A) You are using phpmyadmin.
B) The only way you would be able to directly upload a too-large file into a folder and import it using the host's supplied phpmyadmin is if your web host has configured the phpmyadmin $cfg['UploadDir'] setting to point to a per-user folder.
C) If your web host won't increase the upload_max_filesize and post_max_size settings where phpmyadmin is running and he hasn't or won't do item B), then your easiest solution would be break up the .sql files into multiple parts and upload/import each part separately.
D) You could always install phpmyadmin within your htdocs folder and use it to import your files. It would run under your php settings (where you should be able to set the upload_max_filesize and post_max_size settings) and your database connection credentials. In this case the $cfg['UploadDir'] setting could be set to a folder within your account and you could ftp the large file (or perhaps that's where it is already at) onto the server and import it.
E) Have you asked your web host to help with this. Perhaps he would import your too-large file for you using a different tool than phpmyadmin.
F) What sort of actual problem or error are you having?
If you are learning PHP, developing PHP code, or debugging PHP code, do yourself a favor and check your web server log for errors and/or turn on full PHP error reporting in php.ini or in a .htaccess file to get PHP to help you.