Mongoose positional operator errors

问题

I am trying to run a command like this in mongoose:

Song.update({url: s.url, "playlist.playlist_id": pl._id}, {$set: {"playlist.$.position": 505050}}, function(er, da) {
                                    console.log("song on playlist lets change position");
                                    console.log(er);
                                    console.log(da);
});

however I get the error: [TypeError: Cannot call method 'path' of undefined]

I am guessing it has to do with mongoose and $ operator because it works in the mongodb console.

Any ideas?

回答1:

I had similar issue with mongoose also, maybe edit your post to see the schema. I fixed my problem by doing the following modification in my schema:<

var Result = new Schema({

    id                : Number,
    detailResult   : [detailRef], 
    simpleResult   : [{id: ObjectId, unit: String, value: Number, completed: Boolean}]
});

Notice in the working example (below), I added new mongoose.Schema()

var Result = new Schema({

    id                : Number,
    detailResult   : [detailRef], 
    simpleResult   : [new mongoose.Schema({id: ObjectId, unit: String, value: Number, completed: Boolean})]
});

You probably need to do this modification to your playlist embeddedDoc parameter in your schema.

来源：https://stackoverflow.com/questions/8874617/mongoose-positional-operator-errors