Question

I am working with django and having a hard time grasping how to do complex queries

Here is my model

class TankJournal(models.Model):     user = models.ForeignKey(User)     tank = models.ForeignKey(TankProfile)     ts = models.DateTimeField(auto_now=True)     title = models.CharField(max_length=50)     body = models.TextField()      class Meta:         ordering = ('-ts',)         get_latest_by = 'ts' 

I need to pull the username given the tank object.

The user object is the one built into django.. thanks!

EDIT:

I have tried this

print User.objects.filter(tankjournal__tank__exact=id) 

It seems to not pull out just the id.. and pull out everything in tankjournal and match it to the tank object

Answer 1

If you already have your tank object you should be able to do:

tank.user.username 

To reduce the database queries you might want to consider the use of select_related(), e.g.

tanks = TankJournal.objects.all().select_related() for tank in tanks:     username = tank.user.username 

if you have a specific tank id then:

tank = TankJournal.objects.select_related().get(id=123456) username = tank.user.username