simply to install mysql for centos7

mysql-install.sh

#!/bin/bash
#only test for centos 7
MYSQL_SERIES=8.0
MYSQL_VERSION=8.0.29
MYSQL_DOWNLOAD_URL=https://dev.mysql.com/get/Downloads/MySQL-${MYSQL_SERIES}/mysql-${MYSQL_VERSION}-el7-x86_64.tar.gz
MYSQL_INSTALL_DIR=/usr/local/mysql
MYSQL_SOURCE_DIR="${MYSQL_INSTALL_DIR}-${MYSQL_VERSION}"
MYSQL_DATA_DIR=/var/lib/mysql
MYSQL_LOG_DIR=/var/log/mariadb
DEFAULT_ROOT_PASSWORD=123456789
function check_error() {
	if [ $? -ne 0 ]; then
		echo $1
		remove
		exit 1
	fi
}
function install() {
        yum install -y libncurses*
	cat << EOT >/etc/my.cnf
[mysqld]
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock
# Disabling symbolic-links is recommended to prevent assorted security risks
symbolic-links=0
lower_case_table_names=0
# Settings user and group are ignored when systemd is used.
# If you need to run mysqld under a different user or group,
# customize your systemd unit file for mariadb according to the
# instructions in http://fedoraproject.org/wiki/Systemd

[mysqld_safe]
log-error=/var/log/mariadb/mariadb.log
pid-file=/var/run/mariadb/mariadb.pid

#
# include all files from the config directory
#
#!includedir /etc/my.cnf.d
EOT
	wget -O /tmp/mysql.tar.gz $MYSQL_DOWNLOAD_URL
	check_error "download mysql.tar.gz error!"
	mkdir $MYSQL_SOURCE_DIR
	tar -zxvf /tmp/mysql.tar.gz --strip-components 1 -C $MYSQL_SOURCE_DIR
	check_error "decompression failed!"
	groupadd mysql
	useradd -r -g mysql -s /bin/false mysql
	ln -s $MYSQL_SOURCE_DIR $MYSQL_INSTALL_DIR
	cd $MYSQL_INSTALL_DIR
	mkdir mysql-files
	chown mysql:mysql mysql-files
	chmod 750 mysql-files
	bin/mysqld --initialize-insecure --user=mysql
	check_error "run initialize failed!"
	bin/mysql_ssl_rsa_setup
	check_error "run mysql_ssl_rsa_setup failed!"
	mkdir $MYSQL_LOG_DIR
	touch ${MYSQL_LOG_DIR}/mariadb.log
	chown -R mysql:mysql $MYSQL_LOG_DIR
	chmod -R 750 $MYSQL_LOG_DIR
	bin/mysqld_safe --user=mysql
	check_error "run mysqld_safe failed!"
	cp support-files/mysql.server /etc/init.d/mysql.server
	cat << EOT > /etc/systemd/system/mysql.service
[unit]
Description=mysql

Wants=network.target
After=syslog.target network-online.target

[Service]
User=mysql
Group=mysql
Type=simple
Environment=GOGC=20
ExecStart=/usr/local/mysql/bin/mysqld
Restart=on-failure
RestartSec=10
KillMode=process
LimitNOFILE=65536

[Install]
WantedBy=multi-user.target
EOT
	systemctl enable --now mysql
	echo "export PATH=\$PATH:${MYSQL_INSTALL_DIR}/bin" >> /root/.bash_profile
	source /root/.bash_profile
	sleep 3s
	mysql -uroot -h127.0.0.1 -e "
	tee /tmp/temp.log
	ALTER USER 'root'@'localhost' IDENTIFIED BY '${DEFAULT_ROOT_PASSWORD}';
	flush privileges;
	notee
	quit"
	bin/mysql_secure_installation -h127.0.0.1 -p${DEFAULT_ROOT_PASSWORD} << EOF
N
N
Y
Y
Y
Y
EOF
	rm -rf /tmp/mysql.tar.gz
	clear
	echo "root password: ${DEFAULT_ROOT_PASSWORD}"
	echo "install finished!"
}

function remove() {
	CONVERTED_MYSQL_INSTALL_DIR=$(echo $MYSQL_INSTALL_DIR | sed 's/\//\\\//g')
	sed -i "/export PATH=\$PATH:${CONVERTED_MYSQL_INSTALL_DIR}\/bin/d" /root/.bash_profile
	source /root/.bash_profile
	systemctl stop mysql
	systemctl disable mysql
	rm -rf /etc/systemd/system/mysql.service
	rm -rf $MYSQL_LOG_DIR
	rm -rf $MYSQL_DATA_DIR
	rm -rf $MYSQL_INSTALL_DIR
	rm -rf $MYSQL_SOURCE_DIR
	userdel mysql
	groupdel mysql
	clear
	echo "remove finished!"
}


function help() {
    cat << EOF
    mysql install helper!!!
    usage: 
    ./mysql.sh menu
    install: install mysql
    remove: remove mysql
EOF
}

function main() {
    if [ $# -lt 1 ]; then
        help
    else
        case $1 in
            install)
                install
            ;;
            remove)
                remove
            ;;
            *)
                echo 'command not found!'
                help
            ;;
        esac
    fi
}

main $@