I am using MongoDB for a discord bot I am working on, and I want to retrieve a user's balance. My current code is function findBalance(id){ MongoClient.connect(url, function(err, db) { if (err) throw err; var dbo = db.db("DiscordDB"); var query = { uuid: id }; dbo.collection("players").find(query).toArray(function(err, result) { if (err) throw err; console.log(result.balance); db.close(); }); }); }. When I call the function it returns undefined... any thoughts?


Note the db.collection("players").find(query).toArray() returns an array of documents - these are available as result array. Your code console.log(result.balance) returned undefined - as you are looking for a property called balance in the array. You could do that on an object (or document) which has a property with that name - not on the array.

Retrieve an individual property from an array of objects - do the following to print each document's balance property value:

result.forEach(doc => console.log(doc.balance));

Here is your function's code in a slightly different way:

const MongoClient = require('mongodb').MongoClient;
const url = 'mongodb://localhost:27017';

MongoClient.connect(url, { useUnifiedTopology: true }, function(err, client) {
    if (err) throw err;
    console.log("Connected successfully to server");
    const db = client.db("DiscordDB");
    const id = "some value"; // input value
    findBalance(db, id, function(result) {
        result.forEach(doc => console.log(doc.balance));
        console.log("Closing connection.");

const findBalance = function(db, id, callback) {
    const query = { uuid: id };
        .toArray(function(err, result) { 
            if (err) throw err; 
            console.log("Query ran okay");
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