Question

现在我有一个用户模型和一个博客模型。

class User < ApplicationRecord
  has_many :blogs, dependent: :destroy
end

class Blog < ApplicationRecord
  belongs_to :user
end

=> Blog(id: integer, user_id: integer, content: text, created_at: datetime, updated_at: datetime, title: string)

=> User(id: integer, name: string, email: string, username: string, number: integer, password_digest: string, created_at: datetime, updated_at: datetime, admin: boolean)

我曾经有一个播放器模型（与用户模型几乎相同，除了电子邮件/密码），但摆脱它。但是当我尝试在heroku控制台上创建一个新博客时，它给了我这个错误：

ActiveRecord::InvalidForeignKey: PG::ForeignKeyViolation: ERROR: insert or update on table "blogs" violates foreign key constraint "fk_rails_eb906800d1"DETAIL:  Key (user_id)=(13) is not present in table "players".

这是什么意思？

heroku日志

ActiveRecord::InvalidForeignKey (PG::ForeignKeyViolation: ERROR:  insert or update on table "blogs" violates foreign key constraint "fk_rails_eb906800d1"

DETAIL:  Key (user_id)=(13) is not present in table "players".


class CreateBlogs < ActiveRecord::Migration[5.0]
  def change
    create_table :blogs do |t|
      t.references :user, foreign_key: true
      t.text :content

      t.timestamps
    end
  end
end

class CreateUsers < ActiveRecord::Migration[5.0]
  def change
    create_table :users do |t|
      t.string :name
      t.string :email
      t.string :username
      t.integer :number
      t.string :password_digest

      t.timestamps
    end
  end
end


class AddAdminToUsers < ActiveRecord::Migration[5.0]
  def change
    add_column :users, :admin, :boolean, default: false
  end
end

class AddTitleToBlogs < ActiveRecord::Migration[5.0]
  def up
    add_column :blogs, :title, :string
  end

  def down
    remove_column :blogs, :title, :string
  end
end

rails heroku一对多外键

0 个答案: