Why does Django Queryset say: TypeError: Complex aggregates require an alias? -


i have django class follows:

class mymodel(models.model):     my_int = models.integerfield(null=true, blank=true,)     created_ts = models.datetimefield(default=datetime.utcnow, editable=false)

when run following queryset, error:

>>> django.db.models import max, f, func >>> mymodel.objects.all().aggregate(max(func(f('created_ts'), function='unix_timestamp'))) traceback (most recent call last):   file "<console>", line 1, in <module>   file "myvirtualenv/lib/python2.7/site-packages/django/db/models/query.py", line 297, in aggregate     raise typeerror("complex aggregates require alias") typeerror: complex aggregates require alias

how adjust queryset don't error? want find instance of mymodel latest created_ts. , want use unix_timestamp function it.

i'm not running same django version, think this'll work:

mymodel.objects.all().aggregate(latest=max(func(f('created_ts'), function='unix_timestamp')))

note latest keyword argument in there. that's key (i think, again can't test this).


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