I'm a bit confused by this, so hopefully I can get some clarification.
A int, by default, is 11 characters long. When an entry is created with an int column, does the db set aside space for an 11 character number, even if I set the length to 2 (I know, tinyint). Basically, if I have something like a tinyint at 2, does it save space? or does it just limit what can be entered, which I'm already restricting in PHP.