If you are having issues to import large SQL files, one possible solution is BiGDump script. However, accessing the server through ssh and using mysql command to import/restore will work as well (and the better solution).
I just tried BigDump - it worked pretty well for me. The idea is simple: you download the zip, unzip and you will see only one file bigdump.php. Open the file and change some configurations such as database credentials and sql file name (sql file to import). You can access this file from web and upload the sql file as well (though max file size limit 64MB when you use web-ui to upload file). Upload the bigdump.php file to the server. access the file from the web and click on start import. you will be shown the progress and statistics.
(if you already configured filename in the bigdump.php, you will not see the options to upload the file again i.e. when you access bigdump.php from web)
Though accessing the server using ssh and using mysql command to restore is the better option. I tried bigdump.php anyway - to test the script. And in practice, you might not have ssh access or you might be having issues with your ssh access - in these cases bigdump.php can be of help. But delete the bigdata.php file from your server, once you are done.
"Staggered import of large and very large MySQL Dumps (like phpMyAdmin dumps) even through the web servers with hard runtime limit and those in safe mode. The script imports only a small part of the huge dump and restarts itself. The next session starts where the last was stopped."
Download Link: http://www.ozerov.de/bigdump.zip