prepare("SELECT related_request_no FROM change_requests WHERE related_request_no LIKE ? ORDER BY related_request_no DESC LIMIT 1"); $stmt->execute([$prefix . '%']); $lastRequest = $stmt->fetch(); $running_no = 1; if ($lastRequest) { $last_no = (int)substr($lastRequest['related_request_no'], strlen($prefix)); $running_no = $last_no + 1; } $related_request_no = $prefix . str_pad($running_no, 3, '0', STR_PAD_LEFT); ?>