Question

我有一个名为Author的模型。一位作者有很多文章。文章有一个名为.published的范围：where（published：true）。

我想加载作者，发表文章。我试过了：

Author.includes(:articles.published).find(params[:author_id])

但是这会引发错误：未定义的方法＆＃39;已发布＆＃39;。有什么想法吗？

Answer 1

我认为最好的解决方案是：

class Author < ActiveRecord::Base 
    scope :with_published_articles, -> { includes(:articles).where(articles: { published: true}) }
end

或者您可以创建范围：

Author.with_published_articles.find(params[:author_id].to_s)

然后：

<tr>
  <td><font color="black">Time:</td>
  <td colspan = "2"><input type = "time" name = "time_hr"></td>
  </tr>

Answer 2

我会在名为Author的{{1}}上指定范围，如下所示：

with_published_articles

这将解决您的问题，以便在scope :with_published_articles, -> { joins(:articles).merge(Article.published) }模型上指定where(active: true)，以防Author行为和published将来发生变化。

所以现在你可以打电话：

Article

Answer 3

试试这段代码：

(\d{2}:) (\d{2}:) ([0-9,]+) -> (\d{2}:) (\d{2}:) ([0-9,]+)

您可以在此处找到有关上述示例的更多信息： includes api doc

Answer 4

使用：

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在Autor上定义范围

class Articles < ActiveRecord::Base 
    scope :published, -> { where(articles: {published: true}) }
end

或

class Author < ActiveRecord::Base 
    scope :with_published_articles, -> { joins(:articles).merge(Articles.published) }
end

Rails包括范围

4 个答案: