Find largest document size in MongoDB

Question

Is it possible to find the largest document size in MongoDB?

db.collection.stats() shows average size, which is not really representative because in my

Answer 1

Note: this will attempt to store the whole result set in memory (from .toArray) . Careful on big data sets. Do not use in production! Abishek's answer has the advantage of working over a cursor instead of across an in memory array.

If you also want the _id, try this. Given a collection called "requests" :

// Creates a sorted list, then takes the max
db.requests.find().toArray().map(function(request) { return {size:Object.bsonsize(request), _id:request._id}; }).sort(function(a, b) { return a.size-b.size; }).pop();

// { "size" : 3333, "_id" : "someUniqueIdHere" }