Query specific fields of mongoDB using node.js

Question

In the code below the query gives me all the fields. I only want to query _id and serialno. How to go about it.

Schema

var DataSchema = new Schema({
  serialno: String,
  info: String,
  active: Boolean,
  content: String
});

Query

// Get list of datas
exports.index = function(req, res) {
  Data.find(function (err, data) {
    if(err) { return handleError(res, err); }
    return res.json(200, data);
  });
};

Answer 1

If you are using latest nodejs mongodb driver 3.0 or above try this code:

Data.find({}).project({ _id : 1, serialno : 1 }).toArray()