how to create file download link to a file stored in MYSQL database with PHP?

Question

I know I can just upload the file to a folder in my server, save the directory location to the MYSQL database, and create a download link based on that directory location but what happens when you store a file like a pdf or zip archive directly on the MYSQL database? How do you retrieve that data and create a file download link then?

Answer 1

You shouldn't store file data in your database, that's what the file system is for!

However to answer your question you would store the file contents in a BLOB field which contains the binary data, then to download throw the correct headers and echo the field value.

Answer 2

您可以创建一个类似“ download.php”的php文件，该文件将放置该文件类型（和大小）的标头，并回显所存储文件的内容。

Answer 3

You will have to set some content headers before outputting the data from your database, like:

header("Content-type: $type");
header("Content-length: $size");
header("Content-Disposition: attachment; filename=$name");
header("Content-Description: PHP Generated Data");
echo $data;

Full example at http://onlamp.com/pub/a/php/2000/09/15/php_mysql.html?page=3