SET PASSWORD FOR 'jeffrey'@'localhost' = PASSWORD('mypass');

Or

ALTER USER user IDENTIFIED BY 'auth_string';

Reset Root:

Stop the MySQL service

(Ubuntu and Debian) Run the following command:

sudo /etc/init.d/mysql stop

(CentOS, Fedora, and Red Hat Enterprise Linux) Run the following command:

sudo /etc/init.d/mysqld stop

Start MySQL without a password

Run the following command. The ampersand (&) at the end of the command is required.

sudo mysqld_safe --skip-grant-tables &

Connect to MySQL

Run the following command:

mysql -uroot

Set a new MySQL root password

Run the following command:

use mysql;update user set password=PASSWORD("mynewpassword") where User='root';flush privileges;quit

Stop and start the MySQL service

(Ubuntu and Debian) Run the following commands:

sudo /etc/init.d/mysql stop...sudo /etc/init.d/mysql start

(CentOS, Fedora, and Red Hat Enterprise Linux) Run the following commands:

sudo /etc/init.d/mysqld stop...sudo /etc/init.d/mysqld start

Log in to the database

Test the new password by logging in to the database.

mysql -u root -p

You are prompted for your new password.