title: MySQL Transactions and how does Rollback work?
body: <p>I just came across Transactions and I wonder</p>
  
  <ol>
  <li>what are the pros and cons of using it,</li>
  <li>how does the rollback work, are the old values kept in memory, if bigger, what happens?</li>
  </ol>
  
  <p>For 1. I understand you have to use it for bank transfers, but would it not be better to use it for everything?!?</p>