Thank you very much, now if I work. And besides I also served to enhance most of my consultations with dates. It is strange that I have not tried that way, if a large part of my consultations I had done that way, well, the important thing is that it works and I understand the reason. Thanks for the time spent and probably will call me here more often, either working or asking.
El martes, 1 de septiembre de 2015, 1:54:36 (UTC-4:30), James Schneider escribió: > > On Mon, Aug 31, 2015 at 5:37 PM, Serena <sereni...@gmail.com <javascript:>> > wrote: > > I understand what you say, when I started working with Django I thought > > exactly the same, it is more convenient that the date is saved with a > time > > zone and then the conversions are made, and also knew that the gap was > > precisely because those 4:30 in my timezone, but the problem is not to > show > > the data to the user, but as I make my queries so that the filtered data > is > > correct, since my dates are obvious questions, I'll put my concern > examples: > > > > The date does not place the customer, we do not control them. Each time > an > > invoice is added, the date placed in my controller using: > > >> factura = Factura() > > >> factura.fecha = timezone.now () > > >> factura.save () > > > > For example I consult my templates from sales day, and was shown to the > > customer in my template: > > 1. Add invoice number 6 on August 31, 2015 at 18:48 > > 2. Add Invoice Number 7 on August 31, 2015 at 18:48 > > 3. Add Invoice Number 8 on August 31, 2015 at 19:32 > > > > But Database I remain as follows: > > 1. Invoice number 6 Date: 08/31/2015 23:18:07 > > 2. Invoice number 6 Date: 08/31/2015 23:31:25 > > 3. Invoice number 6 Date: 01/09/2015 00:02:17 > > > > This helped my understanding immensely. Thank you. > > You know what is odd though, the DB entries for 2 and 3 seem to be > using a different format (MM/DD/YYYY and DD/MM/YYYY respectively). It > may be right if the data for 3 is really from January, though. > > > > > So if I want to consult the invoices (today August 31, 2015): > > > > >> Factura.objects.filter (fecha__startswith = timezone.now (). Date > ()) > > > > only leave me the invoice number 6 and number 7 because the number 8 > > corresponds to another day. > > > Ahh, there's the problem. You are performing a string match against > the beginning of the date string, not an actual comparison of dates > and times (ie is 04:00 later than 05:00, etc.). This is both slow, and > inaccurate, as you've experienced. Django will perform a numerical > comparison of the datetime's behind the scenes within the database, > which should yield faster and accurate results. > > > > > Is there any way of making the request and that django conversion made > > directly (with some function)? or I have to do the conversion? > > > > I hope I was more explicit. And much I appreciate your time. > > Django will do the hard stuff, but you need to feed it the right > information in order to do so. My understanding is that you want to > see all of the bills (class Factura) that have a date falling in > between 00:00 and 23:59 (a 24 hour period for 1 day) in your local > timezone (or more specifically, the default timezone of the server). > > I'm no timezone expert, but here is how I came up with performing the > query: > > import datetime > from django.utils import timezone > > # date today, default (server) timezone > d = timezone.localtime(timezone.now(), > timezone=timezone.get_default_timezone()).date() > > # grab the date, stripping away the current time > naive_start_date = datetime.datetime(d.year, d.month, d.day) > > # create a timezone aware datetime object with a time of 00:00 > (beginning of the day) by only providing the date > local_start_datetime = timezone.make_aware(naive_start_date, > timezone=timezone.get_default_timezone()) > > # create a timedelta object of 1 day > one_day = datetime.timedelta(days=1) > > # calculate 1 day in the future from the start datetime > local_end_datetime = local_start_datetime + one_day > > # query, use >= for start time since we start at 00:00 and < since > we use 00:00 of next day > bills = Factura.objects.filter(fecha__gte=local_start_datetime, > fecha__lt=local_end_datetime) > > > Most of this is just generating a date for the right > calendar/numerical day (based on the local timezone) and creating a > datetime for midnight (morning) of that day. The rest is pretty > simple. Hopefully this also accounts for DST and other timezone > anomalies beyond my comprehension. > > I would also highly recommend that you install the pytz module. Django > will use it if it is available, and will make your timezone handling > even more accurate. (See #3 > https://docs.djangoproject.com/en/1.8/topics/i18n/timezones/#faq ) > > Hopefully you can just copy/paste that into your shell and it'll come > up with the right results. Seems to work on my local machine. > Obviously if you want a different day you'll just need to come up with > a different naive_start_date. > > Well, I learned a lot answering your question, hope you do too, lol. > > -James > -- You received this message because you are subscribed to the Google Groups "Django users" group. To unsubscribe from this group and stop receiving emails from it, send an email to django-users+unsubscr...@googlegroups.com. To post to this group, send email to django-users@googlegroups.com. 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