Re: Timetable updates [message #575 is a reply to message #574] |
Wed, 14 April 2004 09:29 |
Joachim.Rubröder
Messages: 33 Registered: September 2004
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I agree that a trainID like "4712" is not enough to identify a train.
For german DB we use a combination of line number, train number,
operating period and the timetable period as trainID and there are still
some identification problems to solve.
What abuot:
<trainID> technical ID to identify a train, used by the programs
(most often based on the train number)
<trainNumber> new element for the train number, as used by railways
like "4712"
<status> as suggested below, like "changed"
<date> with new ISO8601-format xsd:dateTime instead of
xsd:date (a date with optional time, fractional seconds up to
nanoseconds are possible like "19941105T08:15:00301")
best regards,
Joachim Rubröder
Tobias Bende schrieb:
> Thomas Kauer wrote:
>
>
>> In respect to possible future use of the timetable-schema as an interface
>> for programs that treat with actual trains and not only with longtime
>> planning it should support the possibility to give delta-informations for
>> existing timetable data. So it would be useful to add the proposed
>> attribute <status>.
>> The <date> of the last change would be used in this respect to decide for
>> multiple changes which one is the last, that is to say which one is valid.
>
>
>
> An example where one would definitely need delta-information is a
> day-of-operation system for railway companies. In such a system there
> would be several updates per second.
>
> It has to be asked if the <status> attribute is adequate for indicating
> changes. It could be if there existed some identity for each train, but an
> artificial identity (like train number + date) is not enough. For example,
> how would I send the information that train number 4711 is now called
> 4712?
>
>
>
>
>> Joachim Rubröder wrote:
>
>
>>> This case is not especially treated in the schema. But you are free to
>>> put a whole big timetable with thousand trains in a file, or to send
>>> just a few update-trains. I think this is a task for the receiving
>>> program to identify the trains as new or known ones.
>>
>
>>> There is the <date> attribute in <train> which could be used as date of
>>> the last change and I thought about adding another optional attribute
>>> <status> in the <train> element (as used within SBB) wich could have
>>> values like "new", "changed", "omitted", ...
>>> Would this be helpful?
>>
>
>>> Joachim Rubröder
>>
>
>>> Tobias Bende schrieb:
>>>
>>>> I have a question on updates of existing timetables. Given that a file
>>>> with a complete timetable (especially in a format like RailML) is very
>>>> large it is in practice often desirable to be able to send updates when
>>>> something changes as opposed to recreate and send the entire file. Is
>>>
> this
>
>>>> something that has been considered?
>>>>
>>>> Tobias Bende
>>>>
>>>>
>>>
>
>
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