django/python - db hits while accessing variables -

class appuser(models.model):     user = models.foreignkey(user, unique=true)     slug = models.slugfield(editable=false, blank=true)

for above model suppose have object "appuser" have rendered in template

does django hits user db each time when use appuser.user.username in our code??

any on how in django/python db lookups done while accessing foreign key , many-to-many variables ??

you should read through details database access optimization: https://docs.djangoproject.com/en/1.3/topics/db/optimization/

and select_related():

as quick answer question: depends on how you've retrieved object

with

appuser = appuser.objects.get(pk=id)

it hit database separately appuser.user.

but with

appuser = appuser.objects.select_related().get(pk=id)

it joined query, accessing appuser.user not trigger sql query.

Barbera