title: How to retrieve spam comments in drupal DB to delete them using SQL?
body: <p>I want to retrieve all spam comments in my Drupal DB to remove them using SQL <code>DELETE</code> statement. <br>
  I cannot find how comments are marked  as spams in Drupal DB's <code>comment</code> table. <br>
  The only relevant column in <code>comment</code> table is <code>status</code>, which takes value 0 when the comment is unpublished. <br>
  But the unpublished comment can be either a legitimate comment (i.e. not yet approved), or a spam comment. <br></p>
  
  <p><strong>So, how to retrieve all spam comments by SQL to delete them from comments table ?</strong> </p>