querying in django
I have stored data in the table with respect to dates ie there could be more than one entry for the same month, but when i retrieve them i need to get them as combined result. So is there anyway that i could query it to retrieve the data for a month that is set the range as month in django(view).
edit:
Modifications from my prev post. I need to do it for a year and i do not have a specific start date and end date. I need to set the range for months in a year irrespective of the number of days present. my database would loo开发者_如何学运维k like this:
date count1 count2
2011/12/01, 12, 3
2011/12/03, 3, 6
Now i need to retrieve count1 for the month of december. I need a generic query not just for a particular month with say 30 or 31 or 28 days.
docs
Assuming you have a DateField
class MyModel(models.Model):
my_date = models.DateField()
query:
import datetime
startdate = datetime.date(...start of some month...)
enddate = datetime.date(...end of some month...)
my_model_in_range = MyModel.objects.filter(my_date__range(startdate,enddate))
edit:
count docs
import datetime
def first_day_of_month(month, year):
return datetime.date(year, month, 1)
def last_day_of_month(month, year):
return datetime.date(year, month+1, d.day) - datetime.timedelta(1)
# if you want query for jan 2009: month = 1, year = 2009
first = first_day_of_month(1, 2009)
last = last_day_of_month(1, 2009)
objects_in_jan_2009 = MyModel.objects.filter(my_date__range(first, last))
count = objects_in_jan_2009.count()
After you receive you range, query you model with the following:
YouModel.objects.filter(date__gt='initial date').filter(date__lt='final date')
date should be a field in your model. the __gt and __lt aply a filter for the field to search for values greater and lesser than the parameter passed.
Best way to do it is through raw sql
YourModel.objects.extra( select={'values':'select sum(count) as count , extract(month from mymodel_db.date) as date group by date'}
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