（實踐應用）CentOS + MySQL5.7 Have No mysqld_safe

https://stackoverflow.com/questions/33510184/change-mysql-root-password-on-centos7/34207996#34207996

• systemd is now used to look after mySQL instead of mysqld_safe (which is why you get the -bash: mysqld_safe: command not found error - it’s not installed)

• The user table structure has changed.

  1. Stop mysql:
     systemctl stop mysqld

  2. Set the mySQL environment option
     systemctl set-environment MYSQLD_OPTS=”–skip-grant-tables”

  3. Start mysql usig the options you just set
     systemctl start mysqld

  4. Login as root
     mysql -u root

  5. Update the root user password with these mysql commands
     mysql> UPDATE mysql.user SET authentication_string = PASSWORD(‘MyNewPassword’)
     -> WHERE User = ‘root’ AND Host = ‘localhost’;
     mysql> FLUSH PRIVILEGES;
     mysql> quit

  6. Stop mysql
     systemctl stop mysqld

  7. Unset the mySQL envitroment option so it starts normally next time
     systemctl unset-environment MYSQLD_OPTS

  8. Start mysql normally:
     systemctl start mysqld

  9. Try to login using your new password:
     mysql -u root -p

Reference

As it says at http://dev.mysql.com/doc/refman/5.7/en/mysqld-safe.html,

Note

As of MySQL 5.7.6, for MySQL installation using an RPM distribution, server startup and shutdown is managed by systemd on several Linux platforms. On these platforms, mysqld_safe is no longer installed because it is unnecessary. For more information, see Section 2.5.10, “Managing MySQL Server with systemd”.Which takes you to http://dev.mysql.com/doc/refman/5.7/en/server-management-using-systemd.html where it mentions the systemctl set-environment MYSQLD_OPTS= towards the bottom of the page

The password reset commands are at the bottom of
http://dev.mysql.com/doc/refman/5.7/en/resetting-permissions.html