title: Make a value into NULL instead of empty in php
body: <p>I can't make the empty value to be checked as <em>NULL</em> in database instead of leaving an empty space when I am inserting a value.</p>
  
  <p>I don't want to leave an empty/blank space for an entry when it has no value.
  So if there is no file selected, make that entry into <em>NULL</em></p>
  
  <p>Is it unnecessary to be in <em>NULL</em>?</p>
  
  <pre><code>if (empty($_FILES['logo']['name'])) {
    $code = NULL;
    } else {
  }
  </code></pre>