# rpm -qa | grep mysql
# rpm -qa | grep mariadb
# yum -y remove mysql*
# yum -y remove mariadb*

# rpm -e filename

# find / -name mysql

# useradd mysql -s /sbin/nologin
# id mysql
uid=1000(mysql) gid=1000(mysql) groups=1000(mysql)

mkdir -p /app/database/

mkdir -p /data/3306/

mkdir -p /binlog/3306/

chown -R mysql.mysql /app/ /data/ /binlog/

# firewall-cmd --zone=public --add-port=3306/tcp --permanent
# systemctl restart firewall

# cd /app/database/

# tar -xzvf mysql-8.0.28-linux-glibc2.12-x86_64.tar.xz

# ln -s mysql-8.0.28-linux-glibc2.12-x86_64 mysql

# cd /app/database/msyql
# chown -R mysql.mysql *

# vim /etc/profile

# export PATH=/app/database/mysql/bin:$PATH

# source /etc/profile

# mysql -V
mysql  Ver 8.0.28 for Linux on x86_64 (MySQL Community Server - GPL)

# vim /etc/my.cnf

[mysqld]
basedir=/app/database/mysql
bind-address=0.0.0.0
datadir=/data/3306
log-error=/data/3306/mysql.err
lower-case-table-names=1
pid-file=/data/3306/mysql.pid
port=3306
server_id=1
socket=/tmp/mysql.sock
user=mysql
#character config
character_set_server=utf8mb4
symbolic-links=0

[mysql]
socket=/tmp/mysql.sock

# cd /app/database/mysql/bin
# ./mysqld --initialize-insecure --user=mysql --basedir=/app/database/mysql --datadir=/data/3306/ --defaults-file=/etc/my.cnf --lower-case-table-names=1

cat /data/3306/mysql.err

# cd /app/database/mysql/support-files/

# cp mysql.server /etc/init.d/mysqld

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

# chkconfig --add mysqld
# chkconfig mysqld on

# mysqladmin -uroot -p password iaoexl.1#

# mysql -uroot -p -P3306 -h127.0.0.1
Passwords:

mysql > exit;
mysql > quit;
mysql > \q;

mysql>use mysql;
mysql>update user set host ='%'where user ='root' and host ='localhost';
mysql>flush privileges;