{"id":2953,"date":"2021-12-03T17:13:06","date_gmt":"2021-12-03T08:13:06","guid":{"rendered":"https:\/\/suzutukiblog.com\/?p=2953"},"modified":"2022-01-23T05:59:06","modified_gmt":"2022-01-22T20:59:06","slug":"rails-tutorial-13","status":"publish","type":"post","link":"https:\/\/suzutukiblog.com\/index.php\/2021\/12\/03\/rails-tutorial-13\/","title":{"rendered":"Rails-tutorial\u306e\u307e\u3068\u3081(\u7b2c13\u7ae0\u30e6\u30fc\u30b6\u30fc\u306e\u30de\u30a4\u30af\u30ed\u30dd\u30b9\u30c8 \u4e3b\u306b\u6f14\u7fd2)"},"content":{"rendered":"

\u305d\u306e12\u304b\u3089\u7d9a\u304f<\/a><\/p>\n

\u7b2c13\u7ae0\u30e6\u30fc\u30b6\u30fc\u306e\u30de\u30a4\u30af\u30ed\u30dd\u30b9\u30c8<\/h3>\n

\u30e6\u30fc\u30b6\u30fc\u3068\u3044\u3046\u30ea\u30bd\u30fc\u30b9\u3060\u3051\u304c\u3001
\nActive Record\u306b\u3088\u3063\u3066\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u4e0a\u306e\u30c6\u30fc\u30d6\u30eb\u3068\u7d10\u4ed8\u3044\u3066\u3044\u307e\u3059\u3002
\n\u5168\u3066\u306e\u6e96\u5099\u304c\u6574\u3063\u305f\u4eca\u3001
\n\u30e6\u30fc\u30b6\u30fc\u304c\u77ed\u3044\u30e1\u30c3\u30bb\u30fc\u30b8\u3092\u6295\u7a3f\u3067\u304d\u308b\u3088\u3046\u306b\u3059\u308b\u305f\u3081\u306e\u30ea\u30bd\u30fc\u30b9\u300c\u30de\u30a4\u30af\u30ed\u30dd\u30b9\u30c8\u300d\u3092\u8ffd\u52a0\u3057\u3066\u3044\u304d\u307e\u3059\u3002<\/p>\n

User\u30e2\u30c7\u30eb\u3068has_many\u304a\u3088\u3073belongs_to\u30e1\u30bd\u30c3\u30c9\u3092\u4f7f\u3063\u3066\u95a2\u9023\u4ed8\u3051\u3092\u884c\u3044\u3001\u3055\u3089\u306b\u3001\u7d50\u679c\u3092\u51e6\u7406\u3057\u8868\u793a\u3059\u308b\u305f\u3081\u306b\u5fc5\u8981\u306a\u30d5\u30a9\u30fc\u30e0\u3068\u305d\u306e\u90e8\u54c1\u3092\u4f5c\u6210\u3057\u307e\u3059<\/p>\n

13.1\u00a0<\/span>Micropost\u30e2\u30c7\u30eb<\/h3>\n

\u3053\u306e\u65b0\u3057\u3044Micropost\u30e2\u30c7\u30eb\u3082\u30c7\u30fc\u30bf\u691c\u8a3c\u3068User\u30e2\u30c7\u30eb\u306e\u95a2\u9023\u4ed8\u3051\u3092\u542b\u3093\u3067\u3044\u307e\u3059\u3002
\n\u4ee5\u524d\u306e\u30e2\u30c7\u30eb\u3068\u306f\u9055\u3063\u3066\u3001
\n\u4eca\u56de\u306e\u30de\u30a4\u30af\u30ed\u30dd\u30b9\u30c8\u30e2\u30c7\u30eb\u306f\u5b8c\u5168\u306b\u30c6\u30b9\u30c8\u3055\u308c\u3001
\n\u30c7\u30d5\u30a9\u30eb\u30c8\u306e\u9806\u5e8f\u3092\u6301\u3061\u3001\u307e\u305f\u89aa\u3067\u3042\u308b\u30e6\u30fc\u30b6\u30fc\u304c\u7834\u68c4\u3055\u308c\u305f\u5834\u5408\u306b\u306f\u81ea\u52d5\u7684\u306b\u7834\u68c4\u3055\u308c\u308b\u3088\u3046\u306b\u3057\u307e\u3059\u3002<\/p>\n

13.1.1\u00a0<\/span>\u57fa\u672c\u7684\u306a\u30e2\u30c7\u30eb<\/h3>\n

Micropost\u30e2\u30c7\u30eb\u306f\u3001\u30de\u30a4\u30af\u30ed\u30dd\u30b9\u30c8\u306e\u5185\u5bb9\u3092\u4fdd\u5b58\u3059\u308bcontent\u5c5e\u6027\u3068\u3001\u7279\u5b9a\u306e\u30e6\u30fc\u30b6\u30fc\u3068\u30de\u30a4\u30af\u30ed\u30dd\u30b9\u30c8\u3092\u95a2\u9023\u4ed8\u3051\u308buser_id\u5c5e\u6027\u306e2\u3064\u306e\u5c5e\u6027\u3060\u3051\u3092\u6301\u3061\u307e\u3059\u3002<\/p>\n

\u30de\u30a4\u30af\u30ed\u30dd\u30b9\u30c8\u306e\u6295\u7a3f\u306bString\u578b\u3067\u306f\u306a\u304fText\u578b\u3092\u4f7f\u3063\u3066\u3044\u308b\u3002
\nText\u578b\u306e\u65b9\u304c\u8868\u73fe\u8c4a\u304b\u306a\u30de\u30a4\u30af\u30ed\u30dd\u30b9\u30c8\u3092\u5b9f\u73fe\u3067\u304d\u308b\u304b\u3089
\nText\u578b\u306e\u65b9\u304c\u5c06\u6765\u306b\u304a\u3051\u308b\u67d4\u8edf\u6027\u306b\u5bcc\u3093\u3067\u3044\u3066
\nText\u7528\u306e\u30c6\u30ad\u30b9\u30c8\u30a8\u30ea\u30a2\u3092\u4f7f\u3046\u305f\u3081\u3001
\n\u3088\u308a\u81ea\u7136\u306a\u6295\u7a3f\u30d5\u30a9\u30fc\u30e0\u304c\u5b9f\u73fe\u3067\u304d\u307e\u3059\u3002<\/p>\n

rails generate model Micropost content:text user:references<\/strong><\/pre>\n
ApplicationRecord\u3092\u7d99\u627f\u3057\u305f\u30e2\u30c7\u30eb\u304c\u4f5c\u3089\u308c\u307e\u3059\u3002
\n\u305f\u3060\u3057\u3001\u4eca\u56de\u306f\u751f\u6210\u3055\u308c\u305f\u30e2\u30c7\u30eb\u306e\u4e2d\u306b\u3001
\n\u30e6\u30fc\u30b6\u30fc\u3068\uff11\u5bfe\uff11\u306e\u95a2\u4fc2\u3067\u3042\u308b\u3053\u3068\u3092\u8868\u3059\u3002
\nbelongs_to\u306e\u30b3\u30fc\u30c9\u3082\u8ffd\u52a0\u3055\u308c\u3066\u3044\u307e\u3059\u3002
\nuser:references\u3068\u3044\u3046\u5f15\u6570\u3082\u542b\u3081\u3066\u3044\u305f\u304b\u3089\u3067\u3059\u3002<\/p>\n
\u3053\u306egenerate\u30b3\u30de\u30f3\u30c9\u306fmicroposts\u30c6\u30fc\u30d6\u30eb\u3092\u4f5c\u6210\u3059\u308b\u305f\u3081\u306e
\n\u30de\u30a4\u30b0\u30ec\u30fc\u30b7\u30e7\u30f3\u30d5\u30a1\u30a4\u30eb\u3092\u751f\u6210\u3057\u307e\u3059\u3002<\/p>\n
User\u30e2\u30c7\u30eb\u3068\u306e\u6700\u5927\u306e\u9055\u3044\u306freferences\u578b\u3092\u5229\u7528\u3057\u3066\u3044\u308b\u70b9\u3067\u3059\u3002
\n\u3053\u308c\u3092\u5229\u7528\u3059\u308b\u3068\u3001\u81ea\u52d5\u7684\u306b\u30a4\u30f3\u30c7\u30c3\u30af\u30b9\u3068\u5916\u90e8\u30ad\u30fc\u53c2\u7167\u4ed8\u304d\u306euser_id\u30ab\u30e9\u30e0\u304c\u8ffd\u52a0\u3055\u308c\u3001
\nUser\u3068Micropost\u3092\u95a2\u9023\u4ed8\u3051\u3059\u308b\u4e0b\u6e96\u5099\u3092\u3057\u3066\u304f\u308c\u307e\u3059\u3002<\/p>\n
\u30a4\u30f3\u30c7\u30c3\u30af\u30b9\u304c\u4ed8\u4e0e\u3055\u308c\u305fMicropost\u306e\u30de\u30a4\u30b0\u30ec\u30fc\u30b7\u30e7\u30f3
\ndb\/migrate\/[timestamp]_create_microposts.rb<\/strong><\/p>\n
  def<\/span> change<\/span>\r\n    create_table<\/span> :microposts<\/span> do<\/span> |<\/span>t<\/span>|<\/span>\r\n      t<\/span>.<\/span>text<\/span> :content<\/span>\r\n      t<\/span>.<\/span>references<\/span> :user<\/span>,<\/span> foreign_key<\/span>:<\/span> true<\/span>\r\n\r\n      t<\/span>.<\/span>timestamps<\/span>\r\n    end<\/span>\r\n    add_index<\/span> :microposts<\/span>,<\/span> [<\/span>:user_id<\/span>,<\/span> :created_at<\/span>]<\/span>\r\n<\/span>  end<\/span>\r\nend<\/span><\/strong><\/pre>\n
user_id\u3068created_at\u30ab\u30e9\u30e0\u306b\u30a4\u30f3\u30c7\u30c3\u30af\u30b9\u304c\u4ed8\u4e0e\u3055\u308c\u3066\u3044\u308b\u3053\u3068\u306b\u6ce8\u76ee\u3053\u3046\u3059\u308b\u3053\u3068\u3067\u3001
\nuser_id\u306b\u95a2\u9023\u4ed8\u3051\u3089\u308c\u305f\u3059\u3079\u3066\u306e\u30de\u30a4\u30af\u30ed\u30dd\u30b9\u30c8\u3092
\n\u4f5c\u6210\u6642\u523b\u306e\u9006\u9806\u3067\u53d6\u308a\u51fa\u3057\u3084\u3059\u304f\u306a\u308a\u307e\u3059\u3002<\/p>\n
user_id\u3068created_at\u306e\u4e21\u65b9\u3092\uff11\u3064\u306e\u914d\u5217\u306b\u542b\u3081\u3066\u3044\u308b\u70b9\u306b\u3082\u6ce8\u76ee\u3067\u3059\u3002
\n\u3053\u3046\u3059\u308b\u3053\u3068\u3067Active Record\u306f\u3001\u4e21\u65b9\u306e\u30ad\u30fc\u3092\u540c\u6642\u306b\u6271\u3046\u8907\u5408\u30ad\u30fc\u30a4\u30f3\u30c7\u30c3\u30af\u30b9(Multiple Key Index) \u3092\u4f5c\u6210\u3057\u307e\u3059\u3002<\/p>\n
rails db:migrate<\/strong><\/pre>\n
<\/p>\n
\u6f14\u7fd2<\/h3>\n
1:Rails\u30b3\u30f3\u30bd\u30fc\u30eb\u3067Micropost.new\u3092\u5b9f\u884c\u3057\u3001\u30a4\u30f3\u30b9\u30bf\u30f3\u30b9\u3092\u5909\u6570micropost\u306b\u4ee3\u5165\u3057\u3066\u304f\u3060\u3055\u3044\u3002
\n\u305d\u306e\u5f8c\u3001user_id\u306b\u6700\u521d\u306e\u30e6\u30fc\u30b6\u30fc\u306eid\u3092\u3001content\u306b
\n“Lorem ipsum” \u3092\u305d\u308c\u305e\u308c\u4ee3\u5165\u3057\u3066\u307f\u3066\u304f\u3060\u3055\u3044\u3002
\n\u3053\u306e\u6642\u70b9\u3067\u306f\u3001micropost\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306e\u30de\u30b8\u30c3\u30af\u30ab\u30e9\u30e0 (created_at\u3068updated_at)\u306b\u306f\u4f55\u304c\u5165\u3063\u3066\u3044\u308b\u3067\u3057\u3087\u3046\u304b?<\/p>\n
>> micropost = Micropost.new<\/strong>\r\n=> #<Micropost id: nil, content: nil, user_id: nil, created_at: nil, updated_at: nil><\/strong>\r\n>> micropost.user_id = User.first.id<\/strong>\r\nUser Load (0.2ms) SELECT \"users\".* FROM \"users\" ORDER BY \"users\".\"id\" ASC LIMIT ? [[\"LIMIT\", 1]]<\/strong>\r\n=> 1<\/strong>\r\n>> micropost.content = \"Lorem ipsum\"<\/strong>\r\n=> \"Lorem ipsum\"<\/strong>\r\n>> micropost.created_at<\/strong>\r\n=> nil<\/strong>\r\n>> micropost.updated_at<\/strong>\r\n=> nil<\/strong><\/pre>\n
2:\u5148\u307b\u3069\u4f5c\u3063\u305f\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u3092\u4f7f\u3063\u3066\u3001micropost.user\u3092\u5b9f\u884c\u3057\u3066\u307f\u307e\u3057\u3087\u3046\u3002
\n\u3069\u306e\u3088\u3046\u306a\u7d50\u679c\u304c\u8fd4\u3063\u3066\u304f\u308b\u3067\u3057\u3087\u3046\u304b? \u307e\u305f\u3001micropost.user.name\u3092\u5b9f\u884c\u3057\u305f
\n\u5834\u5408\u306e\u7d50\u679c\u306f\u3069\u3046\u306a\u308b\u3067\u3057\u3087\u3046\u304b?<\/p>\n
micropost.user<\/strong>\r\nUser Load (1.3ms) SELECT \"users\".* FROM \"users\" WHERE \"users\".\"id\" = ? LIMIT ? [[\"id\", 1], [\"LIMIT\", 1]]<\/strong>\r\n=> #<User id: 1, name: \"Example User\", email: \"example@railstutorial.org\", created_at: \"2020-04-07 13:46:42\", updated_at: \"2020-04-09 06:04:49\", password_digest: \"$2a$10$GANEfKFrSAstHXyU9iKuCuZCqGiIkWq8G9omIW2kfFD...\", remember_digest: nil, admin: true, activation_digest: \"$2a$10$PRCrEV3JLxiTFRfnbnQSquram12Njfl4cs9ieMebt3a...\", activated: true, activated_at: \"2020-04-07 13:46:41\", reset_digest: \"$2a$10$rqLaoPfGBIsYQ83ULnk3JO4ozC9kCB1tw2Z9dF55ysh...\", reset_sent_at: \"2020-04-09 06:04:49\"><\/strong><\/pre>\n
micropost\u306bid\u3092\u4ed8\u4e0e\u3059\u308b\u3053\u3068\u3067\u3001user\u3068name\u304c\u304d\u3061\u3093\u3068\u7d10\u3065\u3044\u3066\u3044\u308b\u3002<\/p>\n
3:\u5148\u307b\u3069\u4f5c\u3063\u305fmicropost\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u3092\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u306b\u4fdd\u5b58\u3057\u3066\u307f\u307e\u3057\u3087\u3046\u3002
\n\u3053\u306e\u6642\u70b9\u3067\u3082\u3046\u4e00\u5ea6\u30de\u30b8\u30c3\u30af\u30ab\u30e9\u30e0\u306e\u5185\u5bb9\u3092\u8abf\u3079\u3066\u307f\u307e\u3057\u3087\u3046\u3002
\n\u4eca\u5ea6\u306f\u3069\u306e\u3088\u3046\u306a\u5024\u304c\u5165\u3063\u3066\u3044\u308b\u3067\u3057\u3087\u3046\u304b?<\/p>\n
micropost.save<\/strong>\r\n(0.1ms) SAVEPOINT active_record_1<\/strong>\r\nSQL (2.1ms) INSERT INTO \"microposts\" (\"content\", \"user_id\", \"created_at\", \"updated_at\") VALUES (?, ?, ?, ?) [[\"content\", \"Lorem ipsum\"], [\"user_id\", 1], [\"created_at\", \"2020-04-09 13:48:05.586960\"], [\"updated_at\", \"2020-04-09 13:48:05.586960\"]]<\/strong>\r\n(0.1ms) RELEASE SAVEPOINT active_record_1<\/strong>\r\n=> true<\/strong>\r\n>> micropost.created_at<\/strong>\r\n=> Thu, 09 Apr 2020 13:48:05 UTC +00:00<\/strong>\r\n>> micropost.updated_at<\/strong>\r\n=> Thu, 09 Apr 2020 13:48:05 UTC +00:00<\/strong><\/pre>\n
13.1.2\u00a0<\/span>Micropost\u306e\u30d0\u30ea\u30c7\u30fc\u30b7\u30e7\u30f3<\/h3>\n
\u65b0\u3057\u3044Micropost\u306e\u6709\u52b9\u6027\u306b\u5bfe\u3059\u308b\u30c6\u30b9\u30c8\u00a0green<\/strong><\/span><\/span><\/div>\n
test\/models\/micropost_test.rb<\/code><\/span><\/strong><\/div>\n
\n
\n
require<\/span> 'test_helper'<\/span>\r\nclass<\/span> MicropostTest<\/span> <<\/span> ActiveSupport<\/span>::<\/span>TestCase<\/span>\r\n  def<\/span> setup<\/span>\r\n    @user<\/span> =<\/span> users<\/span>(<\/span>:michael<\/span>)<\/span>\r\n    # \u3053\u306e\u30b3\u30fc\u30c9\u306f\u6163\u7fd2\u7684\u306b\u6b63\u3057\u304f\u306a\u3044<\/span>\r\n<\/span>    @micropost<\/span> =<\/span> Micropost<\/span>.<\/span>new<\/span>(<\/span>content<\/span>:<\/span> \"Lorem ipsum\"<\/span>,<\/span> user_id<\/span>:<\/span> @user<\/span>.<\/span>id<\/span>)<\/span>\r\n<\/span>  end<\/span>\r\n  test<\/span> \"should be valid\"<\/span> do<\/span>\r\n    assert<\/span> @micropost<\/span>.<\/span>valid?<\/span>\r\n  end<\/span>\r\n  test<\/span> \"user id should be present\"<\/span> do<\/span>\r\n    @micropost<\/span>.<\/span>user_id<\/span> =<\/span> nil<\/span>\r\n    assert_not<\/span> @micropost<\/span>.<\/span>valid?<\/span>\r\n  end<\/span>\r\nend<\/span><\/strong><\/pre>\n<\/div>\n<\/div>\n
 <\/p>\n
\u30de\u30a4\u30af\u30ed\u30dd\u30b9\u30c8\u306euser_id<\/code>\u306b\u5bfe\u3059\u308b\u691c\u8a3c\u00a0green<\/strong><\/span><\/span><\/div>\n
app\/models\/micropost.rb<\/code><\/span><\/strong><\/div>\n
\n
\n
class<\/span> Micropost<\/span> <<\/span> ApplicationRecord<\/span>\r\n  belongs_to<\/span> :user<\/span>\r\n  validates<\/span> :user_id<\/span>,<\/span> presence<\/span>:<\/span> true<\/span>\r\n<\/span>end<\/span><\/strong><\/pre>\n<\/div>\n<\/div>\n
green<\/strong><\/span><\/span><\/div>\n
\n
\n
rails test:models<\/strong><\/pre>\n<\/div>\n<\/div>\n
Micropost\u30e2\u30c7\u30eb\u306e\u30d0\u30ea\u30c7\u30fc\u30b7\u30e7\u30f3\u306b\u5bfe\u3059\u308b\u30c6\u30b9\u30c8\u00a0red<\/strong><\/span><\/span><\/div>\n
test\/models\/micropost_test.rb<\/code><\/span><\/strong><\/div>\n
\n
\n
require<\/span> 'test_helper'<\/span>\r\nclass<\/span> MicropostTest<\/span> <<\/span> ActiveSupport<\/span>::<\/span>TestCase<\/span>\r\n  def<\/span> setup<\/span>\r\n    @user<\/span> =<\/span> users<\/span>(<\/span>:michael<\/span>)<\/span>\r\n    @micropost<\/span> =<\/span> Micropost<\/span>.<\/span>new<\/span>(<\/span>content<\/span>:<\/span> \"Lorem ipsum\"<\/span>,<\/span> user_id<\/span>:<\/span> @user<\/span>.<\/span>id<\/span>)<\/span>\r\n  end<\/span>\r\n  test<\/span> \"should be valid\"<\/span> do<\/span>\r\n    assert<\/span> @micropost<\/span>.<\/span>valid?<\/span>\r\n  end<\/span>\r\n  test<\/span> \"user id should be present\"<\/span> do<\/span>\r\n    @micropost<\/span>.<\/span>user_id<\/span> =<\/span> nil<\/span>\r\n    assert_not<\/span> @micropost<\/span>.<\/span>valid?<\/span>\r\n  end<\/span>\r\n  test<\/span> \"content should be present\"<\/span> do<\/span>\r\n<\/span>    @micropost<\/span>.<\/span>content<\/span> =<\/span> \"   \"<\/span>\r\n<\/span>    assert_not<\/span> @micropost<\/span>.<\/span>valid?<\/span>\r\n<\/span>  end<\/span><\/span>\r\n  test<\/span> \"content should be at most 140 characters\"<\/span> do<\/span>\r\n<\/span>    @micropost<\/span>.<\/span>content<\/span> =<\/span> \"a\"<\/span> *<\/span> 141<\/span>\r\n<\/span>    assert_not<\/span> @micropost<\/span>.<\/span>valid?<\/span>\r\n<\/span>  end<\/span>\r\n<\/span>end<\/span><\/strong><\/pre>\n<\/div>\n<\/div>\n
Micropost\u30e2\u30c7\u30eb\u306e\u30d0\u30ea\u30c7\u30fc\u30b7\u30e7\u30f3\u00a0green<\/strong><\/span><\/span><\/div>\n
app\/models\/micropost.rb<\/code><\/span><\/strong><\/div>\n
\n
\n
class<\/span> Micropost<\/span> <<\/span> ApplicationRecord<\/span>\r\n  belongs_to<\/span> :user<\/span>\r\n  validates<\/span> :user_id<\/span>,<\/span> presence<\/span>:<\/span> true<\/span>\r\n  validates<\/span> :content<\/span>,<\/span> presence<\/span>:<\/span> true<\/span>,<\/span> length<\/span>:<\/span> {<\/span> maximum<\/span>:<\/span> 140<\/span> }<\/span>\r\n<\/span>end<\/span><\/strong><\/pre>\n<\/div>\n<\/div>\n
\n
green<\/strong><\/span><\/span><\/div>\n
\n
\n
rails test\r\n<\/strong><\/pre>\n<\/div>\n<\/div>\n<\/div>\n
\n
\u6f14\u7fd2<\/h3>\n
<\/div>\n
Rails\u30b3\u30f3\u30bd\u30fc\u30eb\u3092\u958b\u304d\u3001user_id<\/code>\u3068content<\/code>\u304c\u7a7a\u306b\u306a\u3063\u3066\u3044\u308bmicropost\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u3092\u4f5c\u3063\u3066\u307f\u3066\u304f\u3060\u3055\u3044\u3002\u3053\u306e\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306b\u5bfe\u3057\u3066valid?<\/code>\u3092\u5b9f\u884c\u3059\u308b\u3068\u3001\u5931\u6557\u3059\u308b\u3053\u3068\u3092\u78ba\u8a8d\u3057\u3066\u307f\u307e\u3057\u3087\u3046\u3002\u307e\u305f\u3001\u751f\u6210\u3055\u308c\u305f\u30a8\u30e9\u30fc\u30e1\u30c3\u30bb\u30fc\u30b8\u306b\u306f\u3069\u3093\u306a\u5185\u5bb9\u304c\u66f8\u304b\u308c\u3066\u3044\u308b\u3067\u3057\u3087\u3046\u304b?
\n<\/span><\/p>\n
\u52d5\u4f5c\u78ba\u8a8d\u3059\u308b\u3060\u3051<\/p>\n
\u30b3\u30f3\u30bd\u30fc\u30eb\u3092\u958b\u304d\u3001\u4eca\u5ea6\u306fuser_id<\/code>\u304c\u7a7a\u3067content<\/code>\u304c141\u6587\u5b57\u4ee5\u4e0a\u306emicropost\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u3092\u4f5c\u3063\u3066\u307f\u3066\u304f\u3060\u3055\u3044\u3002\u3053\u306e\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306b\u5bfe\u3057\u3066valid?<\/code>\u3092\u5b9f\u884c\u3059\u308b\u3068\u3001\u5931\u6557\u3059\u308b\u3053\u3068\u3092\u78ba\u8a8d\u3057\u3066\u307f\u307e\u3057\u3087\u3046\u3002\u307e\u305f\u3001\u751f\u6210\u3055\u308c\u305f\u30a8\u30e9\u30fc\u30e1\u30c3\u30bb\u30fc\u30b8\u306b\u306f\u3069\u3093\u306a\u5185\u5bb9\u304c\u66f8\u304b\u308c\u3066\u3044\u308b\u3067\u3057\u3087\u3046\u304b?<\/p>\n
\u52d5\u4f5c\u78ba\u8a8d\u3059\u308b\u3060\u3051<\/p>\n
13.1.3\u00a0<\/span>User\/Micropost\u306e\u95a2\u9023\u4ed8\u3051<\/h3>\n<\/div>\n
belongs_to\/has_many\u95a2\u9023\u4ed8\u3051\u3092\u4f7f\u3046\u3053\u3068\u3067
\n\u2193\u306b\u793a\u3059\u3088\u3046\u306a\u30e1\u30bd\u30c3\u30c9\u3092Rails\u3067\u4f7f\u3048\u308b\u3088\u3046\u306b\u306a\u308a\u307e\u3059
\n\u3053\u306e\u30e1\u30bd\u30c3\u30c9\u306b\u306a\u3063\u3066\u3044\u308b\u3053\u3068\u306b\u6ce8\u610f\u3057\u3066\u304f\u3060\u3055\u3044\u3002<\/p>\n
user.microposts.create<\/strong>\r\nuser.microposts.create!<\/strong>\r\nuser.microposts.build<\/strong><\/pre>\n
@user = users(:michael)<\/strong>\r\n# \u3053\u306e\u30b3\u30fc\u30c9\u306f\u6163\u7fd2\u7684\u306b\u6b63\u3057\u304f\u306a\u3044<\/strong>\r\n@micropost = Micropost.new(content: \"Lorem ipsum\", user_id: @user.id)<\/strong><\/pre>\n
\u3068\u3044\u3046\u66f8\u304d\u65b9\u304c\u3001\u6b21\u306e\u3088\u3046\u306b\u66f8\u304d\u63db\u3048\u3089\u308c\u307e\u3059\u3002<\/p>\n
@user = users(:michael)<\/strong>\r\n@micropost = @user.microposts.build(content: \"Lorem ipsum\")<\/strong><\/pre>\n
build\u30e1\u30bd\u30c3\u30c9\u306f\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u3092\u8fd4\u3057\u307e\u3059\u304c\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u306b\u306f\u53cd\u6620\u3055\u308c\u307e\u305b\u3093\u3002
\n\u4e00\u5ea6\u6b63\u3057\u3044\u95a2\u9023\u4ed8\u3051\u3092\u5b9a\u7fa9\u3057\u3066\u3057\u307e\u3048\u3070\u3001@micropost\u5909\u6570\u306euser_id\u306b\u306f\u3001\u95a2\u9023\u3059\u308b\u30e6\u30fc\u30b6\u30fc\u306eid\u304c\u81ea\u52d5\u7684\u306b\u8a2d\u5b9a\u3055\u308c\u307e\u3059\u3002<\/p>\n
 <\/p>\n
    \u30e1\u30bd\u30c3\u30c9                                    \u7528\u9014\r\nmicropost.user                 Micropost\u306b\u7d10\u4ed8\u3044\u305fUser\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u3092\u8fd4\u3059<\/strong>\r\n\r\nuser.microposts                User\u306e\u30de\u30a4\u30af\u30ed\u30dd\u30b9\u30c8\u306e\u96c6\u5408\u3092\u304b\u3048\u3059<\/strong>\r\n\r\nuser.microposts.create(arg)    user\u306b\u7d10\u4ed8\u3044\u305f\u30de\u30a4\u30af\u30ed\u30dd\u30b9\u30c8\u3092\u4f5c\u6210\u3059\u308b<\/strong>\r\n\r\nuser.microposts.create!(arg)   user\u306b\u7d10\u4ed8\u3044\u305f\u30de\u30a4\u30af\u30ed\u30dd\u30b9\u30c8\u3092\u4f5c\u6210\u3059\u308b (\u5931\u6557\u6642\u306b\u4f8b\u5916\u3092\u767a\u751f)<\/strong>\r\n\r\nuser.microposts.build(arg)     user\u306b\u7d10\u4ed8\u3044\u305f\u65b0\u3057\u3044Micropost\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u3092\u8fd4\u3059<\/strong>\r\n\r\nuser.microposts.find_by(id: 1) user\u306b\u7d10\u4ed8\u3044\u3066\u3044\u3066\u3001id\u304c1\u3067\u3042\u308b<\/strong>\r\n\u30de\u30a4\u30af\u30ed\u30dd\u30b9\u30c8\u3092\u691c\u7d22\u3059\u308b<\/strong>\r\n\r\nuser\/micropost\u95a2\u9023\u30e1\u30bd\u30c3\u30c9\u306e\u307e\u3068\u3081<\/strong><\/pre>\n
\u4e00\u65b9\u3001User\u30e2\u30c7\u30eb\u306e\u65b9\u3067\u306f\u3001has_many :microposts\u3068\u8ffd\u52a0\u3059\u308b\u5fc5\u8981\u304c\u3042\u308a\u307e\u3059\u3002<\/strong> \u3053\u3053\u306f\u81ea\u52d5\u7684\u306b\u751f\u6210\u3055\u308c\u306a\u3044\u306e\u3067\u3001\u624b\u52d5\u3067\u8ffd\u52a0\u3057\u3066\u304f\u3060\u3055\u3044<\/strong><\/p>\n
\u30de\u30a4\u30af\u30ed\u30dd\u30b9\u30c8\u304c\u30e6\u30fc\u30b6\u30fc\u306b\u6240\u5c5e\u3059\u308b (belongs_to) \u95a2\u9023\u4ed8\u3051
\napp\/models\/micropost.rb<\/strong><\/p>\n
class Micropost < ApplicationRecord<\/strong>\r\n  belongs_to :user<\/strong>\r\n  validates :user_id, presence: true<\/strong>\r\n  validates :content, presence: true, length: { maximum: 140 }<\/strong>\r\nend<\/strong><\/pre>\n
\u30e6\u30fc\u30b6\u30fc\u304c\u30de\u30a4\u30af\u30ed\u30dd\u30b9\u30c8\u3092\u8907\u6570\u6240\u6709\u3059\u308b (has_many) \u95a2\u9023\u4ed8\u3051 green
\napp\/models\/user.rb<\/strong><\/p>\n
#\u8ffd\u52a0\r\nhas_many :microposts<\/strong><\/pre>\n
\u6163\u7fd2\u7684\u306b\u6b63\u3057\u304f\u30de\u30a4\u30af\u30ed\u30dd\u30b9\u30c8\u3092\u4f5c\u6210\u3059\u308b green
\ntest\/models\/micropost_test.rb<\/strong><\/p>\n
require<\/span> 'test_helper'<\/span>\r\nclass<\/span> MicropostTest<\/span> <<\/span> ActiveSupport<\/span>::<\/span>TestCase<\/span>\r\n  def<\/span> setup<\/span>\r\n    @user<\/span> =<\/span> users<\/span>(<\/span>:michael<\/span>)<\/span>\r\n    @micropost<\/span> =<\/span> @user<\/span>.<\/span>microposts<\/span>.<\/span>build<\/span>(<\/span>content<\/span>:<\/span> \"Lorem ipsum\"<\/span>)<\/span>\r\n<\/span>  end<\/span>\r\n  test<\/span> \"should be valid\"<\/span> do<\/span>\r\n    assert<\/span> @micropost<\/span>.<\/span>valid?<\/span>\r\n  end<\/span>\r\n  test<\/span> \"user id should be present\"<\/span> do<\/span>\r\n    @micropost<\/span>.<\/span>user_id<\/span> =<\/span> nil<\/span>\r\n    assert_not<\/span> @micropost<\/span>.<\/span>valid?<\/span>\r\n  end<\/span>\r\n  .<\/span>\r\n  .<\/span>\r\n  .<\/span>\r\nend<\/span><\/strong><\/pre>\n
\u6f14\u7fd2<\/h3>\n
1:\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u306b\u3044\u308b\u6700\u521d\u306e\u30e6\u30fc\u30b6\u30fc\u3092\u5909\u6570user\u306b\u4ee3\u5165\u3057\u3066\u304f\u3060\u3055\u3044\u3002\u305d\u306euser\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u3092\u4f7f\u3063\u3066micropost = user.microposts.create(content: “Lorem ipsum”)\u3092\u5b9f\u884c\u3059\u308b\u3068\u3001\u3069\u306e\u3088\u3046\u306a\u7d50\u679c\u304c\u5f97\u3089\u308c\u308b\u3067\u3057\u3087\u3046\u304b?<\/p>\n
micropost = user.microposts.create(content: \"Lorem ipsum\")<\/strong>\r\n\r\nSQL (6.6ms) INSERT INTO \"microposts\" (\"content\", \"user_id\", \"created_at\", \"updated_at\") VALUES (?, ?, ?, ?) [[\"content\", \"Lorem ipsum\"], [\"user_id\", 1], [\"created_at\", \"2020-04-10 00:33:04.704864\"], [\"updated_at\", \"2020-04-10 00:33:04.704864\"]]<\/strong>\r\n\r\n=> #<Micropost id: 1, content: \"Lorem ipsum\", user_id: 1, created_at: \"2020-04-10 00:33:04\", updated_at: \"2020-04-10 00:33:04\"><\/strong><\/pre>\n
2:\u5148\u307b\u3069\u306e\u6f14\u7fd2\u8ab2\u984c\u3067\u3001\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u4e0a\u306b\u65b0\u3057\u3044\u30de\u30a4\u30af\u30ed\u30dd\u30b9\u30c8\u304c\u8ffd\u52a0\u3055\u308c\u305f\u306f\u305a\u3067\u3059\u3002user.microposts.find(micropost.id)\u3092\u5b9f\u884c\u3057\u3066\u3001
\n\u672c\u5f53\u306b\u8ffd\u52a0\u3055\u308c\u305f\u306e\u304b\u3092\u78ba\u304b\u3081\u3066\u307f\u307e\u3057\u3087\u3046\u3002\u307e\u305f\u3001\u5148\u307b\u3069\u5b9f\u884c\u3057\u305f
\nmicropost.id\u306e\u90e8\u5206\u3092micropost\u306b\u5909\u66f4\u3059\u308b\u3068\u3001\u7d50\u679c\u306f\u3069\u3046\u306a\u308b\u3067\u3057\u3087\u3046\u304b?<\/p>\n
user.microposts.find(micropost.id)<\/strong>\r\nMicropost Load (0.2ms) SELECT \"microposts\".* FROM \"microposts\" WHERE \"microposts\".\"user_id\" = ? AND \"microposts\".\"id\" = ? LIMIT ? [[\"user_id\", 1], [\"id\", 1], [\"LIMIT\", 1]]<\/strong>\r\n\r\n=> #<Micropost id: 1, content: \"Lorem ipsum\", user_id: 1,<\/strong>\r\ncreated_at: \"2020-04-10 00:33:04\", updated_at: \"2020-04-10 00:33:04\"><\/strong>\r\n\r\nArgumentError (You are passing an instance of ActiveRecord::Base to `find`. Please pass the id of the object by calling `.id`.)<\/strong><\/pre>\n
3:user == micropost.user\u3092\u5b9f\u884c\u3057\u305f\u7d50\u679c\u306f\u3069\u3046\u306a\u308b\u3067\u3057\u3087\u3046\u304b?
\n\u307e\u305f\u3001user.microposts.first == micropost \u3092\u5b9f\u884c\u3057\u305f\u7d50\u679c\u306f
\n\u3069\u3046\u306a\u308b\u3067\u3057\u3087\u3046\u304b? \u305d\u308c\u305e\u308c\u78ba\u8a8d\u3057\u3066\u307f\u3066\u304f\u3060\u3055\u3044\u3002<\/p>\n
user == micropost.user<\/strong>\r\n=> true<\/strong>\r\n>> user.microposts.first == micropost<\/strong>\r\nMicropost Load (0.2ms) SELECT \"microposts\".* FROM \"microposts\" WHERE \"microposts\".\"user_id\" = ? ORDER BY \"microposts\".\"id\" ASC LIMIT ? [[\"user_id\", 1], [\"LIMIT\", 1]]<\/strong>\r\n=> true<\/strong><\/pre>\n
13.1.4 \u30de\u30a4\u30af\u30ed\u30dd\u30b9\u30c8\u3092\u6539\u826f\u3059\u308b<\/h3>\n
\u30e6\u30fc\u30b6\u30fc\u306e\u30de\u30a4\u30af\u30ed\u30dd\u30b9\u30c8\u3092\u7279\u5b9a\u306e\u9806\u5e8f\u3067\u53d6\u5f97\u3067\u304d\u308b\u3088\u3046\u306b\u3057\u305f\u308a\u3001
\n\u30de\u30a4\u30af\u30ed\u30dd\u30b9\u30c8\u3092\u30e6\u30fc\u30b6\u30fc\u306b\u4f9d\u5b58\u3055\u305b\u3066\u3001\u30e6\u30fc\u30b6\u30fc\u304c\u524a\u9664\u3055\u308c\u305f\u3089\u30de\u30a4\u30af\u30ed\u30dd\u30b9\u30c8\u3082\u81ea\u52d5\u7684\u306b\u524a\u9664\u3055\u308c\u308b\u3088\u3046\u306b\u3057\u3066\u3044\u304d\u307e\u3059\u3002<\/p>\n
\u30c7\u30d5\u30a9\u30eb\u30c8\u306e\u30b9\u30b3\u30fc\u30d7<\/p>\n
user.microposts\u30e1\u30bd\u30c3\u30c9\u306f\u30c7\u30d5\u30a9\u30eb\u30c8\u3067\u306f\u8aad\u307f\u51fa\u3057\u306e\u9806\u5e8f\u306b\u5bfe\u3057\u3066\u4f55\u3082\u4fdd\u8a3c\u3057\u307e\u305b\u3093\u304c\u3001
\n\u6700\u3082\u65b0\u3057\u3044\u30de\u30a4\u30af\u30ed\u30dd\u30b9\u30c8\u3092\u6700\u521d\u306b\u8868\u793a\u3059\u308b\u3088\u3046\u306b\u3057\u3066\u307f\u307e\u3057\u3087\u3046\u3002
\n\u3053\u308c\u3092\u5b9f\u88c5\u3059\u308b\u305f\u3081\u306b\u306f\u3001default scope\u3068\u3044\u3046\u30c6\u30af\u30cb\u30c3\u30af\u3092\u4f7f\u3044\u307e\u3059\u3002<\/p>\n
\u307e\u305a\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u4e0a\u306e\u6700\u521d\u306e\u30de\u30a4\u30af\u30ed\u30dd\u30b9\u30c8\u304c\u3001
\nfixture\u5185\u306e\u30de\u30a4\u30af\u30ed\u30dd\u30b9\u30c8 (most_recent) \u3068\u540c\u3058\u3067\u3042\u308b\u304b\u691c\u8a3c\u3059\u308b\u30c6\u30b9\u30c8\u3092\u66f8\u3044\u3066\u3044\u304d\u307e\u3057\u3087\u3046\u3002<\/p>\n
\u30de\u30a4\u30af\u30ed\u30dd\u30b9\u30c8\u306e\u9806\u5e8f\u4ed8\u3051\u3092\u30c6\u30b9\u30c8\u3059\u308b red
\ntest\/models\/micropost_test.rb<\/strong><\/p>\n
require 'test_helper'<\/strong>\r\n\r\n  class MicropostTest < ActiveSupport::TestCase<\/strong>\r\n.<\/strong>\r\n.<\/strong>\r\n.<\/strong>\r\n  test \"order should be most recent first\" do<\/strong>\r\n  assert_equal microposts(:most_recent), Micropost.first<\/strong>\r\n end<\/strong>\r\nend<\/strong><\/pre>\n
\u30de\u30a4\u30af\u30ed\u30dd\u30b9\u30c8\u7528\u306efixture\r\ntest\/fixtures\/microposts.yml<\/strong>\r\n\r\norange:<\/strong>\r\ncontent: \"I just ate an orange!\"<\/strong>\r\ncreated_at: <%= 10.minutes.ago %><\/strong>\r\n\r\ntau_manifesto:<\/strong>\r\ncontent: \"Check out the @tauday site by @mhartl: http:\/\/tauday.com\"<\/strong>\r\ncreated_at: <%= 3.years.ago %><\/strong>\r\n\r\ncat_video:<\/strong>\r\ncontent: \"Sad cats are sad: http:\/\/youtu.be\/PKffm2uI4dk\"<\/strong>\r\ncreated_at: <%= 2.hours.ago %><\/strong>\r\n\r\nmost_recent:<\/strong>\r\ncontent: \"Writing a short test\"<\/strong>\r\ncreated_at: <%= Time.zone.now %><\/strong>\r\n\r\nStandardError: No fixture named 'most_recent' found for<\/strong>\r\nfixture set 'microposts'<\/strong><\/pre>\n
\u57cb\u3081\u8fbc\u307fRuby\u3092\u4f7f\u3063\u3066created_at\u30ab\u30e9\u30e0\u306b\u5024\u3092\u30bb\u30c3\u30c8\u3057\u3066\u3044\u308b\u70b9\u306b\u6ce8\u76ee\u3057\u3066\u304f\u3060\u3055\u3044
\n\u3053\u306e\u30ab\u30e9\u30e0\u306fRails\u306b\u3088\u3063\u3066\u81ea\u52d5\u7684\u306b\u66f4\u65b0\u3055\u308c\u308b\u305f\u3081\u57fa\u672c\u7684\u306b\u306f\u624b\u52d5\u3067\u66f4\u65b0\u3067\u304d\u306a\u3044\u306e\u3067\u3059\u304c\u3001fixture\u30d5\u30a1\u30a4\u30eb\u306e\u4e2d\u3067\u306f\u66f4\u65b0\u53ef\u80fd\u306b\u306a\u3063\u3066\u3044\u307e\u3059\u3002<\/p>\n
rails test<\/strong> test\/models\/micropost_test.rb<\/strong><\/pre>\n
\u6b21\u306b\u3001Rails\u306edefault_scope\u30e1\u30bd\u30c3\u30c9\u3092\u4f7f\u3063\u3066\u3053\u306e\u30c6\u30b9\u30c8\u3092\u6210\u529f\u3055\u305b\u307e\u3059\u3002
\n\u3053\u306e\u30e1\u30bd\u30c3\u30c9\u306f\u3001\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u304b\u3089\u8981\u7d20\u3092\u53d6\u5f97\u3057\u305f\u3068\u304d\u306e\u3001
\n\u30c7\u30d5\u30a9\u30eb\u30c8\u306e\u9806\u5e8f\u3092\u6307\u5b9a\u3059\u308b\u30e1\u30bd\u30c3\u30c9\u3067\u3059\u3002\u7279\u5b9a\u306e\u9806\u5e8f\u306b\u3057\u305f\u3044\u5834\u5408
\n\u306f\u3001default_scope\u306e\u5f15\u6570\u306border\u3092\u4e0e\u3048\u307e\u3059\u3002
\n\u4f8b\u3048\u3070\u3001created_at\u30ab\u30e9\u30e0\u306e\u9806\u306b\u3057\u305f\u3044\u5834\u5408\u306f\u6b21\u306e\u3088\u3046\u306b\u306a\u308a\u307e\u3059\u3002<\/p>\n
default_scope\u3067\u30de\u30a4\u30af\u30ed\u30dd\u30b9\u30c8\u3092\u9806\u5e8f\u4ed8\u3051\u308b
\napp\/models\/micropost.rb<\/strong><\/p>\n
#\u8ffd\u52a0\r\ndefault_scope -> { order(created_at: :desc) }<\/strong><\/pre>\n
\u30e9\u30e0\u30c0\u5f0f (Stabby lambda) \u3068\u3044\u3046\u6587\u6cd5\u3092\u4f7f\u3063\u3066\u3044\u307e\u3059\u3002\u3053\u308c\u306f\u3001Proc\u3084lambda(\u3082\u3057\u304f\u306f\u7121\u540d\u95a2\u6570)\u3068\u547c\u3070\u308c\u308b\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u3092\u4f5c\u6210\u3059\u308b\u6587\u6cd5\u3067\u3059\u3002
\n->\u3068\u3044\u3046\u30e9\u30e0\u30c0\u5f0f\u306f\u3001\u30d6\u30ed\u30c3\u30af\u3092\u5f15\u6570\u306b\u53d6\u308a\u3001Proc\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u3092\u8fd4\u3057\u307e\u3059\u3002
\n\u3053\u306e\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u306f\u3001call\u30e1\u30bd\u30c3\u30c9\u304c\u547c\u3070\u308c\u305f\u3068\u304d\u3001
\n\u30d6\u30ed\u30c3\u30af\u5185\u306e\u51e6\u7406\u3092\u8a55\u4fa1\u3057\u307e\u3059\u3002\u3053\u306e\u69cb\u6587\u3092\u30b3\u30f3\u30bd\u30fc\u30eb\u3067\u78ba\u304b\u3081\u3066\u307f\u307e\u3057\u3087\u3046\u3002<\/p>\n
-> { puts \"foo\" }<\/strong>\r\n=> #<Proc:0x007fab938d0108@(irb):1 (lambda)><\/strong>\r\n>> -> { puts \"foo\" }.call<\/strong>\r\nfoo<\/strong>\r\n=> nil<\/strong><\/pre>\n
green<\/strong><\/span><\/span><\/div>\n
\n
\n
rails test<\/strong><\/pre>\n<\/div>\n<\/div>\n
\u30e6\u30fc\u30b6\u30fc\u304c\u524a\u9664\u3055\u308c\u305f\u5834\u5408\u3001\u30e6\u30fc\u30b6\u30fc\u306e\u30de\u30a4\u30af\u30ed\u30dd\u30b9\u30c8\u3082\u540c\u69d8\u306b\u524a\u9664\u3055\u308c\u308b\u3079\u304d\u3067\u3059\u3002<\/p>\n
\u3053\u306e\u632f\u308b\u821e\u3044\u306f\u3001has_many\u30e1\u30bd\u30c3\u30c9\u306b\u30aa\u30d7\u30b7\u30e7\u30f3\u3092\u6e21\u3057\u3066\u3042\u3052\u308b\u3053\u3068\u3067\u5b9f\u88c5\u3067\u304d\u307e\u3059<\/p>\n
\u30de\u30a4\u30af\u30ed\u30dd\u30b9\u30c8\u306f\u3001\u305d\u306e\u6240\u6709\u8005 (\u30e6\u30fc\u30b6\u30fc) \u3068\u4e00\u7dd2\u306b\u7834\u68c4\u3055\u308c\u308b\u3053\u3068\u3092\u4fdd\u8a3c\u3059\u308b
\napp\/models\/user.rb<\/strong><\/p>\n
class User < ApplicationRecord<\/strong>\r\nhas_many :microposts, dependent: :destroy<\/strong><\/pre>\n
dependent: :destroy\u3068\u3044\u3046\u30aa\u30d7\u30b7\u30e7\u30f3\u3092\u4f7f\u3046\u3068\u3001
\n\u30e6\u30fc\u30b6\u30fc\u304c\u524a\u9664\u3055\u308c\u305f\u3068\u304d\u306b\u3001\u305d\u306e\u30e6\u30fc\u30b6\u30fc\u306b\u7d10\u4ed8\u3044\u305f
\n(\u305d\u306e\u30e6\u30fc\u30b6\u30fc\u304c\u6295\u7a3f\u3057\u305f)\u30de\u30a4\u30af\u30ed\u30dd\u30b9\u30c8\u3082\u4e00\u7dd2\u306b\u524a\u9664\u3055\u308c\u308b\u3088\u3046\u306b\u306a\u308a\u307e\u3059<\/p>\n
dependent: :destroy\u306e\u30c6\u30b9\u30c8 green
\ntest\/models\/user_test.rb<\/strong><\/p>\n
require<\/span> 'test_helper'<\/span>\r\n\r\nclass<\/span> UserTest<\/span> <<\/span> ActiveSupport<\/span>::<\/span>TestCase<\/span>\r\n\r\n  def<\/span> setup<\/span>\r\n    @user<\/span> =<\/span> User<\/span>.<\/span>new<\/span>(<\/span>name<\/span>:<\/span> \"Example User\"<\/span>,<\/span> email<\/span>:<\/span> \"user@example.com\"<\/span>,<\/span>\r\n                     password<\/span>:<\/span> \"foobar\"<\/span>,<\/span> password_confirmation<\/span>:<\/span> \"foobar\"<\/span>)<\/span>\r\n  end<\/span>\r\n  .<\/span>\r\n  .<\/span>\r\n  .<\/span>\r\n  test<\/span> \"associated microposts should be destroyed\"<\/span> do<\/span>\r\n    @user<\/span>.<\/span>save<\/span>\r\n    @user<\/span>.<\/span>microposts<\/span>.<\/span>create!<\/span>(<\/span>content<\/span>:<\/span> \"Lorem ipsum\"<\/span>)<\/span>\r\n    assert_difference<\/span> 'Micropost.count'<\/span>,<\/span> -<\/span>1<\/span> do<\/span>\r\n      @user<\/span>.<\/span>destroy<\/span>\r\n    end<\/span>\r\n  end<\/span>\r\nend<\/span><\/strong><\/pre>\n
\u6f14\u7fd2<\/h3>\n
1:Micropost.first.created_at\u306e\u5b9f\u884c\u7d50\u679c\u3068\u3001Micropost.last.created_at\u306e\u5b9f\u884c\u7d50\u679c\u3092\u6bd4\u3079\u3066\u307f\u307e\u3057\u3087\u3046\u3002<\/p>\n
Micropost.first.created_at<\/strong>\r\nMicropost Load (0.2ms) SELECT \"microposts\".* FROM \"microposts\" ORDER BY \"microposts\".\"id\" ASC LIMIT ? [[\"LIMIT\", 1]]<\/strong>\r\n=> Tue, 29 Jan 2019 07:36:23 UTC +00:00<\/strong>\r\n\r\nMicropost.last.created_at<\/strong>\r\nMicropost Load (0.2ms) SELECT \"microposts\".* FROM \"microposts\" ORDER BY \"microposts\".\"id\" DESC LIMIT ? [[\"LIMIT\", 1]]<\/strong>\r\n=> Fri, 10 Apr 2020 00:33:04 UTC +00:00<\/strong><\/pre>\n
2:Micropost.first\u3092\u5b9f\u884c\u3057\u305f\u3068\u304d\u306b\u767a\u884c\u3055\u308c\u308bSQL\u6587\u306f\u3069\u3046\u306a\u3063\u3066\u3044\u308b\u3067\u3057\u3087\u3046\u304b? \u540c\u69d8\u306b\u3057\u3066\u3001Micropost.last\u306e\u5834\u5408\u306f\u3069\u3046\u306a\u3063\u3066\u3044\u308b\u3067\u3057\u3087\u3046\u304b?
\n\u305d\u308c\u305e\u308c\u3092\u30b3\u30f3\u30bd\u30fc\u30eb\u4e0a\u3067\u5b9f\u884c\u3057\u305f\u3068\u304d\u306b\u8868\u793a\u3055\u308c\u308b\u6587\u5b57\u5217\u304c\u3001SQL\u6587\u306b\u306a\u308a\u307e\u3059\u3002<\/p>\n
Micropost.first<\/strong>\r\nMicropost Load (0.2ms) SELECT \"microposts\".* FROM \"microposts\" ORDER BY \"microposts\".\"created_at\" DESC LIMIT ? [[\"LIMIT\", 1]]<\/strong>\r\n=> #<Micropost id: 2, content: \"test\", user_id: 2, created_at: \"2020-04-10 01:43:31\", updated_at: \"2021-04-10 01:43:31\"><\/strong>\r\n\r\nMicropost.last<\/strong>\r\nMicropost Load (0.2ms) SELECT \"microposts\".* FROM \"microposts\" ORDER BY \"microposts\".\"created_at\" ASC LIMIT ? [[\"LIMIT\", 1]]<\/strong>\r\n=> #<Micropost id: 1, content: \"Lorem ipsum\", user_id: 1, created_at: \"2020-04-10 00:33:04\", updated_at: \"2021-04-10 00:33:04\"><\/strong><\/pre>\n
first\u306fDesk\u964d\u9806\u3067\u53d6\u308a\u51fa\u3057\u3066last\u306fASC\u6607\u9806\u3067\u53d6\u308a\u51fa\u3057\u3066\u3044\u308b\u3002<\/p>\n
3:\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u4e0a\u306e\u6700\u521d\u306e\u30e6\u30fc\u30b6\u30fc\u3092\u5909\u6570user\u306b\u4ee3\u5165\u3057\u3066\u304f\u3060\u3055\u3044\u3002
\n\u305d\u306euser\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u304c\u6700\u521d\u306b\u6295\u7a3f\u3057\u305f\u30de\u30a4\u30af\u30ed\u30dd\u30b9\u30c8\u306eid\u306f
\n\u3044\u304f\u3064\u3067\u3057\u3087\u3046\u304b?
\n\u6b21\u306b\u3001destroy\u30e1\u30bd\u30c3\u30c9\u3092\u4f7f\u3063\u3066\u305d\u306euser\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u3092\u524a\u9664\u3057\u3066\u307f\u3066\u304f\u3060\u3055\u3044\u3002\u524a\u9664\u3059\u308b\u3068\u3001\u305d\u306euser\u306b\u7d10\u4ed8\u3044\u3066\u3044\u305f
\n\u30de\u30a4\u30af\u30ed\u30dd\u30b9\u30c8\u3082\u524a\u9664\u3055\u308c\u3066\u3044\u308b\u3053\u3068\u3092
\nMicropost.find\u3067\u78ba\u8a8d\u3057\u3066\u307f\u307e\u3057\u3087\u3046<\/p>\n
>> user = User.first<\/strong>\r\nUser Load (0.1ms) SELECT \"users\".* FROM \"users\" ORDER BY \"users\".\"id\" ASC LIMIT ? [[\"LIMIT\", 1]]<\/strong>\r\n=> #<User id: 1, name: \"YUUKI\", email: \"yuukitetsuyanet@gmail.com\", created_at: \"2019-01-27 11:45:56\", updated_at: \"2019-01-28 10:06:18\", password_digest: \"$2a$10$RtF8nSd22GLENhTmlBTkPeaqyv7f3UeR6UecG...\", remember_digest: nil, admin: false, \u00a5: nil, activation_digest: \"$2a$10$f3kgl8ZWwRuixqBNDohcb.qkPwxw1Pq16gM...\", activated: true, activated_at: \"2019-01-27 11:46:05\", reset_digest: \"$2a$10$cs997A4KK0w9hg6cv82z0gw06pZOzIX3x\/p...\", reset_sent_at: \"2019-01-28 10:05:13\"><\/strong>\r\n>> user.microposts.first<\/strong>\r\nMicropost Load (0.1ms) SELECT \"microposts\".* FROM \"microposts\" WHERE \"microposts\".\"user_id\" = ? ORDER BY \"microposts\".\"id\" ASC LIMIT ? [[\"user_id\", 1], [\"LIMIT\", 1]]<\/strong>\r\n=> #<Micropost id: 1, content: \"Lorem ipsum\", user_id: 1, created_at: \"2019-01-29 07:36:23\", updated_at: \"2019-01-29 07:36:23\">\r\n>> user_f = user.microposts.first<\/strong>\r\nMicropost Load (0.1ms) SELECT \"microposts\".* FROM \"microposts\" WHERE \"microposts\".\"user_id\" = ? ORDER BY \"microposts\".\"id\" ASC LIMIT ? [[\"user_id\", 1], [\"LIMIT\", 1]]<\/strong>\r\n=> #<Micropost id: 1, content: \"Lorem ipsum\", user_id: 1, created_at: \"2019-01-29 07:36:23\", updated_at: \"2019-01-29 07:36:23\"><\/strong>\r\n>> user_f.destroy<\/strong>\r\n(0.1ms) begin transaction<\/strong>\r\nSQL (2.2ms) DELETE FROM \"microposts\" WHERE \"microposts\".\"id\" = ? [[\"id\", 1]]<\/strong>\r\n(6.1ms) commit transaction<\/strong>\r\n=> #<Micropost id: 1, content: \"Lorem ipsum\", user_id: 1, created_at: \"2019-01-29 07:36:23\", updated_at: \"2019-01-29 07:36:23\">>> Micropost.find(1)<\/strong>\r\nMicropost Load (0.2ms) SELECT \"microposts\".* FROM \"microposts\" WHERE \"microposts\".\"id\" = ? LIMIT ? [[\"id\", 1], [\"LIMIT\", 1]]<\/strong>\r\nActiveRecord::RecordNotFound: Couldn't find Micropost with 'id'=1<\/strong>\r\nfrom (irb):37<\/strong><\/pre>\n
13.2\u306b\u7d9a\u304f<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"
\u305d\u306e12\u304b\u3089\u7d9a\u304f \u7b2c13\u7ae0\u30e6\u30fc\u30b6\u30fc\u306e\u30de\u30a4\u30af\u30ed\u30dd\u30b9\u30c8 \u30e6\u30fc\u30b6\u30fc\u3068\u3044\u3046\u30ea\u30bd\u30fc\u30b9\u3060\u3051\u304c\u3001 Active Record\u306b\u3088\u3063\u3066\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u4e0a\u306e\u30c6\u30fc\u30d6\u30eb\u3068\u7d10\u4ed8\u3044\u3066\u3044\u307e\u3059\u3002 \u5168\u3066\u306e\u6e96\u5099\u304c\u6574\u3063\u305f\u4eca\u3001 \u30e6\u30fc\u30b6\u30fc\u304c\u77ed\u3044\u30e1\u30c3\u30bb\u30fc\u30b8\u3092\u6295\u7a3f\u3067\u304d […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"footnotes":""},"categories":[27,13],"tags":[],"class_list":["post-2953","post","type-post","status-publish","format-standard","hentry","category-programming-note","category-rails"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/suzutukiblog.com\/index.php\/wp-json\/wp\/v2\/posts\/2953","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/suzutukiblog.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/suzutukiblog.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/suzutukiblog.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/suzutukiblog.com\/index.php\/wp-json\/wp\/v2\/comments?post=2953"}],"version-history":[{"count":12,"href":"https:\/\/suzutukiblog.com\/index.php\/wp-json\/wp\/v2\/posts\/2953\/revisions"}],"predecessor-version":[{"id":4586,"href":"https:\/\/suzutukiblog.com\/index.php\/wp-json\/wp\/v2\/posts\/2953\/revisions\/4586"}],"wp:attachment":[{"href":"https:\/\/suzutukiblog.com\/index.php\/wp-json\/wp\/v2\/media?parent=2953"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/suzutukiblog.com\/index.php\/wp-json\/wp\/v2\/categories?post=2953"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/suzutukiblog.com\/index.php\/wp-json\/wp\/v2\/tags?post=2953"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}