openGauss 每日一练第二轮第4天 | 学习openGauss中一个数据库可以被多个用户访问

第4天 | openGauss中一个数据库可以被多个用户访问

学习目标
学习openGauss体系结构，使用多个用户访问同一个数据库

课程学习
创建user1、user2、user3用户，验证数据库musicdb可以被用户user1、user2、user3访问（分别在数据库中创建了一张表、插入数据、进行查询）。即一个数据库可以被多个用户访问。

1.测试环境准备：

Welcome to 墨天轮.
This is Web Terminal of modb.pro; Good Good Study, Day Day Up.

root@modb:~#

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.

omm=#

--进入数据库omm，创建表空间、测试数据库
omm=# CREATE TABLESPACE music_tbs RELATIVE LOCATION 'tablespace/test_ts1';
CREATE TABLESPACE
omm=# CREATE DATABASE musicdb WITH TABLESPACE = music_tbs;
CREATE DATABASE

2.创建用户user1、user2、user3

--执行下面的SQL语句，创建用户user1、user2、user3：

omm=# CREATE USER user1 IDENTIFIED BY 'kunpeng@1234';
NOTICE: The encrypted password contains MD5 ciphertext, which is not secure.
CREATE ROLE
omm=# CREATE USER user2 IDENTIFIED BY 'kunpeng@1234';
NOTICE: The encrypted password contains MD5 ciphertext, which is not secure.
CREATE ROLE
omm=# CREATE USER user3 IDENTIFIED BY 'kunpeng@1234';
NOTICE: The encrypted password contains MD5 ciphertext, which is not secure.
CREATE ROLE

--授予user1、user2、user3数据库系统的SYSADMIN权限：
omm=# ALTER USER user1 SYSADMIN;
ALTER ROLE
omm=# ALTER USER user2 SYSADMIN;
ALTER ROLE
omm=# ALTER USER user3 SYSADMIN;
ALTER ROLE
--执行下面的命令，查看有哪些用户：
omm=# \du
List of roles
Role name | Attributes
| Member of
user3 | Sysadmin
| {}

-----------+-----------------------------------------------------------------------------------
-------------------------------+-----------
gaussdb | Sysadmin
| {}
omm | Sysadmin, Create role, Create DB, Replication, Administer audit, Monitoradmin, Ope
ratoradmin, Policyadmin, UseFT | {}
user1 | Sysadmin
| {}
user2 | Sysadmin
| {}

2.在终端中，分别使用user1、user2、user3用户访问数据库musicdb。
--以用户user1的身份在数据库musicdb中创建表t1，并插入一条数据：
omm=# \c musicdb user1
Password for user user1:
Non-SSL connection (SSL connection is recommended when requiring high-security)
You are now connected to database "musicdb" as user "user1".
musicdb=> create table t1(col1 char(20));
CREATE TABLE
musicdb=> insert into t1 values('Hello kunpeng 1');
INSERT 0 1
musicdb=> select * from t1;
musicdb=> col1
----------------------
Hello kunpeng 1
(1 row)

--以用户user2的身份在数据库musicdb中创建表t2，并插入一条数据：

musicdb=> \c musicdb user2
Password for user user2:
Non-SSL connection (SSL connection is recommended when requiring high-security)
You are now connected to database "musicdb" as user "user2".
musicdb=> create table t2(col1 char(20));
CREATE TABLE
musicdb=> insert into t2 values('Hello kunpeng 2');
INSERT 0 1
musicdb=> select * from t2;
col1
----------------------
Hello kunpeng 2
(1 row)
--以用户user3的身份在数据库musicdb中创建表t3，并插入一条数据：
musicdb=> \c musicdb user3
Password for user user3:
Non-SSL connection (SSL connection is recommended when requiring high-security)
You are now connected to database "musicdb" as user "user3".
musicdb=> create table t3(col1 char(20));
CREATE TABLE
musicdb=> insert into t3 values('Hello kunpeng 3');
INSERT 0 1
musicdb=> select * from t3;
col1
----------------------
Hello kunpeng 3
(1 row)
3.使用user1、user2、user3用户中的任何一个，执行如下命令，查看当前数据库musicdb有哪些表：

musicdb=> \dt
List of relations
Schema | Name | Type | Owner | Storage
--------+------+-------+-------+----------------------------------
public | t1 | table | user1 | {orientation=row,compression=no}
public | t2 | table | user2 | {orientation=row,compression=no}
public | t3 | table | user3 | {orientation=row,compression=no}
(3 rows)


课后作业
1.创建用户user1、user2、user3，授予user1、user2、user3数据库系统的SYSADMIN权限
#创建用户
omm=# CREATE USER user1 IDENTIFIED BY 'kunpeng@1234';
NOTICE: The encrypted password contains MD5 ciphertext, which is not secure.
CREATE ROLE
omm=# CREATE USER user2 IDENTIFIED BY 'kunpeng@1234';
NOTICE: The encrypted password contains MD5 ciphertext, which is not secure.
CREATE ROLE
omm=# CREATE USER user3 IDENTIFIED BY 'kunpeng@1234';
NOTICE: The encrypted password contains MD5 ciphertext, which is not secure.
CREATE ROLE
#赋sysadmin权限
omm=# ALTER USER user1 SYSADMIN;
ALTER ROLE
omm=# ALTER USER user2 SYSADMIN;
ALTER ROLE
omm=# ALTER USER user3 SYSADMIN;
ALTER ROLE


2.分别使用user1、user2、user3访问数据库musicdb2，创建各自的表，并插入数据。表名和数据如下：

表名分别为： products1、 products2、 products3

字段名 数据类型 含义
product_id INTEGER 产品编号
product_name Char(20) 产品名
category Char(30) 种类
向表中插入数据：

product_id product_name category
1502 olympus camera electrncs
1601 lamaze toys
1700 wait interface Books
1666 harry potter toys

#创建表空间
omm=# CREATE TABLESPACE music2_tbs RELATIVE LOCATION 'tablespace/test_ts2';
CREATE TABLESPACE
#创建数据库
omm=# CREATE DATABASE musicdb2 WITH TABLESPACE = music2_tbs;
CREATE DATABASE

#连接user1建表插入数据

omm=# \c musicdb2 user1
Password for user user1:
Non-SSL connection (SSL connection is recommended when requiring high-security)
You are now connected to database "musicdb2" as user "user1".
musicdb2=> CREATE TABLE products1
musicdb2-> (
musicdb2(> product_id integer,
musicdb2(> musicdb2(> product_name char(20),
category char(30)
musicdb2(> );
musicdb2=> CREATE TABLE


musicdb2=> comment on COLUMN products1.product_id IS '产品编号';
COMMENT
musicdb2=> comment on COLUMN products1.product_name IS '产品名';
COMMENT
musicdb2=> comment on COLUMN products1.category IS '种类';
COMMENT

musicdb2=> insert into products1 values(1502,'olympus camera','electrncs');
INSERT 0 1
musicdb2=> insert into products1 values(1601,'lamaze','toys');
INSERT 0 1
musicdb2=> insert into products1 values(1700,'wait interface','Books');
INSERT 0 1
musicdb2=> insert into products1 values(1666,'harry potter','toys');
INSERT 0 1
#连接user2建表插入数据

musicdb2=> \c musicdb2 user2
Password for user user2:
Non-SSL connection (SSL connection is recommended when requiring high-security)
You are now connected to database "musicdb2" as user "user2".
musicdb2=> CREATE TABLE products2
musicdb2-> (
musicdb2(> product_id integer,
product_name char(20),
musicdb2(> musicdb2(> musicdb2(> ); category char(30)

CREATE TABLE
musicdb2=> comment on COLUMN products2.product_id IS '产品编号';
COMMENT
musicdb2=> comment on COLUMN products2.product_name IS '产品名';
COMMENT
musicdb2=> comment on COLUMN products2.category IS '种类';
COMMENT

musicdb2=> insert into products2 values(1502,'olympus camera','electrncs');
INSERT 0 1
musicdb2=> insert into products2 values(1601,'lamaze','toys');
INSERT 0 1
musicdb2=> insert into products2 values(1700,'wait interface','Books');
INSERT 0 1
musicdb2=> insert into products2 values(1666,'harry potter','toys');
INSERT 0 1
#连接user3建表插入数据
musicdb2=> \c musicdb2 user3
Password for user user3:
Non-SSL connection (SSL connection is recommended when requiring high-security)
You are now connected to database "musicdb2" as user "user3".

musicdb2=> CREATE TABLE products3
musicdb2-> (
musicdb2(> product_id integer,
musicdb2(> product_name char(20),
musicdb2(> category char(30)
musicdb2(> );
CREATE TABLE

musicdb2=> comment on COLUMN products3.product_id IS '产品编号';
COMMENT
musicdb2=> comment on COLUMN products3.product_name IS '产品名';
COMMENT
musicdb2=> comment on COLUMN products3.category IS '种类';
COMMENT

musicdb2=> insert into products3 values(1502,'olympus camera','electrncs');
INSERT 0 1
musicdb2=> insert into products3 values(1601,'lamaze','toys');
INSERT 0 1
musicdb2=> insert into products3 values(1700,'wait interface','Books');
INSERT 0 1
musicdb2=> insert into products3 values(1666,'harry potter','toys');
INSERT 0 1
3.使用user1、user2、user3用户中的任何一个，查看当前数据库musicdb2有哪些表
musicdb2=> \dt
List of relations
Schema | Name | Type | Owner | Storage
--------+-----------+-------+-------+----------------------------------
public | products1 | table | user1 | {orientation=row,compression=no}
public | products2 | table | user2 | {orientation=row,compression=no}
public | products3 | table | user3 | {orientation=row,compression=no}
(3 rows)