MariaDB study notes

install mariadb

If not specified mariadb Of yum Source , Direct installation can also be successful , But the version is 5.5 Should be the default installation version of Alibaba cloud , It is recommended that you try to install a new version .

#  edit yum Source file 
vim /etc/yum.repos.d/epel.repo

#  add to mariadb Of yum Mirror source 
[mariadb]
name = MariaDB
baseurl = http://mirrors.ustc.edu.cn/mariadb/yum/10.3/centos7-amd64/
gpgkey=http://mirrors.ustc.edu.cn/mariadb/yum/RPM-GPG-KEY-MariaDB
gpgcheck=1

#  install mariadb
sudo yum -y install mariadb mariadb-server

#  Start database 
sudo systemctl start mariadb

#  Restart the database 
sudo systemctl restart mariadb

#  Set boot up 
sudo systemctl enable mariadb mariadb
#  Check the database status 
sudo systemctl status mariadb

#  uninstall mariaddb
yum remove mariadb
rm -f /etc/my.cnf
rm -rf /var/lib/mysql/
rpm -qa|grep mariadb

function mariadb Security configuration command

Through execution mysql_secure_installation Make security configuration , Use... According to the actual situation Y/N Answer the following questions ： Set up root password 、 Delete anonymous users 、 Ban root Remote login 、 Delete test database , Reload permission table （ See the picture below ）.

Complete the above security configuration , Re execute the following command

#  Restart the database 
sudo systemctl restart mariadb

#  Check the database status 
sudo systemctl status mariadb

The results are shown in the figure below
From the startup information above, you can see mariadb It's started successfully , And the version is consistent with the information of the image source 10.3 edition

Operation user

#  Login database 
mysql -uroot -p123456

#  Specify database 
use mysql;

#  Query the user 
select user,password,host from user;

#  Create any user ip visit 
create user 'zhangsan'@'%' identified by '123456';

#  Create user specified ip visit 
create user 'lisi'@'102.12.56.3' identified by '123456';

#  Rename user 
rename user 'zhangsan'@'%' to 'zhangsan1'@'%';

#  Delete user 
drop user 'yangxin'@'localhost';

Administrative authority

#  Grant users zhangsan Of blog Database all permissions 
grant all privileges on blog.* to 'zhangsan'@'%' identified by '123456';

#  Grant users zhangsan Of blog Database operation data addition, deletion, modification and query permission 
grant select,insert,update,delete on blog.* to 'zhangsan'@'%' identified by '123456';

#  Grant users zhangsan All database operation permissions 
grant all privileges on *.* to 'zhangsan'@'%' identified by '123456' with grant option;

#  Recycling permissions 
revoke create on *.* from '[email protected]%';
#  Refresh the permissions 
 flush privileges; 

modify root password

Method 1

#  Directly in shell Command line  mysqladm  Command to change ** Need to use root Log in at the terminal **
mysqladmin -uroot -p password newpassword

You will be prompted for the old password , If not set before , Just go straight back .

Method 2

#  Log in to the database to change the password update
use mysql;  
update user set password = password('123456') where user ='root';
SET password for'root'@'localhost'=password('123456');  

#  Remember to refresh permissions 
flush privileges; 

Forget how to change the password

#  close mariadb service 
sudo  systemctl stop mariadb
#  Skip authorization to start  mariadb
mysqld_safe --skip-grant-tables & ps -ef | grep 8690

The operation results are shown in the figure below

When skipping authorization startup , You can do it without a password msyql Login database . At this time, you can change the password in the above way ; When the password is modified , Even if you use an empty password to skip authorization, you cannot log in ; Kill the skip authorization process kill -9 8690, start-up mariadbsudo systemctl start mariadb