将图像替换为服务器中的其他图像

For examples, You can upload profile avatar to your profile. I want to remove the previous one the user had.

So before the query, where it changes the column "avatar" with the newfile2.jpg i would like to get the old file newfile1.jpg, and remove the previous image from the server.

How can I remove an image from the server?

You could just use a naming convention. Something like:

<user_id>_avatar.jpg

so when the user uploads the new avatar image it just overwrites the old one.

Well i truly agree with the "Phill", you can use the naming conventions, But you really want to delete then use the unlink command.

$filename = // File name with full path
unlink($filename);

Thanks