获取范围内的所有月份和年份

Question

I am writing a django application where I have records stored on the basis of datetimefield.

        first_record = MyModel.objects.filter().order_by('-added').first()
        first_record = (first_record.added.month, first_record.added.year)
        last_record = MyModel.objects.filter().order_by('-added').first()
        last_record = (last_record.added.month, last_record.added.year)

Now I want to make a list of all months/year between the first record and last record. A rough idea is:

for i in range(first_record, last_record):
    # do something

Where the range function is supposed to give me a list to iterate over which looks like this:

[('01','2018'),('02','2018'),('03','2018'),....,('11','2020'),('12','2020')]

Any ideas how do I do that?

Also is (last_record.added.month, last_record.added.year) the right way to get a tuple containing month and year. Note that I want months in the format 01 instead of 1 for first month for example.

Answer 1

I believe Django has a built-in function. You can do:

>>> Entry.objects.dates('pub_date', 'month')
[datetime.date(2005, 2, 1), datetime.date(2005, 3, 1)]
>>> Entry.objects.dates('pub_date', 'week')
[datetime.date(2005, 2, 14), datetime.date(2005, 3, 14)]

Which, translated into your code, will be something like

MyModel.objects.dates('added', 'month')

Documentation

Answer 2

You can do this by using dateutil.relativedelta Here is the code

from dateutil.relativedelta import relativedelta
import datetime

result = []

today = datetime.date.today()
current = datetime.date(2010, 8, 1)    

while current <= today:
    result.append(current)
    current += relativedelta(months=1)

Know more abou in https://dateutil.readthedocs.io/en/latest/relativedelta.html