记录一下 centos msyql安装步骤

• 下载msyql

  wget https://dev.mysql.com/get/Downloads/MySQL-5.7/mysql-5.7.26-linux-glibc2.12-x86_64.tar.gz

• 解压

  tar -zxvf  mysql-5.7.26-linux-glibc2.12-x86_64.tar.gz

• 重新命名以及移到合适目录

  mv mysql-5.7.26-linux-glibc2.12-x86_64.tar.gz  msyql
  mv mysql-5.7.26-linux-glibc2.12-x86_64.tar.gz  /usr/local/

• 添加用户和组

  groupadd mysql
  useradd -g mysql mysql

• 进入/usr/local/msyql目录,并设置文件到所属者

  chown -R mysql:mysql ./

• 初始化,并记住初始密码

  /usr/local/bin/mysql_install_db --user=mysql --basedir=/usr/local/mysql/ --datadir=/usr/local/mysql/data/

• 用systemctl 代替 service

  [Unit]
  Description=MySQL Server
  Documentation=http://dev.mysql.com/doc/refman/en/using-systemd.html
  After=network.target
  After=syslog.target
  [Install]
  WantedBy=multi-user.target
  [Service]
  User=mysql
  Group=mysql
  PIDFile=/usr/local/mysql/data/mysqld.pid
  # Disable service start and stop timeout logic of systemd for mysqld service.
  TimeoutSec=0
  PermissionsStartOnly=true
  # Start main service
  ExecStart=/usr/local/mysql/bin/mysqld --daemonize --pid-file=/usr/local/mysql/data/mysqld.pid
  # Sets open_files_limit
  LimitNOFILE = 5000
  Restart=on-failure
  RestartPreventExitStatus=1
  PrivateTmp=false

• 设置开启启动并启动mysql

  systemctl enable msyql
  systemctl statr msyql

• 大功高成
  

• 如果不小心忘记密码

  systemctl stop mysql.service
  /usr/local/mysql/bin/mysqld_safe --skip-grant-tables & 

• 然后打开另一个窗口运行下面，即可进入修改密码

  msyql --uroot -p
  //修改
  update mysql.user set authentication_string=password('新的密码') where user='root' and Host = 'localhost';
   flush privileges;

关闭 【-- 如何不小心忘记密码】操作，重新启动即可