title: Do I need a "random salt" once per password or only once per database?
body: <p>Further to <a href="https://stackoverflow.com/questions/2998999/can-someone-point-me-to-a-good-php-mysql-salted-hashed-password-implementation">my previous question about salted passwords in PHP/MySQL</a>, I have another question regarding salts.</p>
  
  <p>When someone says "use a random salt" to pre/append to a password, does this mean:</p>
  
  <ul>
  <li><strong>Creating a static a 1 time randomly generated string of characters</strong>, <em>or</em> </li>
  <li><strong>Creating a string of characters that changes at random every time a
  password is created</strong>?</li>
  </ul>
  
  <p>If the salt is random for every user and stored along with the hashed password, how is the original salt ever retrieved back for verification?</p>