presto-main/src/main/java/io/prestosql/type/TimestampWithTimeZoneOperators.java/TimestampWithTimeZoneOperators/subtract
class TimestampWithTimeZoneOperators:    @ScalarOperator(SUBTRACT)
    @SqlType(StandardTypes.INTERVAL_DAY_TO_SECOND)
    public static long subtract(@SqlType(StandardTypes.TIMESTAMP_WITH_TIME_ZONE) long left, @SqlType(StandardTypes.TIMESTAMP_WITH_TIME_ZONE) long right)
    {
        return unpackMillisUtc(left) - unpackMillisUtc(right);
    }