If you want to import / restore MYSQL database backup using phpMyAdmin just follow the below steps,

By default file import size is 128MB in XAMPP latest version, you need to increase?.

Step 1 : Open your phpMyAdmin on browser and click on "Import" Icon, can see the import file size is (Max 128MiB)

 Probably  need to make two changes in php.ini configure file. 

Step 2 :  Open your php.ini file from the XAMPP by any text editor (vim, vi, gedit and etc), file location is  /opt/lampp/etc

# vim /opt/lampp/etc/php.ini

Need to find and modify the configurations, post_max_size & upload_max_filesize.




Step 3 : Once you have modified in php.ini file restart your XAMPP and refresh that same page on browser.

# /opt/lampp/lampp restart
Restarting XAMPP for Linux 1.8.3-4...
XAMPP: Stopping Apache...ok.
XAMPP: Stopping MySQL...ok.
XAMPP: Stopping ProFTPD...ok.
XAMPP: Starting Apache...ok.
XAMPP: Starting MySQL...ok. 

Note : This chnages also acceptable in Windows and restart your XAMPP.