openGauss每日一练第 5 天 | 一个用户访问多个数据库

学习目标
学习openGauss体系结构，使用一个用户访问多个数据库。

课程学习
数据库用户user0可以访问不同的数据库（musicdb10、postgres、omm）。

课程作业

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.

1.创建数据库musicdb10，创建用户user10，赋予sysadmin权限

omm=# create tablespace music10_tbs relative location 'tablespace/test_ts10';
CREATE TABLESPACE
omm=# create database musicdb10 with tablespace=music10_tbs;
CREATE DATABASE
omm=# create user user10 identified by 'test@123';
NOTICE:  The encrypted password contains MD5 ciphertext, which is not secure.
CREATE ROLE
omm=# alter user user10 sysadmin;
ALTER ROLE

2.用户user10访问数据库postgres，创建一个表并插入数据

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 t1(id int);
CREATE TABLE
openGauss=> insert into t1 values(10);
INSERT 0 1
openGauss=> select * from t1;
 id 
----
 10
(1 row)

3.用户user10访问数据库omm，创建一个表并插入数据

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 t2(id int);
omm=> CREATE TABLE
insert into t2 values(20);
INSERT 0 1
omm=> select * from t2;
 id 
----
 20
(1 row)

4.用户user10访问数据库musicdb10，创建一个表并插入数据

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 t3(id int);
CREATE TABLE
musicdb10=> insert into t3 values(30);
musicdb10=> INSERT 0 1
select  * from t3;
 id 
----
 30
(1 row)