title: varchar() primary key or int primary key?
body: <p>I have a problem with MySql primary keys, it's for my project i'm working on now!</p>
  
  <p>i have to have a unit name(not a number)as a key in my database, it is a combination of letters and numbers, i can't use any primary key in INT type, where it increments as usual!</p>
  
  <p>what is better? should i stick to old INT, auto increment way? </p>
  
  <p>or it's better to use a VARCHAR to primary key? if so what is the ideal data type?</p>
  
  <p>regards,
  Rangana </p>