title: How to choose database management system?
body: <p><strong>Basic requirements</strong></p>
  
  <ol>
  <li>Fault tolerant (ex. has to work even when an entire data center goes down)</li>
  <li>Maximum number of records are about 1-5 billion</li>
  <li>Has to work properly and comparatively fast under high load</li>
  <li>Compatible with JavaEE</li>
  <li>Prefer relative DB but in general it doesn't matter</li>
  <li>Free of charge</li>
  </ol>
  
  <p>Do you have any ideas?</p>