regluit/test/querytests.py

40 lines
1.5 KiB
Python
Raw Normal View History

2013-06-03 16:31:39 +00:00
from itertools import izip
from django.db.models import Count
2013-06-03 16:31:39 +00:00
from regluit.core import models
def list_popular():
"""Compare calculating popular works using QuerySets + distinct() and order_by() with an alternate approach """
w1 = models.Work.objects.filter(wishlists__isnull=False). \
distinct().annotate(wished=Count('wishlists')).order_by('-wished', 'id')
# create a list of tuples of Works + the wishlist count, filter by non-zero wishlist counts, sort the list by descending
# number of wishlists + Work.id and then blot out the wishlist count
w0 = map (lambda x: x[0],
sorted(
filter(lambda x: x[1] > 0,
[(w, w.wishlists.count()) for w in models.Work.objects.all()]
) ,
key=lambda x: (-x[1],x[0].id)
)
)
print w1.count()
print len(w0)
print list(w1.all()) == w0
print "difference: ", filter(lambda item: item[1][0] != item[1][1], enumerate(izip(w0,w1)))
def list_new():
"""Compare calculating new works using QuerySets + distinct() and order_by() with an alternate approach """
w1 = models.Work.objects.filter(wishlists__isnull=False).distinct().order_by('-created', 'id')
w0 = [w for w in models.Work.objects.order_by('-created', 'id') if w.wishlists.count()]
print w1.count()
print len(w0)
print list(w1.all()) == w0
print "difference: ", filter(lambda item: item[1][0] != item[1][1], enumerate(izip(w0,w1)))