getting Readable { .. } instead of specific collection using find() on mongodb - mongodb

Question

I have a collection named 'EloVars' on my mongodb, with only one document:
{
"_id": {
"$oid": "5800f3bfdcba0f48d2c58161"
},
"nextPID": "0",
"TotalComprasions": "0"
}
I'm trying to get the value of nextPID this way:
var myDoc = db.collection('EloVars').find();
if(myDoc) {
console.log('What exactly am I getting here:')
console.log(myDoc)
req.body.pid = myDoc.nextPID;
}
When I look at the console i noticed that what I'm getting is not 'EloVars' collection... just weired long Readable:
Readable {
pool: null,
server: null,
disconnectHandler:
{ s: { storedOps: [], storeOptions: [Object], topology: [Object] },
length: [Getter] },
bson: {},
ns: 'mydb.EloVars',
cmd:
{ find: 'mydb.EloVars',
limit: 0,
skip: 0,
query: {},
slaveOk: true,
readPreference: { preference: 'primary', tags: undefined, options: [Object] } },
options:
.....
.....
What is this readable and why am I getting it?

Answer 1

find() returns a cursor. You have to iterate the cursor to get the documents.
var cursor = db.collection('EloVars').find();
cursor.each(function(err, doc) {
console.log(doc);
});
Or you can convert it to an array to get the documents.
cursor.toArray(function(err, doc){
console.log(doc);
});

Answer 2

Why are you trying in this way? if there is not any specific reason and you just wanted to get "nextPID" the you can use below query:
db.collection('EloVars').findOne({},{_id:0, nextPID:1}).exec(function(err, doc) {
if(doc) {
console.log('What exactly am I getting here:')
console.log(myDoc)
req.body.pid = doc.nextPID;
}
})
P.S.: it'll get only one nextPID.
to get all:
db.collection('EloVars').find({},{_id:0, nextPID:1}).exec(function(err, docs) {
if(docs && docs.length){
// your code here
}
})