Mongoose random object from a long list

Question

As Mongoose doesn't have an option for random find, which of the following is better to use? (less resource consuming)

Minimal query and then big query:

Page.find()
    .select('_id')
    .then(function(pages){
        var randomPage = _.sample(pages);
        Page.findOne({id: randomPage._id})
        .populate('comments')
        .then(function(page){...}
    }

One query and picking a random item:

Page.find()
    .populate('comments')
    .then(function(pages){
        var randomPage = _.sample(pages);
        ...
    }

Possible duplicate of [Random record from MongoDB](http://stackoverflow.com/questions/2824157/random-record-from-mongodb) — Hongbo Miao, Aug 14 '16 at 21:25

score 0 · Answer 1 · answered Aug 01 '16 at 13:03

0

Most efficient way is to use $sample operator in aggregation pipeline, which allowed since mongodb v3.2

DOCS: $sample (aggregation)

answered Aug 01 '16 at 13:03

evilive

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Mongoose random object from a long list

1 Answers1