openGauss每日一练第5天 | openGauss中一个用户可以访问多个数据库

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

--创建表空间、测试数据库
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=# \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
(4 rows)

omm=# CREATE TABLESPACE music_tbs RELATIVE LOCATION 'tablespace/music_ts1';
CREATE TABLESPACE
omm=# CREATE DATABASE musicdb10  WITH TABLESPACE = music_tbs;
CREATE DATABASE
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)

--执行下面的SQL语句，创建用户user10：

omm=# CREATE USER user10 IDENTIFIED BY 'kunpeng@2022';
NOTICE:  The encrypted password contains MD5 ciphertext, which is not secure.
CREATE ROLE

--授予user1数据库系统的SYSADMIN权限：

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 t_pg(col1 char(30));
CREATE TABLE
openGauss=> insert into t_pg values('Hello openGauss! postgres');
INSERT 0 1
openGauss=> select * from t_pg;
              col1              
--------------------------------
 Hello openGauss! postgres     
(1 row)

openGauss=> \dt
 public | t_pg | table | user10 | {orientation=row,compression=no}
(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 t_omm(col1 char(30));
CREATE TABLE
omm=> insert into t_omm values('Hello openGauss! omm');
INSERT 0 1
omm=> select * from t_omm;
              col1              
--------------------------------
 Hello openGauss! omm          
(1 row)
 
omm=> \dt
                         List of relations
 Schema | Name  | Type  | Owner  |             Storage              
--------+-------+-------+--------+----------------------------------
 user10 | t_omm | table | user10 | {orientation=row,compression=no}
(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 t10(col1 char(30));
CREATE TABLE
musicdb10=> insert into t10 values('Hello openGauss! t10');
INSERT 0 1
musicdb10=> select * from t10;
              col1              
--------------------------------
 Hello openGauss! t10          
(1 row)

musicdb10=> \dt
                         List of relations
 Schema | Name | Type  | Owner  |             Storage              
--------+------+-------+--------+----------------------------------
 public | t10  | table | user10 | {orientation=row,compression=no}
(1 row)