Create plain text password:

root@host [~]# head -c 23 /dev/urandom | base64 | tr -d '/+=' | cut -c1-23 wAXMRV05x8iMaAoW5BsNewa

Enter mysql:

mysql -u yourmysqluser -p

or

mysql -uroot -p

mysql>

show databases;

mysql>

use yourdatabse;

wp_users is the default table name for the users

mysql>

select ID,user_login,user_pass from wp_users;

it will show the user list

mysql>

update wp_users set user_pass = MD5('wAXMRV05x8iMaAoW5BsNewa') where ID = 3;

ID = 3 is an example