RFC: Timestamps/timezones proposal

[Charles Day]

On Fri, Jul 18, 2008 at 9:01 AM, Charles Day <cedayiv at gmail.com> wrote:

> On Fri, Jul 18, 2008 at 3:46 AM, Graham Leggett <minfrin at sharp.fm> wrote:
>
>> Charles Day wrote:
>>
>>  ok, though what happens when the user decides to change the timezone for
>>>> account A? (eg. I ask the bank to transfer my account from their Saint
>>>> John's branch to their Vancouver branch, 5 timezones apart?) What
>>>> happens to
>>>> the timestamps and dates displayed then?
>>>>
>>>
>>> The timestamps don't change. Only the value displayed.
>>>
>>
>> This breaks double entry accounting.
>>
>> If account A and account B had different timezones, it means the balancing
>> splits within a transaction can fall on different days.
>>
>
> No, splits don't have posting dates or times. The entire transaction uses a
> single timestamp. That's how it works now. Under this proposal, that
> timestamp would only be *displayed* differently in different registers, or
> not, according to your preference.
>

(Actually, to be technically correct, each transaction has more than one
timestamp, but the others are for purposes other than recording when the
transaction was "posted".)


>
>
>>
>> If this happened over the start or end of a period of time, your accounts
>> would no longer balance - only half the split falls into the period!
>>
>> In order to be able to trust the data coming out of gnucash, gnucash must
>> be completely 100% and absolutely unambiguous about the data. If the user
>> specified a day, a month and a year, there must be absolutely no way
>> possible at all that circumstances can conspire to have that day month and
>> year changed to a different day month and year without the user's knowledge.
>> The single and only way a date should change is if the user explicitly went
>> in and changed that date, and at no other time.
>>
>
> I agree. What you experienced when you switched to the UK time zone is
> unacceptable.
>
>
>> The only safe way to do this is to store a date as a date, and not a
>> timestamp.
>>
>
> I disagree. If GnuCash uses timestamps, but a particular user such as
> yourself wants to disable the effects of time of day and time zone
> differences, then GnuCash could be set to use a single time zone for all
> accounts. I imagine there being a global preference called something like "I
> want to enter transaction times", which would be off by default, causing
> GnuCash to completely ignore the time zone of your computer, So when you
> moved your computer between time zones, it wouldn't affect your accounting.
>
>
>> Regards,
>> Graham
>> --
>>
>
> -Charles
>