public static function count($filter = []): int
    {
        /* @var $class LightModel */
        $className = get_called_class();
        $class = new $className;
        $tableKey = $class->getKeyName();

        $sql = 'SELECT COUNT(' . $tableKey . ') FROM ' . $class->getTableName() . ' WHERE 1=1';
        $params = self::handleFilter($sql, $filter, $class);

        $query = DB::getConnection()->prepare($sql);
        $query->execute($params);

        return (int) $query->fetchColumn(0);
    }