On Tue, Feb 21, 2012 at 14:17, Yo-Yo Ma <baxterstock...@gmail.com> wrote: >[...] > When using UTC, which, if any, are true:
Not sure what you mean by "using UTC", I assume you mean "USE_TZ = True". As per first sentence of https://docs.djangoproject.com/en/dev/topics/i18n/timezones/ "When support for time zones is enabled, Django stores date and time information in UTC in the database, uses time zone-aware datetime objects internally, and translates them to the end user’s time zone in templates and forms." > A) If I have a view that simply adds a record of a model with a > datetime field, and 3 users in different timezones load the view at > the same time, all 3 records will have the same datetime value > (assuming, of course, the database was able to write all 3 records > within the same microsecond) They will have the same value in the database, yes. > B) UTC is *the* way to go for almost any application which will have a > timezone = models.CharField(... setting for each user profile See above - database will store everything in UTC. You could use a timezone field like that to store user timezone and activate it, e.g. through a middleware - https://docs.djangoproject.com/en/dev/topics/i18n/timezones/#selecting-the-current-time-zone NB: PostgrSQL already stores UTC internally - https://docs.djangoproject.com/en/dev/topics/i18n/timezones/#postgresql "The PostgreSQL backend stores datetimes as timestamp with time zone. In practice, this means it converts datetimes from the connection's time zone to UTC on storage, and from UTC to the connection's time zone on retrieval." For other backends that store naive datetimes "in UTC" means "assumed as being UTC". > C) When each user has a timezone setting, it doesn't affect the > datetime that's entered into the database, it just gives me the > ability to display the time to them in their timezone It doesn't affect the database. But it's up to you (middleware) to "activate" their timezone in order to make it the "current" timezone. If you don't do that, the "default" timezone (TIME_ZONE setting) will be the current timezone. Whatever a user enters in their "current" timezone is converted to UTC for storage - UTC is the only sane "common denominator". Cheers, Danny -- You received this message because you are subscribed to the Google Groups "Django developers" group. To post to this group, send email to django-developers@googlegroups.com. To unsubscribe from this group, send email to django-developers+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/django-developers?hl=en.
