我有一个模型Post和一个模型Vote。投票(形式为django-voting)实质上只是指向Post和-1、0或1的指针。
还有Tourn,它是开始日期和结束日期。在Tourn的开始和结束之间创建的帖子将提交给该锦标赛。
为了进行代表计算,我试图找到比赛的前3名获胜者。这就是我所拥有的:
posts = Post.objects.filter(status=2, created_at__range=(tourn.start_date, tourn.end_date))
start = tourn.start_date - timedelta(days=1)
end = tourn.end_date + timedelta(days=1)
qn = connection.ops.quote_name
ctype = ContentType.objects.get_for_model(Post)
posts.extra(select={'score': """
SELECT SUM(vote)
FROM %s
WHERE content_type_id = %s
AND object_id = %s.id
AND voted_at > DATE(%s)
AND voted_at < DATE(%s)
""" % (qn(Vote._meta.db_table), ctype.id, qn(Post._meta.db_table), start, end)},
order_by=['-score'])
if tourn.limit_to_category:
posts.filter(category=tourn.category)
if len(posts) >= 1:
tourn_winners_1.append(posts[0].author)
resp += " 1: " + posts[0].author.username + "\n"
if len(posts) >= 2:
tourn_winners_2.append(posts[1].author)
resp += " 2: " + posts[1].author.username + "\n"
if len(posts) >= 3:
tourn_winners_3.append(posts[2].author)
resp += " 3: " + posts[2].author.username + "\n"
看起来很简单,但是由于某种原因,结果是错误的。
因此,进行的查询是:
SELECT "blog_post"."id", "blog_post"."title", "blog_post"."slug", "blog_post"."a
uthor_id", "blog_post"."creator_ip", "blog_post"."body", "blog_post"."tease", "b
log_post"."status", "blog_post"."allow_comments", "blog_post"."publish", "blog_p
ost"."created_at", "blog_post"."updated_at", "blog_post"."markup", "blog_post"."
tags", "blog_post"."category_id" FROM "blog_post" WHERE ("blog_post"."status" =
2 AND "blog_post"."created_at" BETWEEN 2008-12-21 00:00:00 and 2009-01-04 00:00
:00) ORDER BY "blog_post"."publish" DESC
似乎posts.extra()根本没有应用于查询...
最佳答案
我认为您需要将posts
分配给posts.extra()
的返回值:
posts = posts.extra(select={'score': """
SELECT SUM(vote)
FROM %s
WHERE content_type_id = %s
AND object_id = %s.id
AND voted_at > DATE(%s)
AND voted_at < DATE(%s)
""" % (qn(Vote._meta.db_table), ctype.id, qn(Post._meta.db_table), start, end)},
order_by=['-score'])
关于python - 用django-voting投票解决问题,我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/544597/