public static function sql($time = null): string
    {
        return self::factory($time)->format(self::SQL_FORMAT);
    }
public static function sql($time = null): string
    {
        return self::factory($time)->format(self::SQL_FORMAT);
    }
public static function sql ( $ time = null ) : string { return self :: factory ( $ time ) -> format ( self :: SQL_FORMAT ) ; }
Convert time for sql format

@param null|int $time
@return string
Convert time for sql format