一、学习目标
学习openGauss体系结构，使用一个用户访问多个数据库。
二、课程学习
数据库用户user1可以访问不同的数据库（musicdb1、musicdb2、musicdb3）。
实验中user1用户在数据库musicdb1中创建了表t11、在数据库musicdb2创建了表t21、在数据库musicdb3中创建了表t31，验证了这个结论。
三、课程作业
1. 创建数据库musicdb10，创建用户user10，赋予sysadmin权限
su - omm
gsql -r
--进入数据库omm，创建表空间、测试数据库
drop DATABASE IF EXISTS musicdb10;
drop tablespace IF EXISTS music_tbs;
CREATE TABLESPACE music_tbs RELATIVE LOCATION 'tablespace/test_ts1';
CREATE DATABASE musicdb10 WITH TABLESPACE = music_tbs;
--执行下面的SQL语句，创建用户user10：
CREATE USER user10 IDENTIFIED BY 'kunpeng@1234';
--授予user1数据库系统的SYSADMIN权限：
ALTER USER user10 SYSADMIN;
--查看数据库中目前有哪些用户和角色
\du
实训环境示例：
omm=# drop DATABASE IF EXISTS musicdb10;
NOTICE: database "musicdb10" does not exist, skipping
DROP DATABASE
omm=# drop tablespace IF EXISTS music_tbs;
NOTICE: Tablespace "music_tbs" does not exist, skipping.
DROP TABLESPACE
omm=# CREATE TABLESPACE music_tbs RELATIVE LOCATION 'tablespace/test_ts1';
CREATE TABLESPACE
omm=# CREATE DATABASE musicdb10 WITH TABLESPACE = music_tbs;
CREATE DATABASE
omm=# \db
omm=# List of tablespaces
Name | Owner | Location
------------+-------+---------------------
music_tbs | omm | tablespace/test_ts1
pg_default | omm |
pg_global | omm |
(3 rows)
omm=#
\l
List of databases
Name | Owner | Encoding | Collate | Ctype | Access privileges
-----------+-------+----------+---------+-------+-------------------
musicdb10 | omm | UTF8 | C | C |
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
(5 rows)
omm=# CREATE USER user10 IDENTIFIED BY 'kunpeng@1234';
NOTICE: The encrypted password contains MD5 ciphertext, which is not secure.
CREATE ROLE
omm=# ALTER USER user10 SYSADMIN;
ALTER ROLE
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 | {
}
user1 | Sysadmin
| {
}
user10 | Sysadmin
| {
}
omm=#
2. 用户user10访问数据库postgres，创建一个表并插入数据
--用户user10登录到数据库postgres，创建表test1，并插入、查看数据
\c postgres user10
create table test1(id int primary key,col1 char(20));
insert into test1 values(1,'Hello openGauss! 11');
insert into test1 values(2,'Hello openGauss! 11');
select * from test1;
omm=# \c postgres user10
Password for user user10:
Non-SSL connection (SSL connection is recommended when requiring high-security)
You are now connected to database "postgres" as user "user10".
openGauss=> create table test1(id int primary key,col1 char(20));
NOTICE: CREATE TABLE / PRIMARY KEY will create implicit index "test1_pkey" for table "test1"
CREATE TABLE
openGauss=> insert into test1 values(1,'Hello openGauss! 11');
INSERT 0 1
openGauss=> insert into test1 values(2,'Hello openGauss! 11');
INSERT 0 1
openGauss=> select * from test1;
id | col1
----+----------------------
1 | Hello openGauss! 11
2 | Hello openGauss! 11
(2 rows)
openGauss=>
3. 用户user10访问数据库omm，创建一个表并插入数据
--用户user10登录到数据库omm，创建表test2，并插入、查看数据
\c omm user10
create table test2(id int primary key,col1 char(20));
insert into test2 values(1,'Hello World! 11');
insert into test2 values(2,'Hello World! 22');
select * from test2;
openGauss=> \c omm user10
Password for user user10:
Non-SSL connection (SSL connection is recommended when requiring high-security)
You are now connected to database "omm" as user "user10".
omm=> create table test2(id int primary key,col1 char(20));
NOTICE: CREATE TABLE / PRIMARY KEY will create implicit index "test2_pkey" for table "test2"
CREATE TABLE
omm=> insert into test2 values(1,'Hello World! 11');
INSERT 0 1
omm=> insert into test2 values(2,'Hello World! 22');
INSERT 0 1
omm=> select * from test2;
id | col1
----+----------------------
1 | Hello World! 11
2 | Hello World! 22
(2 rows)
omm=>
4. 用户user10访问数据库musicdb10，创建一个表并插入数据
--用户user10登录到数据库musicdb10，创建表test3，并插入、查看数据
\c musicdb10 user10
create table test3(id int primary key,col1 char(20),col2 date);
insert into test3 values(1,'Hello World! 11','2022-11-28');
insert into test3 values(2,'Hello World! 22',sysdate);
select * from test3 order by id;
omm=# \c musicdb10 user10
Password for user user10:
Non-SSL connection (SSL connection is recommended when requiring high-security)
You are now connected to database "musicdb10" as user "user10".
musicdb10=> create table test3(id int primary key,col1 char(20),col2 date);
NOTICE: CREATE TABLE / PRIMARY KEY will create implicit index "test3_pkey" for table "test3"
musicdb10=> CREATE TABLE
insert into test3 values(1,'Hello World! 11','2022-11-28');
INSERT 0 1
musicdb10=> insert into test3 values(2,'Hello World! 22',sysdate);
INSERT 0 1
musicdb10=> select * from test3 order by id;
id | col1 | col2
----+----------------------+------------
1 | Hello World! 11 | 2022-11-28
2 | Hello World! 22 | 2022-11-28
(2 rows)
musicdb10=>