openGauss每日一练第5天|多数据库访问

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music_tbs10、测试数据库musicdb10
drop DATABASE  IF EXISTS  musicdb10;
drop tablespace IF EXISTS music_tbs10;
CREATE TABLESPACE music_tbs10 RELATIVE LOCATION 'tablespace/Mygstest_ts10';
CREATE DATABASE musicdb10  WITH TABLESPACE = music_tbs10;
--创建用户user10：
CREATE USER user10 IDENTIFIED BY 'Mygstest@1234';
--授予user10数据库系统的SYSADMIN权限：
ALTER USER user10 SYSADMIN;

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=# drop DATABASE  IF EXISTS  musicdb10;
NOTICE:  database "musicdb10" does not exist, skipping
DROP DATABASE
omm=# drop tablespace IF EXISTS music_tbs10;
omm=# NOTICE:  Tablespace "music_tbs10" does not exist, skipping.
DROP TABLESPACE
CREATE TABLESPACE music_tbs10 RELATIVE LOCATION 'tablespace/Mygstest_ts10';
CREATE TABLESPACE
omm=# CREATE DATABASE musicdb10  WITH TABLESPACE = music_tbs10;
CREATE DATABASE
omm=# CREATE USER user10 IDENTIFIED BY 'Mygstest@1234';
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

--以用户user10的身份在数据库postgres中创建表mytest1，并插入数据：
\c postgres user10 
create table mytest1(product_id INTEGER,product_name Char(20),category Char(30));
insert into mytest1 values(1502,'olympus camera','electrncs'),(1601,'lamaze','toys'),(1700,'wait interface','Books'),(1666,'harry potter','toys');
select * from mytest1;

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 mytest1(product_id INTEGER,product_name Char(20),category Char(30));
CREATE TABLE
openGauss=> insert into mytest1 values(1502,'olympus camera','electrncs'),(1601,'lamaze','toys'),(1700,'wait interface','Books'),(1666,'harry potter','toys');
INSERT 0 4
openGauss=> select * from mytest1;
 product_id |     product_name     |            category            
------------+----------------------+--------------------------------
       1502 | olympus camera       | electrncs                     
       1601 | lamaze               | toys                          
       1700 | wait interface       | Books                         
       1666 | harry potter         | toys                          
(4 rows)

openGauss=> 

3.用户user10访问数据库omm，创建一个表并插入数据

--以用户user10的身份在数据库omm中创建表mytest2，并插入数据：
\c omm user10
create table mytest2(product_id INTEGER,product_name Char(20),category Char(30));
insert into mytest2 values(1502,'olympus camera','electrncs'),(1601,'lamaze','toys'),(1700,'wait interface','Books'),(1666,'harry potter','toys');
select * from mytest2;

omm=# \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 mytest2(product_id INTEGER,product_name Char(20),category Char(30));
omm=> CREATE TABLE
omm=>insert into mytest1 values(1502,'olympus camera','electrncs'),(1601,'lamaze','toys'),(1700,'wait interface','Books'),(1666,'harry potter','toys');
INSERT 0 4
omm=> select * from mytest2;
 product_id |     product_name     |            category            
------------+----------------------+--------------------------------
       1502 | olympus camera       | electrncs                     
       1601 | lamaze               | toys                          
       1700 | wait interface       | Books                         
       1666 | harry potter         | toys                          
(4 rows)

4.用户user10访问数据库musicdb10，创建一个表并插入数据

--以用户user10的身份在数据库musicdb10中创建表mytest3，并插入数据：
\c musicdb10 user10
create table mytest3(product_id INTEGER,product_name Char(20),category Char(30));
insert into mytest3 values(1502,'olympus camera','electrncs'),(1601,'lamaze','toys'),(1700,'wait interface','Books'),(1666,'harry potter','toys');
select * from mytest3;

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 mytest3(product_id INTEGER,product_name Char(20),category Char(30));
CREATE TABLE
musicdb10=> insert into mytest3 values(1502,'olympus camera','electrncs'),(1601,'lamaze','toys'),(1700,'wait interface','Books'),(1666,'harry potter','toys');
INSERT 0 4
musicdb10=> select * from mytest3;
 product_id |     product_name     |            category            
------------+----------------------+--------------------------------
       1502 | olympus camera       | electrncs                     
       1601 | lamaze               | toys                          
       1700 | wait interface       | Books                         
       1666 | harry potter         | toys                          
(4 rows)

musicdb10=>