Mongoose findbyid() return null

Question

I am trying to find a record in my mongo db by its id

No matter I use findbyid(), findone(id,...), it return null

here is my code. what is the solution?

Answer 1

Convert the string into ObjectId type before querying

var ObjectID = require('mongodb').ObjectID;   
async function updateData(id){
  const result = await Data.findById(new ObjectID(id));
  console.log(result);
}

refer: this answer.

Answer 2

Check your mongodb database, if _id is storaged as String, findById(id) can not found id. FindById(id) only finds ObjectId('yourId'). You might import database by using mongoimport and including _id in JSON, it's wrong, delete _id in imported JSON.

Answer 3

There is a simple solution to this:

Replace

const result = await Data.findById(id);

with

const result = await Data.findById(id).exec();

See Mongoose - What does the exec function do? for an explanation on what exec() does

Answer 4

I had the same problem. The _id in my DB collection was a String. After I enabled mongoose debug require('mongoose').set('debug', true), I found out that the mongoose query id as ObjectId("yourId") unless we define _id in the Schema. In order to solve the problem I had to add _id:String in to mongoose schema.

const MyDataSchema = new Schema({
  _id: String,
...
...
}

Answer 5

In my case, the imported file used to have the _id column as string, so it was messing the DB and I was no able to filter using that column.

Once I deleted the collection, removed the _id column from data file and re-imported it, the _id filtering started working fine.