'FROM notice LEFT JOIN notice_to_status ' .
'ON notice.id = notice_to_status.notice_id ' .
'WHERE notice.source = "twitter"' .
- 'AND notice_to_status.status_id = NULL');
+ 'AND notice_to_status.status_id IS NULL');
while ($n->fetch()) {
if (preg_match('#^http://twitter.com/[\w_.]+/status/(\d+)$#', $n->uri, $match)) {