The first things to check (or ask your host provider to check) are the values of upload_max_filesize, memory_limit and post_max_size in the php.ini configuration file. All of these three settings limit the maximum size of data that can be submitted and handled by PHP. One user also said that post_max_size and memory_limit need to be larger than upload_max_filesize. There exist several workarounds if your upload is too big or your hosting provider is unwilling to change the settings:
Look at the $cfg['UploadDir'] feature. This allows one to upload a file to the server via scp, ftp, or your favorite file transfer method. PhpMyAdmin is then able to import the files from the temporary directory. More information is available in the Configuration of this document.
Using a utility (such as BigDump) to split the files before uploading. We cannot support this or any third party applications, but are aware of users having success with it.
If you have shell (command line) access, use MySQL to import the files directly. You can do this by issuing the “source” command from within MySQL:
source filename.sql;