model example
class Example(Stat):
numeric = models.IntegerField(...)
date = models.DateField( auto_now_add=True,...) #auto_now_add=True was the pro
It appears your problem is with there being more columns you're not including in your get_or_create
, see i.e. this thread on a Django mailing list.
You need to use the defaults
parameter of get_or_create
as described in the docs, or specify values for all columns, for get_or_create
to match correctly.