title: Unique, unpredictable, 12 digit, integer id
body: <p>How would I go about generating this...  I want to keep my primary key sequential and have a 12 digit unique pin generated for each new object added to the database.</p>
  
  <p>The reason it cant just be autoincrement is i don't want the sequential numbers to be easily guessable.</p>
  
  <p>It needs to be integer numbers, because I'm going to have verification codes that need to be dialed on a phone pad.</p>