问题
This issue has been occurring on and off for a few weeks now, and it's unlike any that has come up with my project.
Two of the models that are used have a timestamp field, which is by default set to timezone.now()
.
This is the sequence that raises error flags:
Model one is created at time 7:30 PM
Model two is created at time 10:00 PM, but in the MySQL database it's stored as 7:30 PM!
Every model that is created has its time stamp saved under 7:30 PM, not the actual time, until a certain duration passes. Then a new time is set and all the following models have that new time... Bizzare
Some extra details which may help in discovering the issue:
I have a bunch of methods that I use to strip my timezones of their tzinfo
's and replace them with UTC.
This is because I'm doing a timezone.now() - creationTime
calculation to create a: "model was posted this long ago" feature
in the project. However, this really should not be the cause of the problem.
I don't think using datetime.datetime.now()
will make any difference either.
Anyway, thanks for the help!
回答1:
Just ran into this last week for a field that had default=date.today()
. If you remove the parentheses (in this case, try default=timezone.now
) then you're passing a callable to the model and it will be called each time a new instance is saved. With the parentheses, it's only being called once when models.py
loads.
回答2:
Just set the parameter auto_now_add
like this.
timestamp = models.DateTimeField(auto_now_add=True)
Update:
Please don't use auto_now_add
. It is not the recommended way, instead do this:
from django.utils import timezone
timestamp = models.DateTimeField(default=timezone.now)
来源:https://stackoverflow.com/questions/13225890/django-default-timezone-now-saves-records-using-old-time