Start database without permission checking:

service mysql stop
mysqld_safe --skip-grant-tables &

Set new password

mysql --user=root mysql
update user set Password=PASSWORD('new-password-here') WHERE User='root';
...
killall mysqld

Create file mysql-init with commands to execute at start.

service mysql stop
mysqld_safe --init-file=./mysql-init.sql &

GRANT LOCK TABLES ON *.* TO 'debian-sys-maint'@'localhost';

GRANT ALL PRIVILEGES ON *.* TO 'debian-sys-maint'@'localhost' GRANT RELOAD, SHUTDOWN, PROCESS, SHOW DATABASES, SUPER, LOCK TABLES ON *.* TO 'debian-sys-maint'@'localhost' IDENTIFIED BY PASSWORD 'xxxxxxxxxxxxxxxxxxxx' GRANT ALL ON testDB.* TO 'demo-user'@'localhost';

show databases; show tables;

SHOW GRANTS; SHOW GRANTS FOR CURRENT_USER; SHOW GRANTS FOR CURRENT_USER(); SELECT User,Host,Password FROM mysql.user; flush privileges;