Recently we had to import a db dump (.sql) file of size 346MB.
Yes there are tweaks to do the same via phpmyadmin to increase post limit, timeout time, upload size etc.
However doing it command line seemed like a better option
Here is the command to import the database
mysql -u your_user -p your_db_name < sql_filename.sql
This works irrespective of the dump size.
Cheers to command line!