title: What is a database prefix in web applications?
body: <p>Currently I am working with search engine optimization.</p>
  
  <p>I have a problem with db, i.e.: </p>
  
  <pre><code>define('PHPDIG_DB_PREFIX','&lt;dbprefix&gt;'); 
  </code></pre>
  
  <p>I know the db name, host name, password. But in an open source they are mentiong that <code>PREFIX</code> line.</p>
  
  <p>I'm just confused. What should I use for prefix?</p>
  
  <p>Thanks.</p>