从 table 中移除 belongs_to 关系

Remove belongs_to relation from table

我想从定制礼服中删除 User belongs_to 关系 table。

这是我的定制装扮迁移:

class CreateCustomisedDresses < ActiveRecord::Migration
  def change
    create_table :customised_dresses do |t|
      t.belongs_to :user, index: true, null: :false
      t.timestamps null: false
    end
    add_foreign_key :customised_dresses, :users, dependent: :delete
end

我尝试了以下迁移,但它给了我一个错误:

class RemoveForeignKeyUsersFromCustomisedDresses < ActiveRecord::Migration
  def self.up
    add_foreign_key :customised_dresses, :users
  end
  def self.down
    remove_foreign_key :customised_dresses, :users
  end
end

你应该在 up 和 down 方法中交换你的代码:

class RemoveForeignKeyUsersFromCustomisedDresses < ActiveRecord::Migration
  def self.up
    remove_foreign_key :customised_dresses, :users
  end
  def self.down
    add_foreign_key :customised_dresses, :users
  end
end