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Django, can I get the reference objects included in the query set

Let's say I have these models:

models.py:

class Item(models.Model):
    ref_id = models.PositiveIntegerField()
    name = models.CharacterField(max_length=32)

class ItemDue(models.Model):
    item = models.ForeignKey(Item)
    due_date = models.DateField(null=True, blank=True)
    lots of other fields below
    .
    .
    .

I want to request objects ItemDue, but I also want to include Itemwith the request.

If I get the kit ItemDue, I can loop like this:

for item_due in ItemDue.objects.filter(some_criteria):
    print item_due.item.ref_id

, , , Item, ItemDue, Item.ref_id. , Item.ref_id , ItemDue s. .values('id', 'item__ref_id'), ItemDue id item__ref_id. , .values('id', 'item__ref_id', ...) ItemDue, . ItemDue item__ref_id?

EDIT:

manage.py:

def check():
    start = datetime.now()
    print "Starting {0}".format(datetime.now() - start)
    index = 0
    item_rows = dict()
    print "Getting Items for PG and Parents {0}".format(datetime.now() - start)

    # items due for PG
    items = pg.item_due.all().filter(disabled=False).select_related()

    # Loop the parents, and chain their items due to the PG items due.
    for p in parents:
        items = itertools.chain(items, p.item_due.all().filter(disabled=False).select_related())
        index += 1
    print "All Items Retrieved {0}".format(datetime.now() - start)
    for item in items:
        pass
    print "Loop Items Complete {0}".format(datetime.now() - start)
    return item_rows

>>> rows = check()
Starting 0:00:00.000008
Getting Items for PG and Parents 0:00:00.000032
All Items Retrieved 0:00:00.004669
Loop Items Complete 0:00:00.022597

, , pass 0,01 .

pass item.item.ref_id, LOT .

def check():
    start = datetime.now()
    print "Starting {0}".format(datetime.now() - start)
    index = 0
    item_rows = dict()
    print "Getting Items for PG and Parents {0}".format(datetime.now() - start)

    # items due for PG
    items = pg.item_due.all().filter(disabled=False).select_related()

    # Loop the parents, and chain their items due to the PG items due.
    for p in parents:
        items = itertools.chain(items, p.item_due.all().filter(disabled=False).select_related())
        index += 1
    print "All Items Retrieved {0}".format(datetime.now() - start)
    for item in items:
        item.item.ref_id
    print "Loop Items Complete {0}".format(datetime.now() - start)
    return item_rows

>>> rows = check()
Starting 0:00:00.000007
Getting Items for PG and Parents 0:00:00.000031
All Items Retrieved 0:00:00.004712
Loop Items Complete 0:00:00.258209

0,018 0,25 . 13 item.item.ref_id, ?

+4
1

select_related, :

for item_due in ItemDue.objects.filter(some_criteria).select_related():
    print item_due.item.ref_id
+6

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