private function _check_time_column($column)
    {
        if (!static::table()->columnExists($column))
            return false;
        
        $type = static::table()->columnType($column);
        
        if ($type == 'datetime' || $type == 'timestamp')
            $time = date('Y-m-d H:i:s');
        elseif ($type == 'year')
            $time = date('Y');
        elseif ($type == 'date')
            $time = date('Y-m-d');
        elseif ($type == 'time')
            $time = date('H:i:s');
        else
            return false;
        
        $this->attributes[$column] = $time;
        
        return true;
    }