Ruby on rails ActiveRecord:：上的InvalidForeignKey具有多个通过关系

当我试图通过ProjectUser模型销毁一个有很多用户的项目时，我遇到了以下错误

使用pgsql、rails 6.0.3、ruby 2.7

我不确定我在这个案子里遗漏了什么。谁能帮我照一下吗

这是完全错误：

ActiveRecord::InvalidForeignKey in ProjectsController#destroy

PG::ForeignKeyViolation: ERROR: update or delete on table "projects" violates foreign key constraint "fk_rails_1bf16ed5d0" on table "project_users" DETAIL: Key (id)=(8) is still referenced from table "project_users".

以下是我的模型、控制器和模式：

ActiveRecord::InvalidForeignKey in ProjectsController#destroy

PG::ForeignKeyViolation: ERROR: update or delete on table "projects" violates foreign key constraint "fk_rails_1bf16ed5d0" on table "project_users" DETAIL: Key (id)=(8) is still referenced from table "project_users".

projects\u controller.rb

def destroy
  @project.destroy
  redirect_to projects_url, notice: 'Project was successfully destroyed.'
end

project.rb

class Project < ApplicationRecord
  has_many :project_users
  has_many :users, through: :project_users
end

---

必须首先销毁与该项目关联的每个项目用户，然后销毁该项目

或者，您可以修改您的

has\u many

关系，并指定在销毁项目时，每个相关记录（不仅是项目用户，而且是所有用户）也将被销毁：

has_many :project_users, dependent: :destroy

---

谢谢你的快速回复！在

关联中添加
dependent:：destroy
会不会对用户或项目表数据造成任何伤害？它只会销毁相关的
project\u用户
，如果
project\u用户
也定义了
dependent:：destroy
关系，那么它将删除所有相关的记录。
create_table "project_users", force: :cascade do |t|
    t.bigint "user_id", null: false
    t.bigint "project_id", null: false
    t.datetime "created_at", precision: 6, null: false
    t.datetime "updated_at", precision: 6, null: false
    t.index ["project_id"], name: "index_project_users_on_project_id"
    t.index ["user_id"], name: "index_project_users_on_user_id"
end

has_many :project_users, dependent: :destroy