Set Admin Password with MySQL (v5+)

UPDATE wp_users SET user_pass = MD5('"(NEWPASS)"') WHERE ID = (1);

Add admin user with MySQL (v5+)

INSERT INTO `wp_users` (`ID`, `user_login`, `user_pass`, `user_nicename`, `user_email`, `user_url`, `user_registered`, `user_activation_key`, `user_status`, `display_name`) VALUES ('2', 'admin2', MD5('demo'), 'Martin Test', 'test@yourdomain.com', 'http://dummy.com', '2014-06-07 00:00:00', '', '0', 'Martin Test');


INSERT INTO `wp_usermeta` (`umeta_id`, `user_id`, `meta_key`, `meta_value`) VALUES (NULL, '2', 'wp_capabilities', 'a:1:{s:13:"administrator";s:1:"1";}');


INSERT INTO `wp_usermeta` (`umeta_id`, `user_id`, `meta_key`, `meta_value`) VALUES (NULL, '2', 'wp_user_level', '10');