openGauss每日一练第4天 | 学习心得体会

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

【前言】准备测试环境：

root@modb:~# su - omm
omm@modb:~$ gsql -r
--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';
omm=# CREATE DATABASE musicdb  WITH TABLESPACE = music_tbs;

执行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\du 验证：

omm-# \du
                                                               List of roles
+-----------+-------------------------------------------------------------------------------
-----------------------------------+-----------+
| Role name |                                                    Attributes                 
                                   | Member of |
+-----------+-------------------------------------------------------------------------------
-----------------------------------+-----------+
| gaussdb   | Sysadmin                                                                      
                                   | {}        |
| omm       | Sysadmin, Create role, Create DB, Replication, Administer audit, Monitoradmin,
 Operatoradmin, Policyadmin, UseFT | {}        |
| user1     | Sysadmin                                                                      
                                   | {}        |
| user2     | Sysadmin                                                                      
                                   | {}        |
| user3     | Sysadmin                                                                      
                                   | {}        |
+-----------+-------------------------------------------------------------------------------
-----------------------------------+-----------+

omm-#                                                                

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

1、创建musicdb2数据库。

omm=# CREATE DATABASE musicdb2  WITH TABLESPACE = music_tbs;
CREATE DATABASE

2、以用户user1的身份在数据库musicdb2中创建表products1，并插入数据：

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(product_id INTEGER,product_name char(20),category char(30));
CREATE TABLE
musicdb2=> insert into products1 (product_id,product_name,category) values (1502,'olympus camera','electrncs');
INSERT 0 1
musicdb2=> insert into products1 (product_id,product_name,category) values (1601,'lamaze','toys');
INSERT 0 1
musicdb2=> insert into products1 (product_id,product_name,category) values (1700,'wait interface','Books');
INSERT 0 1
musicdb2=> insert into products1 (product_id,product_name,category) values (1666,'harry potter','toys');
INSERT 0 1
musicdb2=>

3、同理，以用户user2的身份在数据库musicdb2中创建表products2，并插入数据：

omm=# \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(product_id INTEGER,product_name char(20),category char(30));
CREATE TABLE
musicdb2=> insert into products2 (product_id,product_name,category) values (1502,'olympus camera','electrncs');
INSERT 0 1
musicdb2=> insert into products2 (product_id,product_name,category) values (1601,'lamaze','toys');
INSERT 0 1
musicdb2=> insert into products2 (product_id,product_name,category) values (1700,'wait interface','Books');
INSERT 0 1
musicdb2=> insert into products2 (product_id,product_name,category) values (1666,'harry potter','toys');
INSERT 0 1

4、同理，以用户user3的身份在数据库musicdb2中创建表products3，并插入数据：

omm=# \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 (product_id INTEGER,product_name char(20),category char(30));
CREATE TABLE
musicdb2=> insert into products3 (product_id,product_name,category) values (1502,'olympus camera','electrncs');
INSERT 0 1
musicdb2=> 

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

使用\dt 查询

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)