presto-main/src/main/java/io/prestosql/operator/scalar/DateTimeFunctions.java/DateTimeFunctions/dayOfWeekFromTimestampWithTimeZone
class DateTimeFunctions:    @Description("day of the week of the given timestamp")
    @ScalarFunction(value = "day_of_week", alias = "dow")
    @SqlType(StandardTypes.BIGINT)
    public static long dayOfWeekFromTimestampWithTimeZone(@SqlType(StandardTypes.TIMESTAMP_WITH_TIME_ZONE) long timestampWithTimeZone)
    {
        return unpackChronology(timestampWithTimeZone).dayOfWeek().get(unpackMillisUtc(timestampWithTimeZone));
    }