Question

我正在构建一个Rails 5.0应用程序。

在这个应用程序中，我有三个模型，用户，反馈和分配。

当用户将一个或多个接收者添加到他或她创建的Feedback对象时，会创建一个分配以保持此连接。

用户

User(id: integer, account_id: integer, fullname:string)

反馈

Feedback(id: integer, account_id: integer, user_id: integer, title: string, ftype: string, badge: string, category: string, privacy: string, anonymous: boolean, description: text, created_at: datetime, updated_at: datetime)

create_table "feedbacks", force: :cascade do |t|
    t.integer  "account_id"
    t.integer  "user_id"
    t.string   "title"
    t.string   "ftype",       default: "provided"
    t.string   "badge"
    t.string   "category"
    t.string   "privacy"
    t.boolean  "anonymous",   default: false
    t.text     "description"
    t.datetime "created_at",                       null: false
    t.datetime "updated_at",                       null: false
    t.index ["account_id"], name: "index_feedbacks_on_account_id", using: :btree
    t.index ["user_id"], name: "index_feedbacks_on_user_id", using: :btree
  end

分配

Assignment(id: integer, account_id: integer, user_id: integer, assignable_type: string, assignable_id: integer, created_at: datetime, updated_at: datetime) 

create_table "assignments", force: :cascade do |t|
    t.integer  "account_id"
    t.integer  "user_id"
    t.string   "assignable_type"
    t.integer  "assignable_id"
    t.datetime "created_at",      null: false
    t.datetime "updated_at",      null: false
    t.index ["account_id"], name: "index_assignments_on_account_id", using: :btree
    t.index ["assignable_type", "assignable_id"], name: "index_assignments_on_assignable_type_and_assignable_id", using: :btree
    t.index ["user_id"], name: "index_assignments_on_user_id", using: :btree
  end

如何获得反馈的前五位接收者？

Answer 1

您可以尝试定义每个用户拥有的分配数量：

Assignment.group(:user_id).count

它将返回哈希{1 => "10", 2 => "15", ...}

然后对它进行排序并提取前5个元素。

ids = Assignment.group(:user_id).count.sort_by{|_, v| -v}.first(5).map{|id, _| id}

它会返回适当用户的ID。

然后只需按ID找到用户。

users = User.where(id: ids)

如何让顶级用户从作业中获取

1 个答案: