title: VARCHARS: 2, 4, 8, 16, etc.? Or 1, 3, 7, 15, etc.?
body: <p>I see VARCHAR(255) being used all the time instead of VARCHAR(256), but I also see VARCHAR(16) being used instead of VARCHAR(15). This seems inconsistent to me. If an extra byte is being used to store the VARCHAR's length, shouldn't this rule also apply to the smaller lengths like 2, 4, 8 to be 1, 3, 7, instead?</p>
  
  <p>Or am I totally missing something?</p>
  
  <p>In other words, if I have a number that I know will never be above 12, should I just go ahead and use a VARCHAR(15) or VARCHAR(16) instead? Because it uses the same amount of space as a VARCHAR(12)? If so, which one do I use? 15 or 16? Does this rule change at all when I get closer to 256?</p>
  
  <p>I use both MySQL and SQL, depending on the project.</p>