Assuming someone is developing a site similiar to facebook in content where users are allowed to upload of heavy files, images, videos, pdf etc.
what could be the php best option of coding and fast in workability
1: Is it the best to upload and retrieve the files to and from directories
OR
2: Is it the best to upload and retrieve the files to and from the database (what about the database performance) and what are the reasons for choosing any of the 2 options
3: Assuming someone have a web hosting Hard disk space of 5mb and uploads a files of about 4mb to database. will the size of the hard disk be affected because of uploaded files in the database.unlike it will be affected when files is uploaded to a directory
4: Recovring heavy files from database OR from directory, which of them will be faster and scalable..
5: mysql database does it have a limited data it can contain or those it tends to infinity.
I am just paranoid and so i need codecall experts on these