**Use case**

Like `date_time_input_format = 'best_effort'` but with disambiguation to American mm/dd/yyyy style.

UInt32 scale_, const TimezoneMixin & time_zone_)
    : SerializationDecimalBase<DateTime64>(DecimalUtils::max_precision<DateTime64>, scale_)
    , TimezoneMixin(time_zone_)
{
}
void SerializationDateTime64::serializeText(const IColumn & column, size_t row_num, WriteBuffer & ostr, const FormatSettings & settings) const
{
    auto value = assert_cast<const ColumnType &>(column).getData()[row_num];
    switch (settings.date_time_output_format)
    {
        case FormatSettings::DateTimeOutputFormat::Simple:
            writeDateTimeText(value, scale, ostr, time_zone);
            return;
        case FormatSettings::DateTimeOutputFormat::UnixTimestamp:
            writeDateTimeUnixTimestamp(value, scale, ostr);
            return;
        case FormatSettings::DateTimeOutputFormat::ISO:
            writeDateTimeTextISO(value, scale, ostr, utc_time_zone);
            return;
    }
}
void SerializationDateTime64::deserializeText(IColumn & column, ReadBuffer & istr, const FormatSettings & settings, bool whole) const