Querying documents into one specific property in MongoDB

Question

I wanted to query all "doc" properties inside the "doc", like a nested. I guess you can understand further what I want to explain from the code below:

mongoose.connect("mongodb://127.0.0.1:27017/stationDB");

const docSchema = mongoose.Schema({
  naturka: String,
  address: String,
  coefficient: String,
  wheel: String,
  weight: Number
})

const stockSchema = mongoose.Schema({
  rollingStockNumber: String,
  docs: [docSchema]
});


const Doc = mongoose.model('Doc', docSchema);
const Stock = mongoose.model('Stock', stockSchema);

let doc;
  for(i=0; i<naturkaMinifiedArrayReady.length; i++){
    const doc = new Doc({
      naturka: naturkaMinifiedArrayReady[i],
      address: arrayOfWayPlanForm[i],
      coefficient: valueOfCarLength[i],
      wheel: numberOfWheels[i],
      weight: valueOfCarWeight[i]
    });
    docs = doc
  };

  const stock = new Stock({
    rollingStockNumber: rollingStock,
    docs: docs
  });
  stock.save((err) => {
    if (err) {
      res.redirect('/')
    }
  });

I have inserted 8 documents, but returning only the last document as you see:

{ _id: new ObjectId("62a1ac800d9d39966878ebb8"), rollingStockNumber: '922698012567076507200129101700057022060000000', docs: [ { naturka: '08 94331444 0271 030 72240 00300 0012 0 0 0 0 01/00 96 04 105 0200 OXP', address: 'Toshkent', coefficient: '1.05', wheel: '4', weight: 50, _id: new ObjectId("62a1ac800d9d39966878ebb7") } ], __v: 0 } 

Answer 1

The doc defined with let is an array, but you do =. If you add the data to the array with push, your problem will be solved.

let docs = [];
  for(i=0; i<naturkaMinifiedArrayReady.length; i++){
    const doc = new Doc({
      naturka: naturkaMinifiedArrayReady[i],
      address: arrayOfWayPlanForm[i],
      coefficient: valueOfCarLength[i],
      wheel: numberOfWheels[i],
      weight: valueOfCarWeight[i]
    });
    docs.push(doc)
  };