How to change _id of collections in MeteorJS?

My collection is

This article shows how to modify collections _id:

db.status.find().forEach(function(doc){ 
    doc._id=doc.UserId; db.status_new.insert(doc);
});
db.status_new.renameCollection("status", true);

But is this how you would do it in MeteorJS, what if I dont have userID?

To answer the topics question - you can’t really change the _id of a document. You can create a copy of the document and assign a new _id to the new document (and optionally delete the old document)

The doc.UserId in the example is just a value of the document. You can assign any unique value to the _id you want. The example does not really change the _id – it creates a new document in a new collection and then renames the collection. I’m not sure this works and looks really dirty and I suggest you to use the accepted answer of that stackoverflow question:

// store the document in a variable
doc = db.clients.findOne({_id: ObjectId("4cc45467c55f4d2d2a000002")})

// set a new _id on the document
doc._id = ObjectId("4c8a331bda76c559ef000004")

// insert the document, using the new _id
db.clients.insert(doc)

// remove the document with the old _id
db.clients.remove({_id: ObjectId("4cc45467c55f4d2d2a000002")})

Hi Rihards,

I am generating a new collections on the fly so it needs to be in a loop. Also, why would the accepted answer be correct when the id are hardcoded and not for a loop? Could you modify the accepted answer but for a loop and not using hardcoded IDs? Thanks