如何在rails应用程序中将模型与User模型相关联

Question

我的rails应用程序中有两个模型User和Event，但我的事件表中user_id始终为NULL

+----+------------+----------+-------------+---------------------+---------+
| id | date       | time     | venue       | created_at          | user_id |
+----+------------+----------+-------------+---------------------+---------+
|  1 | 0011-11-11 | 12:00:00 | ait pune    | 2015-09-18 11:16:51 |    NULL |
|  2 | 0011-11-11 | 12:00:00 | dighi hills | 2015-09-18 14:29:01 |    NULL |
|  3 | 0011-11-11 | 12:00:00 | obh         | 2015-09-18 14:32:41 |    NULL |
|  4 | 0011-11-11 | 12:00:00 | nbh         | 2015-09-18 14:46:40 |    NULL |
+----+------------+----------+-------------+---------------------+---------+

以下是我的架构

ActiveRecord::Schema.define(version: 20150918134819) do

  create_table "events", force: :cascade do |t|
    t.date     "date"
    t.time     "time"
    t.string   "venue",      limit: 255
    t.integer  "user_id",    limit: 4
  end

  create_table "users", force: :cascade do |t|
    t.string   "email",                  limit: 255, default: "", null: false
    t.string   "encrypted_password",     limit: 255, default: "", null: false
    end

  add_index "users", ["email"], name: "index_users_on_email", unique: true, using: :btree

end

用户和事件模型如下所示

class User < ActiveRecord::Base
  has_one :event, dependent: :destroy
end

class Event < ActiveRecord::Base
    belongs_to :user
end

我不知道我哪里出错了

Answer 1

应该是the has_many association：

class User < ActiveRecord::Base
  has_many :events, dependent: :destroy
end

class Event < ActiveRecord::Base
    belongs_to :user
end

<强>用法

arsen = User.create
arsen.events << Event.create

Event.create(user: arsen)

  

has_many关联表示与另一个的一对多连接   模型。你经常会在a的“另一面”找到这种关联   belongs_to association。此关联表示每个实例   该模型具有零个或多个另一个模型的实例。例如，   在包含客户和订单的应用程序中，客户模型   可以像这样声明：