I can't think of the specifics, but I think I know what you are talking about.
Unless some MySQL guru cares to step in and tell me "Why storing Avatars in MySQL is no big deal", conventional wisdom stills tells me, "Not a good idea."
FWIW, this topic started as follows...
I let people upload an Image for their Profile Pic/Avatar, but my code only allows one occurrence of any given Image File. (The only thing worse than one person using Miley Cyrus as their Avatar, is 500 people doing it. Yuck!!)
To stop everyone from doing that, my script uses the function hash_file() to take "Debbie At Beach.jpeg" and convert it to "98543890918.jpeg", then store the renamed file to the "uploads" directory while also storing the new name into the Member's record in the "member" table.
The problem is that if I upload a new photo, "Debbie At Mall.jpeg" then the original file is getting left behind?!
There is a PHP function called unlink() which deletes files, but I see that as a major security risk - especially since it would be in my "upload.php" script which is outward facing.
So it was suggested that if I store the Images in the database, then I have extra security, and less fears of some hacker deleting every Image on my website!!
Likely a true point, BUT is it worth the extra coding and Database strain??
From what I have heard over the years, this wouldn't be a first choice...[/ot]