title: Why mysql_real_escape_string returns boolean?
body: <p>I have wrote a PHP script to handle user login. To prevent SQL Injection attack, I have used 'mysql_real_escape_string' function. Everything works good till today. I have traced code and finding the problem; the line using 'mysql_real_escape_string'. I have change it to basic command following:</p>
  
  <pre><code>$username=mysql_real_escape_string('sample');
  var_dump($username)
  </code></pre>
  
  <p>The output is:</p>
  
  <pre><code>bool(false)
  </code></pre>
  
  <p>On my local web server (WAMP) everything is ok, but on remote host the problem appears! What is wrong? (Host PHP is 5.4.12)</p>