mysqlimport -L -h HOSTNAME -u USER -p PASSWORD DATABASE DUMPED_TEXTFILE
HOSTNAME is the hostname that you set up in your control panel for the database, mysql.domain.com or somesuch
USER is the username you've set up in your control panel
PASSWORD is the password you've assigned to the above user in your control panel
DATABASE is the name of the database you created in the control panel
DUMPED_TEXTFILE the name of the text file you've uploaded and are trying to import, "example.sql" for our purposes here
To make things easy you should upload the sql file to your user root since that's where you'll be when you login via shell. To draw a picture, fire up the ftp and the user root should have some files and folders in it like:
/yourdomain.com
/logs
/Maildir
.bashrc
etc etc etc... you should upload the "example.sql" file right into that spot. When done there, login to the shell and type the example line with the proper bits filled in and hit enter, that should do it...
mysqlimport -L -h mysql.domain.com -u myusername -p mypassword mydatabase example.sql
jason