我如何使用主动查询方法获得同样的结果？

Question

这就是我想要使用主动查询方法实现的目标我被要求不要进行数组迭代，而是使用主动查询方法来实现这个

         def index
            @measurements = current_user.measurements.with_units.created_on
            data = Hash.new { |h, k| h[k] = [] }
            @measurements.each do |m|
              data[m.unit.title] << m
            end
            render json: { data: data, status: :ok }
          end`

This is the image of the expected JSON i wish to achieve with Active query method 这是我的测量和单位模型

        class Measurement < ApplicationRecord
          belongs_to :user
          belongs_to :unit
          scope :with_units, -> { includes(:unit) }
          scope :created_on, -> { order('created_at DESC') }
        
          validates :value, presence: true
        end
        
        Model for Units
        class Unit < ApplicationRecord
          has_many :measurements
        
          scope :with_measurements, -> { includes(:measurements) }
          scope :with_user_id, ->(user) { where(user_id: user.id) }
        
          validates :title, presence: true
        end
    
    Schema table for measurements
    
      create_table "measurements", force: :cascade do |t|
        t.integer "unit_id"
        t.integer "user_id"
        t.float "value"
        t.datetime "created_at", precision: 6, null: false
        t.datetime "updated_at", precision: 6, null: false
      end
    
Schema table for Units 

      create_table "units", force: :cascade do |t|
        t.string "title"
        t.datetime "created_at", precision: 6, null: false
        t.datetime "updated_at", precision: 6, null: false
      end

Answer 1

使用as_json将ActiveRecord集合转换为json。

def index
  @measurements = current_user.measurements.with_units.created_on
  render json: { data: @measurements.as_json(include: :unit) , status: :ok }
end

我如何使用主动查询方法获得同样的结果？

how do i acheive this same result using Active Query Methods?

hash

activerecord

ruby-on-rails-3