title: WP_Query with Custom Field Parameter (checkbox)
body: <p>I'm trying to set up a custom query that returns only posts that <strong>do not</strong> have a custom meta field checkbox is checked. The checkbox meta field id is <code>position-filled</code>.</p>
  
  <p>Here is the code I have:</p>
  
  <pre><code>$args = array (
      'post_type' =&gt; 'jobs',
      'posts_per_page' =&gt; 4,
      'post__not_in' =&gt; array(get_the_id()),
      'meta_query' =&gt; array(
          array(
              'key' =&gt; 'position-filled',
              'value' =&gt; 'on', // also tried passing null and removing 'compare'
              'compare' =&gt; '!=' // also tried 'NOT LIKE'
          )
      ),
  );
  $customQuery = new WP_Query($args);
  </code></pre>
  
  <p>However, this returns no posts (I have made certain there are posts <strong>without</strong> the checkbox checked.</p>
  
  <p>Any idea what I'm doing wrong?</p>