Its due to PHP that has a file size restriction for uploads.
If you have terminal/shell access then the above answers @Kyotoweb will work.
one way to get it done is that you create an .htaccess/ini file file to change PHP settings to get the sql file uploaded through PHPmyAdmin.
php_value upload_max_filesize 120M //file size
php_value post_max_size 120M
php_value max_execution_time 200
php_value max_input_time 200
Note you should remove this file after upload.