Do you have a ready made script like your demo which allows from the broswer the upload/submit option but actually submits the data to the database.
The upload file will be a known format.
It's straight forward to handle file uploads in PHP, so an outline script whereby you have a file upload HTML form with which to upload and parse a file would be as follows:
// process record as normal e.g. insert into MySQL
<form enctype="multipart/form-data" method="POST">
Select File:<br />
<input name="userfile" type="file" />
<input type="submit" value="Upload" />
Replace xml|FORMAT/STRING/ with the actual format of your source data, and that should get you close!