How to Count quantity of my QuerySet. Django-CodePudding

Well, i have the following function:

employees_birthday = Employees.objects.filter(EmployeeDataNasc__gte=first_day, EmployeeDataNasc__lte=last_day)

It serves to return employees born between the dates. She returns:

<QuerySet [<Employees: Alberto Santos>, <Employees: Josney Arman>]>

But, I would just like to display the number of employees in the QuerySet, i.e. make a Count function.

Can someone help me with the syntax?

CodePudding user response：

You can use the .count() method on a queryset to get the number of items in the queryset. Here's the updated code:

employees_birthday = Employees.objects.filter(EmployeeDataNasc__gte=first_day, EmployeeDataNasc__lte=last_day)

employee_count = employees_birthday.count()

In this example, employees_birthday is the queryset containing all employees born between the given dates. The .count() method returns the number of items in the queryset, which is stored in the variable employee_count.

You can then use the employee_count variable in your code to display the number of employees, for example:

print("Number of employees born between {} and {}: {}".format(first_day, last_day, employee_count))

CodePudding user response：

If you are going to display the Employees anyway, then it is better to use len(…). This will fetch the Employees in memory, and return the number of Employees:

employees_birthday = Employees.objects.filter(
    EmployeeDataNasc__range=(first_day, last_day)
)
number_of_birthdays = len(employee_birthdays)

if you however plan to only render the number of Employees, then you use .count() ^[Django-doc], since this will prevent fetching the items in memory.