mongooseでの集計(aggregate , group , sum)

前提

• MongoDB Serverがローカルで動作している前提
• 動作確認環境
  • Windows10, VSCode
  • Node v8.11.3
  • "mongodb": "3.1.4",
  • "mongoose": "5.2.12",
• 参考
  • MongoDB で グループごと に データの合計値 を 集計する

サンプルソース

mongoose-aggregate.js

// Mongoose aggreagate の例
// <参考>
// https://garafu.blogspot.com/2018/01/mongodb-group-by-sum.html
require('../../config/config.js')
require("../../db/mongoose.js");
const {SampleOrder} = require("../../models/sampleorder.js")

//サンプルデータ定義
const orders =[
  { datetime: Date.parse("2017-12-15T12:00:00+09:00"), item: "pen", amount: 70 },
  { datetime: Date.parse("2017-12-15T12:00:00+09:00"), item: "note", amount: 40 },
  { datetime: Date.parse("2017-12-15T12:00:00+09:00"), item: "eraser", amount: 100 },
  { datetime: Date.parse("2017-12-12T12:00:00+09:00"), item: "note", amount: 80 },
  { datetime: Date.parse("2017-12-08T12:00:00+09:00"), item: "eraser", amount: 50 },
  { datetime: Date.parse("2017-11-21T12:00:00+09:00"), item: "eraser", amount: 70 },
  { datetime: Date.parse("2017-11-13T12:00:00+09:00"), item: "pen", amount: 20 },
  { datetime: Date.parse("2017-11-02T12:00:00+09:00"), item: "pen", amount: 40 },
  { datetime: Date.parse("2017-10-23T12:00:00+09:00"), item: "pen", amount: 30 },
  { datetime: Date.parse("2017-10-18T12:00:00+09:00"), item: "pen", amount: 10 },
]
//初期化
async function initSampleOrders(){
  await SampleOrder.deleteMany({})
  let res = await SampleOrder.insertMany(orders)
  console.log('[initSampleOrders] length:',res.length)
}
//集計
async function groupSum(){
  console.log('---method:',groupSum.name)
  const res = await SampleOrder.aggregate()
  .group({
    _id:'$item',
    total:{$sum:'$amount'},
  })
  console.log(res)
}
//Main
async function main() {
  console.log('*** start ***')
  await initSampleOrders()
  await groupSum()
  console.log('*** end ***')
}
main()

実行結果

*** start ***
[initSampleOrders] length: 10
---method: groupSum
[ { _id: 'note', total: 120 },
  { _id: 'eraser', total: 220 },
  { _id: 'pen', total: 170 } ]
*** end ***