通过对另一个表中的值进行分组来创建订单表 [英] Order table by grouping values in another table

问题描述

我有一个问题表：title
每个问题在另一个表中有答案：text，question_id
每个答案在另一个表中有投票：answer_id

I have a table of questions: title Each question has answers, in another table: text, question_id Each answer has votes, in another table: answer_id

我可以要求总投票

question.votes.count

我已经看过如何将投票db分组到
http://guides.rubyonrails.org/active_record_querying.html#group

I have seen how to group the votes db at http://guides.rubyonrails.org/active_record_querying.html#group

Vote.group("answer_id")

但我想订购我的问题投票。这是通过另一个表的分组从表中排序数组。这是可能吗？

But I want to order my questions by votes. That is ordering an array from a table via the grouping of another table. Is that possible?

q=Question.last
q.answers.order_by_vote #How to do this?

我想我的答案可能是在回答模型上做一个范围，投票属于这个问题。对不对？

I think my answer could be doing a scope on the answer model that makes the grouping on the subset of votes that belong to the question. Am I right?

谢谢。

推荐答案

通过投票计数，使用我的链接视图中的排序方法来组织我的链接：

I just figured out a way to organize my links by vote count, using the sort method in my links view:

<％@ user.links.sort {| a，b | b.votes.sum（：score）= a.votes.sum（：score）} .each do | link | ％>

votes.sum（：score）从投票表中获取特定链接的投票数。

votes.sum(:score) grabs the number of votes a particular link has from the votes table.

希望有所帮助。

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