Delete a key from a MongoDB document using Mongoose

Question

I\'m using the Mongoose Library for accessing MongoDB with node.js

Is there a way to remove a key from a document? i.e. not just set the value to n

Answer 1

You'll want to do this:

User.findOne({}, function(err, user){
  user.key_to_delete = undefined;
  user.save();
});

Answer 2

Try:

User.findOne({}, function(err, user){
  // user.key_to_delete = null; X
  `user.key_to_delete = undefined;`

  delete user.key_to_delete;

  user.save();
});

Answer 3

if you want to remove a key from collection try this method. this worked for me

 db.getCollection('myDatabaseTestCollectionName').update({"FieldToDelete": {$exists: true}}, {$unset:{"FieldToDelete":1}}, false, true);

Answer 4

At mongo syntax to delete some key you need do following:

{ $unset : { field : 1} }

Seems at Mongoose the same.

Edit

Check this example.

Answer 5

Mongoose document is NOT a plain javascript object and that's why you can't use delete operator.(Or unset from 'lodash' library).

Your options are to set doc.path = null || undefined or to use Document.toObject() method to turn mongoose doc to plain object and from there use it as usual. Read more in mongoose api-ref: http://mongoosejs.com/docs/api.html#document_Document-toObject

Example would look something like this:

User.findById(id, function(err, user) {
    if (err) return next(err);
    let userObject = user.toObject();
    // userObject is plain object
});

Answer 6

Could this be a side problem like using

function (user)

instead of

function(err, user)

for the find's callback ? Just trying to help with this as I already had the case.