How to download the file uploaded to a BLOB field using PhpMyAdmin? - php

Question

I'm running a localhost mysql server with PhpMyAdmin version 4.2. I created a table with a MEDIUMBLOB column to store file. I can upload *.doc files correctly, but when I click the file link, it downloads it as a "tablename-columnname.bin" bin file.
Then I tried to manually rename this "tablename-columnname.bin" to "original_file.doc" and the doc can be opened correctly.
Question: Why phpmyadmin does not download the file as is? What can I do to fix it? I know a bit of php
Thanks!

Answer 1

Use the 'header' before echo the file
header('Content-type: application/msword');
for dynamic way to find the 'Content type' use to store the 'file name' with 'extension' in database.

Answer 2

To make it a bit dynamic (based on MIME) I did the following change:
In tbl_get_field.php file, last few lines:
$mime = PMA_detectMIME($result);
switch($mime){
case 'image/jpeg':
$extension = 'jpg';
case 'image/gif':
$extension = 'gif';
case 'image/png':
$extension = 'png';
case 'application/pdf':
$extension = 'pdf';
default:
$extension = 'bin';
}
PMA_downloadHeader(
$table . '-' . $_GET['transform_key'] . '.' . $extension,
$mime,
strlen($result)
);
echo $result;
Code above should output the file with correct extension instead of always ".bin".
In mime.lib.php file, we need to detect more MIME cases:
function PMA_detectMIME(&$test)
{
$len = strlen($test);
if ($len >= 2 && $test[0] == chr(0xff) && $test[1] == chr(0xd8)) {
return 'image/jpeg';
}
if ($len >= 3 && substr($test, 0, 3) == 'GIF') {
return 'image/gif';
}
if ($len >= 4 && substr($test, 0, 4) == "\x89PNG") {
return 'image/png';
}
return 'application/octet-stream';
}
I want to add pdf and word doc in this, but I dont know how to determine their MIME type base on the stream characters