The db.collection.find method returns a cursor. The cursor.count() method on the cursor counts the number of documents referenced by a cursor. This is same as the db.collection.count(). Both these methods (the cursor.count() and db.collection.count()) are deprecated as of MongoDB v4.0. From the documentation: MongoDB drivers compatible with the 4.0 features deprecate their respective cursor and … Read more
Thanks to a github thread shared by Grégory NEUT in the question’s comments I have been able to establish certain facts: Mongoose’s populate() method does not use MongoDB’s $lookup behind the scenes. It simply makes another query to the database. Mongoose does not have functionalities that MongoDB does not have. populate() just makes two or … Read more
Actually, but for the fact that mongoose is actually “messing with” the update under the covers, this is actually the default action of your submission to a regular MongoDB function. So mongoose deems it “wise” as a convenience method to “presume” you meant to issue a $set instruction here. Since you actually do not want … Read more
you can do this now (with https://www.mongodb.com/blog/post/introducing-version-40-mongoose-nodejs-odm) var mongoose = require(‘mongoose’); // mongoose.Promise = require(‘bluebird’); // it should work with native Promise mongoose.connect(‘mongodb://……’); var NodeSchema = new mongoose.Schema({ children: [{type: mongoose.Schema.Types.ObjectId, ref: ‘Node’}], name: String }); var autoPopulateChildren = function(next) { this.populate(‘children’); next(); }; NodeSchema .pre(‘findOne’, autoPopulateChildren) .pre(‘find’, autoPopulateChildren) var Node = mongoose.model(‘Node’, NodeSchema) var … Read more
From the manual, the options argument needs a “fields” key in it since there are other details such as “upsert” and “new” where this applies. In your case you also want the “new” option: User.findOneAndUpdate( { “_id”: “132324” }, { “$set”: { “hair_color”: “yellow” } }, { “fields”: { “first_name”:1, “last_name”: 1 }, “new”: true … Read more
Mongoose interprets the object in the Schema with key ‘type’ in your schema as type definition for that object. deviceId: { type : String, index : { unique : true, dropDups : true } } So for this schema mongoose interprets deviceId as a String instead of Object and does not care about all other … Read more
To remove those properties from your existing doc, set them to undefined instead of null before saving the doc: user.first_name = undefined; user.signup_date = undefined; user.save(); Confirmed as still working in Mongoose 5.9.7. Note that the field you’re trying to remove must still be defined in your schema for this to work.
This is supported since Mongoose 4.5, and is called virtuals population. You have to define your foreign keys relationships after your schemas definitions and before creating models, like this: // Schema definitions BookSchema = new mongoose.Schema({ …, title: String, authorId: Number, … }, // schema options: Don’t forget this option // if you declare foreign … Read more
I found this Mongoose Schema static function in a GitHub Gist, which should achieve what you are after. It counts number of documents in the collection and then returns one document after skipping a random amount. QuoteSchema.statics.random = function(callback) { this.count(function(err, count) { if (err) { return callback(err); } var rand = Math.floor(Math.random() * count); … Read more
Sushant‘s answer is not correct. You need to be aware of NoSQL injection in MongoDB. Example (taken from here) User.findOne({ “name” : req.params.name, “password” : req.params.password }, callback); If req.params.password is { $ne: 1 }, the user will be retrieved without knowing the password ($ne means not equals 1). MongoDB Driver You can use mongo-sanitize: … Read more