Tag error: <txp:smd_query query='SELECT COUNT(*) AS count
  FROM jvg_booking
  WHERE article_id = <txp:article_id />
  AND canceled = 0
  AND deleted = 0'>

  <txp:variable name="booked" value='{count}' />
  <txp:variable name="capacity" value='<txp:custom_field name="capacity" />' />
  <txp:variable name="color" value="green" />
  <txp:variable name="denomination" value="plaatsen" />
  <txp:variable name="unbooked" value='<txp:custom_field name="capacity" />' />

  <txp:php>
  // import txp variables into php scope
  $booked = variable(array('name' => 'booked'));
  $capacity = variable(array('name' => 'capacity'));
  $color = variable(array('name' => 'color'));
  $denomination = variable(array('name' => 'denomination'));

  // only start calculating with valid integers
  if (((is_int($booked)   || ctype_digit($booked))   && (int)$booked >= 0) &&
      ((is_int($capacity) || ctype_digit($capacity)) && (int)$capacity > 0)) {

    $unbooked = $capacity - $booked;
    if ($unbooked < 0) { $unbooked = 0; }

    $progress = ($booked / $capacity) * 100;
    if ($progress < 60) {
      $color = 'green';
    } elseif ($progress < 100) {
      $color = 'orange';
    } else {
      $color = 'red';
    }

    $denomination = $unbooked === 1 ? 'plaats' : 'plaatsen';

    // export php variables to txp scope
    variable(array('name' => 'capacity', 'value' => $capacity));
    variable(array('name' => 'color', 'value' => $color));
    variable(array('name' => 'denomination', 'value' => $denomination));
    variable(array('name' => 'unbooked', 'value' => $unbooked));
  }
  </txp:php>

  <txp:if_variable name="unbooked" value="0">
    <div class="button <txp:variable name='color' />">
      <p><strong>Er zijn geen plaatsen meer
      beschikbaar.</strong></p>
    </div>
      <p class="button appendix">Geef je toch op, we
      mailen je als er een plaats beschikbaar komt.</p>
  <txp:else />
    <div class="button <txp:variable name='color' />">
      <p><strong>Nog
      <txp:variable name="unbooked" />
      <txp:variable name="denomination" />
      beschikbaar van
      <txp:variable name="capacity" />.
      </strong></p>
    </div>
  </txp:if_variable>
</txp:smd_query> ->  Textpattern Notice: smd_query tag is not registered while parsing form jvg_booking_status on page cursussen

textpattern/lib/txplib_publish.php:557 trigger_error()
textpattern/lib/txplib_publish.php:466 processTags()
textpattern/lib/txplib_misc.php:4407 parse()
textpattern/publish/taghandlers.php:569 parse_form()
output_form()
textpattern/vendors/Textpattern/Tag/Registry.php:116 call_user_func()
textpattern/lib/txplib_publish.php:542 Textpattern\Tag\Registry->process()
textpattern/lib/txplib_publish.php:466 processTags()
textpattern/publish/taghandlers.php:2994 parse()
excerpt()