Long long time ago, I created a poll on a small website I was maintaining. I didn't expect much traffic and, so, not thinking too much about it, I put the ID co

Long long time ago, I created a poll on a small website I was maintaining. I didn't expect much traffic and, so, not thinking too much about it, I put the ID column to be a TINYINT (i.e. max value = 255)... That was a valuable lesson. (I actually generated most entries myself while testing stuff - live in prod of course - and while there were probably fewer than 255 votes, the AUTO_INCREMENT did its job and produced an overflow).