{"author_url":"https://blog.hatena.ne.jp/murajun1978/","title":"Rails\u3067\u5b50\u30c6\u30fc\u30d6\u30eb\u306e\u30b9\u30b3\u30fc\u30d7\u3092\u4f7f\u3046\u30d8(^o^)\u30ce","categories":["Rails","Ruby"],"published":"2014-09-07 23:40:09","image_url":null,"version":"1.0","url":"https://murajun1978.hatenadiary.com/entry/2014/09/07/234009","blog_title":"Murajun's Style","provider_name":"Hatena Blog","height":"190","html":"<iframe src=\"https://hatenablog-parts.com/embed?url=https%3A%2F%2Fmurajun1978.hatenadiary.com%2Fentry%2F2014%2F09%2F07%2F234009\" title=\"Rails\u3067\u5b50\u30c6\u30fc\u30d6\u30eb\u306e\u30b9\u30b3\u30fc\u30d7\u3092\u4f7f\u3046\u30d8(^o^)\u30ce - Murajun&#39;s Style\" class=\"embed-card embed-blogcard\" scrolling=\"no\" frameborder=\"0\" style=\"display: block; width: 100%; height: 190px; max-width: 500px; margin: 10px 0px;\"></iframe>","type":"rich","author_name":"murajun1978","width":"100%","blog_url":"https://murajun1978.hatenadiary.com/","provider_url":"https://hatena.blog","description":"\u4f8b\u3048\u3070\u3053\u3093\u306a\u611f\u3058\u306e\u30e2\u30c7\u30eb class User < ActiveRecord::Base has_many :posts end class Post < ActiveRecord::Base belongs_to :user scope :published, -> { where(published: true) } end \u516c\u958b\u4e2d\u306ePost\u3092\u53d6\u5f97\u3059\u308b\u5834\u5408\u306f\u3053\u3093\u306a\u611f\u3058\u3067\u3059\u3088\u306d\uff1f $ Post.published \u3093\u3058\u3083\u3001\u30e6\u30fc\u30b6\u306e\u516c\u958b\u3055\u308c\u3066\u3044\u308bPost\u3092\u53d6\u5f97\u3059\u308b\u5834\u5408\u306f\uff1f $ User.joins(:posts).where(posts: {published: true}) \u30a4\u30de\u30a4\u30c1\u3067\u3059\u306d\u30fc\u2026"}