rpm -qa | grep Maria*

yum -y remove mari*

 rm -rf /var/lib/mysql/*

vi /etc/yum.repos.d/MariaDB.repo

# MariaDB 10.3 CentOS repository list - created 2018-06-21 09:11 UTC
# http://downloads.mariadb.org/mariadb/repositories/
[mariadb]
name = MariaDB
# baseurl = http://yum.mariadb.org/10.3/centos7-amd64
# 修改為國內源
baseurl = https://mirrors.shu.edu.cn/mariadb//mariadb-10.3.7/yum/centos7-amd64/
gpgkey=https://yum.mariadb.org/RPM-GPG-KEY-MariaDB
gpgcheck=1
 

sudo yum install MariaDB-server MariaDB-client

service mysql stop
mkdir -p /data/mysqldb
#拷貝預設資料庫到新的位置,-a表示將檔案屬性一起拷貝
cp -a /var/lib/mysql /data/mysqldb

vim /etc/my.cnf.d/server.cnf

    找到[mysqld]，新增以下內容：

[mysqld]
datadir=/data/mysqldb/mysql
socket=/var/lib/mysql/mysql.sock
#default-character-set=utf8 
character_set_server=utf8 
slow_query_log=on 
slow_query_log_file=/data/mysqldb/slow_query_log.log  
long_query_time=2 
 

touch /data/mysqldb/slow_query_log.log
chmod 666 /data/mysqldb/slow_query_log.log

service mysql start

    可使用命令修改：

mysqladmin -u root password 'root'

    或者通過執行安全策略修改：

/usr/bin/mysql_secure_installation

    root原始密碼存在於：/root/.mysql_secret

mysql -u root -p

grant all on *.* to 'root'@'%' identified by 'password' with grant option; 
 

service mysql start
service mysql stop
service mysql restart
service mysql status