with tablespace=test_tbs;
CREATE DATABASE
omm=# create user user1 identified by 'kunpeng@1234';
NOTICE: The encrypted password contains MD5 ciphertext, which is not secure.
CREATE ROLE
omm=# grant all on database testdb to user1;
GRANT
omm=# \l
List of databases
Name | Owner | Encoding | Collate | Ctype | Access privileges
-----------+-------+----------+---------+-------+-------------------
omm | omm | UTF8 | C | C |
postgres | omm | UTF8 | C | C |
template0 | omm | UTF8 | C | C | =c/omm +
| | | | | omm=CTc/omm
template1 | omm | UTF8 | C | C | =c/omm +
| | | | | omm=CTc/omm
testdb | omm | UTF8 | C | C | =Tc/omm +
| | | | | omm=CTc/omm +
| | | | | user1=CTc/omm +
| | | | | user1=APm/omm
(5 rows)
omm=# \du
List of roles
Role name | Attributes
| Member of
-----------+-------------------------------------------------------------------------
gaussdb | Sysadmin
| {}
omm | Sysadmin, Create role, Create DB, Replication, Administer audit, Monitor
admin, Operatoradmin, Policyadmin, UseFT | {}
user1 |
| {}
omm=# \q
omm@modb:~$ gsql -d testdb -Uuser1 -Wkunpeng@1234 -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.
testdb=> \q3.使用create role创建用户
使用create role命令创建的用户user2，没有登录权限。
--创建一个新的名叫user2的角色，并将数据库testdb所有的权限都授予用户user2：
用户user2对数据库testdb具有的权限和用户user1一模一样。
gsql -r
CREATE ROLE user2 IDENTIFIED BY 'kunpeng@1234';
GRANT ALL ON DATABASE testdb TO user2;
--查看当前openGauss数据库集群由哪些用户：
\du
\q
--使用用户user2尝试登录到数据库testdb：
gsql -d testdb -U user2 -W kunpeng@1234 -r
gsql: FATAL: role "user2" is not permitted to login
omm=# create role user2 identified by 'kunpeng@1234';
NOTICE: The encrypted password contains MD5 ciphertext, which is not secure.
CREATE ROLE
omm=# grant all on database testdb to user2;
GRANT
omm=# \du
List of roles
Role name | Attributes
| Member of
-----------+-------------------------------------------------------------------------
gaussdb | Sysadmin
| {}
omm | Sysadmin, Create role, Create DB, Replication, Administer audit, Monitor
admin, Operatoradmin, Policyadmin, UseFT | {}
user1 |
| {}
user2 | Cannot login
| {}
omm=# \q
omm@modb:~$ gsql -dtestdb -Uuser2 -Wkunpeng@1234 -r
gsql: FATAL: role "user2" is not permitted to login
omm@modb:~$ 原因：
由于数据库用户user2是使用create role语句创建的，目前还不被允许登录到openGauss数据库管理系统。
4.授予用户user2登录权限后：
授予用户user2登录权限后，可以登录数据库
gsql -r
alter user user2 LOGIN;
\du
\q
--现在我们已经授予了user2用户登录数据库的权限，可以正常登录数据库testdb：
gsql -d testdb -U user2 -W kunpeng@1234 -r
\q
omm=# alter user user2 login; ALTER ROLE omm=# \du List of roles Role name | Attributes | Member of -----------+----------------------------------------------------- gaussdb | Sysadmin | {} omm | Sysadmin, Create role, Create DB, Replication, Administer audit, Monitor admin, Operatoradmin, Policyadmin, UseFT | {} user1 | | {} user2 | | {} omm=# \q omm@modb:~$ gsql -dtestdb -Uuser2 -Wkunpeng@1234 -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. testdb=>- 删除用户和角色
删除用户，首先需要将用户拥有的数据库对象转移或者删除，回收权限。
-- 授予用户user2数据库超级用户的权限：
gsql -r
ALTER USER user2 SYSADMIN;
--使用用户user2登录到数据库testdb，创建表空间test_tbs1、数据库testdb、表test1和表test2：
\c testdb user2
CREATE TABLESPACE test_tbs1 RELATIVE LOCATION 'tablespace/test_tbs11';
CREATE DATABASE testdb WITH TABLESPACE = test_tbs1;
CREATE TABLE test1(col int);
CREATE TABLE test2(col int);
\q
--执行如下的命令，删除用户user2：
gsql -r
drop user user2;
ERROR: role "user2" cannot be dropped because some objects depend on it
DETAIL: owner of database testdb
owner of tablespace test_tbs1
privileges for database testdb
2 objects in database testdb
omm=# alter user user2 sysadmin;
ALTER ROLE
omm=# \c testdb user2;
Password for user user2:
Non-SSL connection (SSL connection is recommended when requiring high-security)
You are now connected to database "testdb" as user "user2".
testdb=> create tablespace test_tbs1 relative location 'tablespace/test_tbs11';
CREATE TABLESPACE
testdb=> create database testdb with tablespace=test_tbs1;
ERROR: database "testdb" already exists
testdb=> create database testdb2 with tablespace=test_tbs1;
CREATE DATABASE
testdb=> create table test1(col int);
CREATE TABLE
testdb=> create table test2(col int);
CREATE TABLE
testdb=> \q
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.
omm=# drop user user2;
ERROR: role "user2" cannot be dropped because some objects depend on it
DETAIL: owner of database testdb2
owner of tablespace test_tbs1
privileges for database testdb
2 objects in database testdb
omm=# ###可以看出不能删除用户user2的原因是：
1）用户user2拥有数据库testdb。
2）用户user2拥有表空间对象test_tbs1。
3）用户user2对数据库testdb具有权限。
4）用户user2在数据库testdb中有两个对象。
--要删除用户user2，必须先表空间对象和数据库对象的属主修改为其他的用户（如user1用户），或者干脆将其删除：
alter database testdb owner to user1;
alter tablespace test_tbs1 owner to user1;
--回收用户user2对testdb数据库的权限：
REVOKE ALL ON DATABASE testdb FROM user2;
--在testdb中属于用户user2的数据库对象的处理方法可以是：假如该对象还有用，可以将该对象转移给其他用户；假如该对象没有用，可以直接删除掉该对象
--假设表test1已经没有用了，我们可以删除表test1：
\c testdb user2
drop table test1;
--假设表test2还有用将表test2转移给用户user1：
REASSIGN OWNED BY user2 to user1;
\dt
\q
--执行删除用户的操作,可以删除user2用户
gsql -r
drop user user2;
\du
omm=# alter database test2 owner to user1;
ERROR: database "test2" does not exist
omm=# alter database testdb2 owner to user1;
ALTER DATABASE
omm=# alter tablespace test_tbs1 owner to user1;
ALTER TABLESPACE
omm=# revoke all on database testdb from user2;
REVOKE
omm=# \c testdb user2
Password for user user2:
FATAL: Invalid username/password,login denied.
Previous connection kept
omm=# \c testdb user2
Password for user user2:
Non-SSL connection (SSL connection is recommended when requiring high-security)
You are now connected to database "testdb" as user "user2".
testdb=> drop table test1;
testdb=> DROP TABLE
testdb=> reassign owner by user2 to user1;
ERROR: syntax error at or near "owner"
LINE 1: reassign owner by user2 to user1;
^
testdb=> reassign owned by user2 to user1;
REASSIGN OWNED
testdb=> \dt
List of relations
Schema | Name | Type | Owner | Storage
--------+-------+-------+-------+----------------------------------
public | test2 | table | user1 | {orientation=row,compression=no}
(1 row)
testdb=> \q
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.
omm=# drop user user2;
DROP ROLE
omm=# \du
-----------------------------------------+-----------
gaussdb | Sysadmin
| {}
omm | Sysadmin, Create role, Create DB, Replication, Administer audit, Monitor
admin, Operatoradmin, Policyadmin, UseFT | {}
user1 |
| {}
List of roles
Role name | Attributes
| Member of
-----------+------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
omm=# create tablespace test10_tbs relative location 'tablespace/testtbs10';
CREATE TABLESPACE
omm=# create database testdb10 with tablespace=test10_tbs;
CREATE DATABASE2、使用create user创建用户user10，登录数据库testdb10，创建测试表t1和t2
mm=# create tablespace test10_tbs relative location 'tablespace/testtbs10';
CREATE TABLESPACE
omm=# create database testdb10 with tablespace=test10_tbs;
CREATE DATABASE
omm=# create user user10 identified by 'kunpeng@1234';
NOTICE: The encrypted password contains MD5 ciphertext, which is not secure.
CREATE ROLE
omm=# grant all ono database testdb10 to user10; database testdb10 to user10;
GRANT
omm=# grant all on database testdb10 to user10;
GRANT
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".
testdb10=> create table t1(col1 int);
ERROR: permission denied for schema public
DETAIL: N/A
omm=# alter user user10 sysadmin;
ALTER ROLE
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".
testdb10=> create table t1(col int);
CREATE TABLE
testdb10=> create table t2(col int);
CREATE TABLE
testdb10=> 3、使用create role创建角色role10，登录数据库testdb10
omm=# create role role10 identified by 'kunpeng@1234';
NOTICE: The encrypted password contains MD5 ciphertext, which is not secure.
CREATE ROLE
omm=# grant all on database testdb10 to role10;
GRANT
omm=# \uomm=#
Invalid command \u. Try \? for help.
omm=# \c testdb10 role10
Password for user role10:
FATAL: role "role10" is not permitted to login
Previous connection kept
omm=# alter user role10 login;
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".
testdb10=> 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
omm=# alter database t2 owner to user10;
omm=# \c testdb10
Non-SSL connection (SSL connection is recommended when requiring high-security)
You are now connected to database "testdb10" as user "omm".
testdb10=# \dt;
List of relations
Schema | Name | Type | Owner | Storage
--------+------+-------+--------+----------------------------------
public | t2 | table | user10 | {orientation=row,compression=no}
(1 row)
omm=# alter database testdb10 owner to role10;
ALTER DATABASE
omm=# alter tablespace test10_tbs owner to role10;
ALTER TABLESPACE
omm=# revoke all on database testdb10 from 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".
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)
testdb10=> \q
omm=# drop user user10;
DROP ROLE5、最后删除role10
omm=# drop role role10;
ERROR: role "role10" cannot be dropped because some objects depend on it
DETAIL: owner of tablespace test10_tbs
owner of database testdb10
1 object in database testdb10
omm=# drop database testdb10;
DROP DATABASE
omm=# drop tablespace test10_tbs;
DROP TABLESPACE
omm=# drop role role10;
DROP ROLE
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