How to use django annotate() and aggregate() to group a queryset?
I am trying to translate a sql query in django's ORM. Tried to use annotate() but I don't manage to get same results than the sql query.
This is my model :
class Fuel(models.Model):
type = models.CharField(max_length=150)
class Station(models.Model):
name = models.CharF开发者_如何转开发ield(max_length=150, null=True)
class Price(models.Model):
fuel_type = models.ForeignKey(Fuel)
station = models.ForeignKey(Station)
price = models.FloatField()
date = models.DateTimeField('Date', auto_now_add=True)
And this is the query I try to translate in django :
select * from myapp_price where id IN ((select max(id) from myapp_price where station_id=121600 group by fuel_type_id));
Is this possible ?
I get the expected results this way :
q=Price.objects.filter(station=filters['station_id']).values('fuel_type').annotate(Max('id')).values('id__max')
Price.objects.filter(pk__in=q)
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