public static function filter_month(\System\Database\Query $query, $val)
{
$date = new \DateTime($val);
$date->modify('midnight');
$start = clone $date;
$end = clone $date;
$start->modify('first day of this month');
$end->modify('last day of this month')->modify('tomorrow');
$conds = array("start >= '" . $start->format('Y-m-d H:i:s') . "'", "start < '" . $end->format('Y-m-d H:i:s') . "'");
return $query->where($conds);
}
