Django Managers
- by owca
I have the following models code :
from django.db import models
from categories.models import Category
class MusicManager(models.Manager):
def get_query_set(self):
return super(MusicManager, self).get_query_set().filter(category='Music')
def count_music(self):
return self.all().count()
class SportManager(models.Manager):
def get_query_set(self):
return super(MusicManager, self).get_query_set().filter(category='Sport')
class Event(models.Model):
title = models.CharField(max_length=120)
category = models.ForeignKey(Category)
objects = models.Manager()
music = MusicManager()
sport = SportManager()
Now by registering MusicManager() and SportManager() I am able to call Event.music.all() and Event.sport.all() queries. But how can I create Event.music.count() ? Should I call self.all() in count_music() function of MusicManager to query only on elements with 'Music' category or do I still need to filter through them in search for category first ?
