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Why is document.remove() not working in Mongoose, Node.js?

Problem: I try to delete a document from the database using document.remove() in the following codes, but it does not remove this document from database . I am confident remove() is called because the pre hook I set up for 'remove' is called.

// Delete - delete a player and update the team
router.delete("/:player_id", function(req, res) {
    Player.findById(req.params.player_id, function(err, foundPlayer) {
        if(err) {
            console.log(err);
            req.flash("error", "Player you want to delete is NOT FOUND!");
            res.redirect("back");
            return;
        }
        foundPlayer.remove(function(err, removedPlayer) {
            if(!err) {
                console.log(removedPlayer); // prints null
            }
        }); // <<<<<<<<<<<
        res.redirect("back");
    });
});

I then use model.findByIdAndRemove() in the following codes, and it worked.

// Delete - delete a player and update the team
router.delete("/:player_id", function(req, res) {
    Player.findByIdAndRemove(req.params.player_id, function(err, foundPlayer) {
        if(err) {
            console.log(err);
            req.flash("error", "Player you want to delete is NOT FOUND!");
            res.redirect("back");
            return;
        }
        res.redirect("back");
    });
});

I have two Schemas:

var TeamSchema = new mongoose.Schema({
    name: String,
    players: [
        {
            type: mongoose.Schema.ObjectId,
            ref: "Player"
        }
    ],
});

var PlayerSchema = new mongoose.Schema({
    name: String,
    team: {
        type: mongoose.Schema.Types.ObjectId,
        ref: "Team"
    }
});

Thank you so much in advance!

remove() has been deprecated, try this

Player.deleteOne(req.params.player_id,function(err, removedPlayer) {
            if(!err) {
                console.log(removedPlayer); // prints null
            }
        }); // <<<<<<<<<<<

You have used the .remove() on the foundPlayer which was returned by the findByID . You should use the remove directly on the model from which you are trying to remove the document. For eg. The following would work -

Player.remove({_id:req.params.player_id},function(err, foundPlayer){
    if(!err)
        console.log(foundPlayer);
});

If the player with given _id has been found you will get something logged onto the console like this -

deleted
{ n: 1, ok: 1, deletedCount: 1 }


NOTE:

Trying to use remove() will probably give you an warning saying -

DeprecationWarning: collection.remove is deprecated. Use deleteOne, deleteMany, or bulkWrite instead.

So, you must use deleteOne or deleteMany instead according to your requirement. So your code should be like this -

Player.deleteOne({_id:req.params.player_id},function(err, foundPlayer){
    if(!err)
        console.log(foundPlayer);
});

You can also choose to use the following if you want to use the foundPlayer doucment itself to be used in callback -

  • findOneAndDelete() / findByIdAndDelete() : Finds a matching document, removes it, passing the found document (if any) to the callback. Executes immediately if callback is passed, else a Query object is returned.

Hope this helps !

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