Re: Inserting Calendar.Time in a database

[Jano <nono@celes.unizar.es>]

Martin Dowie dice...
> Dmitry A. Kazakov wrote:
> >> I need to insert some timestamps (type Ada.Calendar.Time) in a
> >> database accessed via ODBC using gnade+gnat 3.15p.
> >>
> >> I've looked for timestamp support in the gnade sources without much
> >> luck, I've specially checked the embedded sql support and I haven't
> >> found nothing for this purpose.
> >>
> >> I'm completely clueless about the ODBC client packages so if someone
> >> has done this before (with gesql or directly), a quick pointer for
> >> the things to look at would be great.
> >
> > The problem is that Ada.Calendar.Time is a political time, while
> > persistent time stamps should be UTC or any other absolute time. I
> > know no OS-independent solution for that.
> 
> Ada.Calendar.Time_Zones might be of use to you. You could store
> the value as a string (Ada.Calendar.Formatting).

I hadn't thought of time zones and you both are probably right in your 
concern, but for now this is a secondary worry. This is for local and 
non-critical use. I simply want to have a timestamp in the database 
starting from an Ada time type...

Currently I'm doing something similar to the Martin suggestion: instead 
of storing a formatted string, I'm storing the seconds elapsed since an 
arbitrary epoch.

This is a bit clumsy since I can't work with dates if I want to keep the 
queries indexed. I think I'll move to a two-column-with-trigger-on-
insertion setup if no better solution is found.

Thanks!