{"id":12207,"date":"2020-11-17T10:07:30","date_gmt":"2020-11-17T01:07:30","guid":{"rendered":"http:\/\/www.code-magagine.com\/?p=12207"},"modified":"2023-05-27T22:45:26","modified_gmt":"2023-05-27T13:45:26","slug":"%e3%80%90ruby-on-rails%e3%80%91%e3%80%8c%e4%b8%bb%e3%82%ad%e3%83%bc%e3%80%8d%e3%81%ab%e3%81%a4%e3%81%84%e3%81%a6","status":"publish","type":"post","link":"http:\/\/www.code-magagine.com\/?p=12207","title":{"rendered":"\u3010Ruby on Rails\u3011\u300c\u4e3b\u30ad\u30fc\u300d\u3001\u300c\u8907\u5408\u30ad\u30fc\u300d\u3001\u300ccomposite_primary_keys\u300d\u306b\u3064\u3044\u3066"},"content":{"rendered":"<h2>Rails\u306e\u4e3b\u30ad\u30fc<\/h2>\n<p>\u57fa\u672c\u7684\u306b\u306fRails\u3067\u306f\u8907\u5408\u30ad\u30fc\u304c\u8a8d\u3081\u3089\u308c\u3066\u304a\u3089\u305a\u3001\u4e3b\u30ad\u30fc\u306b\u306f<span style=\"color: #ff0000;\"><strong>id\uff08\u81ea\u52d5\u3067\u4ed8\u52a0\u3055\u308c\u308b\uff09<\/strong><\/span>\u304c\u4f7f\u308f\u308c\u307e\u3059\u3002<\/p>\n<h2>\u4e3b\u30ad\u30fc\u3092\u5225\u306b\u8a2d\u5b9a\u3059\u308b\u3002<\/h2>\n<p>\u3082\u3057\u3001id\u4ee5\u5916\u3092\u4e3b\u30ad\u30fc\u306b\u3057\u305f\u3044\u5834\u5408\u306f\u3001create_table\u306e\u7b87\u6240\u306b\u300cid: false\u300d\u3092\u6307\u5b9a\u3057\u3066\u3001\u4e3b\u30ad\u30fc\u306b\u8a2d\u5b9a\u3057\u305f\u3044\u30ab\u30e9\u30e0\u306b\u5bfe\u3057\u3066\u300cprimary_key: true\u300d\u3092\u8a2d\u5b9a\u3057\u307e\u3059\u3002<\/p>\n<pre class=\"lang:default decode:true\">class CreateUsers &lt; ActiveRecord::Migration[6.0]\r\n  def change\r\n    create_table :users, id: false do |t|\r\n      t.integer :user_id, null: false, primary_key: true\r\n      t.string :name\r\n\r\n      t.timestamps\r\n    end\r\n  end\r\nend<\/pre>\n<h2>\u8907\u5408\u30ad\u30fc\u3092\u8a2d\u5b9a\u3059\u308b\u3002(<span style=\"color: #000000;\"><strong>composite_primary_keys<\/strong><\/span>)<\/h2>\n<p>\u57fa\u672c\u7684\u306bRails\u3067\u306f\u8907\u5408\u30ad\u30fc\u306f\u8a31\u3055\u308c\u3066\u3044\u306a\u3044\u3067\u3059\u304c\u3001\u4e0b\u8a18\u306e\u3088\u3046\u306a\u7406\u7531\u306b\u3088\u308a\u8907\u5408\u30ad\u30fc\u3092\u4f7f\u3044\u305f\u3044\u30b1\u30fc\u30b9\u3082\u3042\u308b\u306e\u3067\u306f\u306a\u3044\u304b\u3068\u601d\u3044\u307e\u3059\u3002<\/p>\n<ul>\n<li>\u7121\u99c4\u306a\u30ab\u30e9\u30e0\u304c\u5897\u3048\u308b\u3002<\/li>\n<li>\u30b7\u30b9\u30c6\u30e0\u79fb\u884c\u306e\u969b\u306b\u4e0d\u8981\u306a\u30ab\u30e9\u30e0\u3092\u5897\u3084\u3057\u305f\u304f\u306a\u3044\u3002<\/li>\n<\/ul>\n<p><span style=\"color: #ff0000;\"><span style=\"color: #000000;\">\u305d\u3046\u3057\u305f\u5834\u5408\u306b\u304a\u3044\u3066\u306f<\/span><strong>composite_primary_keys<\/strong><\/span>\u3068\u3044\u3046Gem\u3092\u4f7f\u3044\u307e\u3059\u3002<\/p>\n<h2>\u5b9f\u88c5\u65b9\u6cd5<\/h2>\n<p>\u5148\u306b\u4e0b\u8a18\u306e\u3088\u3046\u306a\u611f\u3058\u3067\u30c6\u30fc\u30d6\u30eb\u3092\u4f5c\u3063\u3066\u304a\u304d\u307e\u3059\u3002\uff08\u30de\u30a4\u30b0\u30ec\u30fc\u30b7\u30e7\u30f3\u30d5\u30a1\u30a4\u30eb\u3067\u306f\u8907\u5408\u30ad\u30fc\u306f\u4f5c\u308c\u306a\u3044\u3088\u3046\u306b\u306a\u3063\u3066\u3044\u308b\u3088\u3046\u3067\u3001\u76f4\u63a5SQL\u3092\u5b9f\u884c\u3057\u307e\u3059\u3002\uff09<\/p>\n<pre class=\"lang:default decode:true\">CREATE TABLE `\u30c6\u30fc\u30d6\u30eb\u540d` (\r\n  `\u30ad\u30fc\uff11` string(255) NOT NULL,\r\n  `\u30ad\u30fc2` int(11) NOT NULL,\r\n  `created_at` datetime DEFAULT NULL,\r\n  `updated_at` datetime DEFAULT NULL,\r\n  PRIMARY KEY (`\u30ad\u30fc1`, `\u30ad\u30fc2`)\r\n);<\/pre>\n<p>composite_primary_keys\u3092\u5165\u308c\u308b\u3068\u30e2\u30c7\u30eb\u5185\u3067\u4e0b\u8a18\u306e\u69cb\u6587\u3092\u4f7f\u3046\u3053\u3068\u304c\u3067\u304d\u308b\u3088\u3046\u306b\u306a\u308a\u307e\u3059\u3002<\/p>\n<pre class=\"lang:default decode:true\">class \u30e2\u30c7\u30eb\u540d &lt; ApplicationRecord\r\n  self.primary_keys = :\u30ad\u30fc\uff11, :\u30ad\u30fc2\r\nend<\/pre>\n<p>\u30d7\u30ed\u30b0\u30e9\u30e0\u5185\u3067\u306f\u4e0b\u8a18\u306e\u3088\u3046\u306b\u6307\u5b9a\u3057\u305f\u3089\u8907\u5408\u30ad\u30fc\u306e\u5024\u304c\u53d6\u5f97\u3067\u304d\u307e\u3059\u3002\uff08\u300c\u30ad\u30fc1,\u30ad\u30fc2\u300d\u306e\u5f62\u3067\u8907\u5408\u30ad\u30fc\u304c\u683c\u7d0d\u3055\u308c\u3066\u3044\u307e\u3059\u3002\uff09<\/p>\n<pre class=\"lang:default decode:true\">params[:id]<\/pre>\n<p>\u8907\u5408\u30ad\u30fc\u3092\u4f7f\u3063\u3066\u30ab\u30e9\u30e0\u306e\u4e2d\u306e\u5024\u3092\u691c\u7d22\u3067\u304d\u307e\u3059\u3002<\/p>\n<pre class=\"lang:default decode:true \">\u30e2\u30c7\u30eb\u540d.find(params[:id])<\/pre>\n","protected":false},"excerpt":{"rendered":"Rails\u306e\u4e3b\u30ad\u30fc \u57fa\u672c\u7684\u306b\u306fRails\u3067\u306f\u8907\u5408\u30ad\u30fc\u304c\u8a8d\u3081\u3089\u308c\u3066\u304a\u3089\u305a\u3001\u4e3b\u30ad\u30fc\u306b\u306fid\uff08\u81ea\u52d5\u3067\u4ed8\u52a0\u3055\u308c\u308b\uff09\u304c\u4f7f\u308f\u308c\u307e\u3059\u3002 \u4e3b\u30ad\u30fc\u3092\u5225\u306b\u8a2d\u5b9a\u3059\u308b\u3002 \u3082\u3057\u3001id\u4ee5\u5916\u3092\u4e3b\u30ad\u30fc\u306b\u3057\u305f\u3044\u5834\u5408\u306f\u3001create_table\u306e\u7b87\u6240\u306b\u300ci [&hellip;]","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[36],"tags":[],"_links":{"self":[{"href":"http:\/\/www.code-magagine.com\/index.php?rest_route=\/wp\/v2\/posts\/12207"}],"collection":[{"href":"http:\/\/www.code-magagine.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.code-magagine.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.code-magagine.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/www.code-magagine.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=12207"}],"version-history":[{"count":9,"href":"http:\/\/www.code-magagine.com\/index.php?rest_route=\/wp\/v2\/posts\/12207\/revisions"}],"predecessor-version":[{"id":20504,"href":"http:\/\/www.code-magagine.com\/index.php?rest_route=\/wp\/v2\/posts\/12207\/revisions\/20504"}],"wp:attachment":[{"href":"http:\/\/www.code-magagine.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=12207"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.code-magagine.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=12207"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.code-magagine.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=12207"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}