Plesk: how to get root password for MySQL
first there is no root mysql account with plesk . when plesk is installed it rename root MYSQL account to admin.
for plesk 8.x and 9.x password are store it /etc/psa/.psa.shadow use this command to get password
# cat /etc/psa/.psa.shadow
in these latest version plesk 10.x admin password store it /etc/psa/.psa.shadow are highly encrypted so to view password use this command
# /usr/local/psa/bin/admin --show-password # on Linux "%plesk_bin%\plesksrvclient" -get # on Windows
also to login to mysql with root privileges use the following command
cat /etc/psa/.psa.shadowmysql -u admin # on Linux "%plesk_dir%\MySQL\bin\mysql" -P8306 -uadmin -p<password_from_the_previous_step> YOUR_DATABASE_NAME # on Windows