Reset MySQL root password :

Do so:

service mysql stop

wait until MySQL shuts down. Then run

mysqld_safe --skip-grant-tables &

then you will be able to login as root with no password.

mysql -uroot mysql

In MySQL command line prompt issue the following command:

UPDATE user SET password=PASSWORD("abcd") WHERE user="root";
FLUSH PRIVILEGES;

At this time your root password is reset to "abcd" and MySQL will now
know the privileges and you'll be able to login with your new password:

mysql -uroot -pabcd mysql

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