price.date, transaction.post_date and neutral time

[Wm]

On 12/02/2018 21:00, Sébastien de Menten wrote:
> When I enter a new price for a given day for a security on the NASDAQ via
> the price editor, it is stored in the date column the UTC time for that day
> at 00:00:00 local time (CET=Europe, not EST=New-York). Which is weird
> because across timezone, the day of the price will be interpreted
> differently.

Are you entering the prices by hand ?

> But John R says "that's an absolute time anchored in the market's time
> zone, not the user's. " which leaves me puzzled as for the example above on
> the NASDAQ it uses European time (i.e.my local time) not NASDAQ time. But
> maybe when using the Perl finance quote program, there is a more complete
> time information (incl the correct market timezone).

If you are entering the prices yourself then it seems sensible to me the 
time is when you made the entry rather than the market's time.

Also, unless you have a special arrangement with a broker, most people 
don't get a market price, it will be a bit under or over so the market 
price is just for reference once you include tx costs, etc.

> Anyway, my question was to understand the reasons of the encoding of a
> day/date as an instant/datetime, reasons that are still a bit obscure
> (except legacy issue)

For most purposes it shouldn't matter.  The prices db is independent of 
the actual transactions, it is used for working out the value of stuff 
and, as I am sure you are aware, the value of commodities changes every 
minute and second ... gnc is *never* going to keep up with that sort of 
price change.

In retrospect it may be thought that the design mistake was including a 
time in the price db at all :)

-- 
Wm