Question

我正在Lynda.com上学习一门课程（Ruby on Rails 5基本培训）。这和Can't insert MySQL query in Rails 5 (Lynda Course)几乎是相同的问题。

我与Rich-to-Many关联有问题。当我写此行时出现错误：

section = Section.create(:name => 'Section One', :position => 1)

错误是：

(0.3ms)  BEGIN
(0.3ms)  ROLLBACK
=> #<Section id: nil, page_id: nil, name: "Section One", position: 1, visible: false, content_type: nil, content: nil, created_at: nil, updated_at: nil>

我正在学习这门课程。

Migrate.rb看起来像这样：

class CreateSectionEdits < ActiveRecord::Migration[5.2]
  def up
    create_table :section_edits do |t|
      t.integer "admin_user_id"
      t.integer "section_id"
      t.string "summary"
      t.timestamps
    end
    add_index("section_edits", ["admin_user_id", "section_id"])
  end

  def down
    drop_table :section_edits
  end
end

Sectionedit.rb看起来像这样：

class SectionEdit < ApplicationRecord
  belongs_to :admin_users, optional: true  
  belongs_to :section
end

admin_user.rb看起来像这样：

class AdminUser < ApplicationRecord
  #self.table_name = "admin_users"
  has_and_belongs_to_many :pages
  has_many :section_edits
end

section.rb看起来像这样：

class Section < ApplicationRecord
  belongs_to :page, { :optional => false}
  has_many :section_edits
end

我的错误无法解决。请参阅。寻找帮助。

Answer 1

在您的Section模型中，您写了belongs_to :page, { :optional => false}，page不是可选的，因此您必须为page分配一个section

您可以执行以下操作：

page = Page.create(:field => 'something') # or page = Page.find(page_id), it depends on your app’s business logic
section = Section.create(:name => 'Section One', :position => 1, :page => page)

开始后进行MySQL查询回滚

1 个答案: