Random document from a collection in Mongoose

Question

I want to create a Schema.statics.random function that gets me a random element from the collection. I know there is an example for the native MongoDB driver, but I can't get it working in Mongoose.

Answer 1

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);     this.findOne().skip(rand).exec(callback);   }.bind(this)); }; 

Source: https://gist.github.com/3453567

NB I modified the code a bit to make it more readable.

Answer 2

If you are not wanting to add "test like" code into your schema, this uses Mongoose queries.

Model.count().exec(function(err, count){    var random = Math.floor(Math.random() * count);    Model.findOne().skip(random).exec(     function (err, result) {        // result is random     });  });