MongoDB - too much data for sort() with no index. Full collection

Question

MongoDB - too much data for sort() with no index. Full collection

I'm using Mongoose for Node.js to interface with the mongo driver, so my query looks like:

db.Deal
    .find({})
    .select({
        _id: 1,
        name: 1,
        opp: 1,
        dateUploaded: 1,
        status: 1
     })
     .sort({ dateUploaded: -1 })

And get: too much data for sort() with no index. add an index or specify a smaller limit

The number of documents in the Deal collection is quite small, maybe ~500 - but each one contains many embedded documents. The fields returned in the query above are all primitive, i.e. aren't documents.

I currently don't have any indexes setup other than the default ones - I've never had any issue until now. Should I try adding a compound key on:

{ _id: 1, name: 1, opp: 1, status: 1, dateUploaded: -1 }

Or is there a smarter way to perform the query? First time using mongodb.

node.js
mongodb

Answer 1

From the MongoDB documentation on limits and thresholds:

MongoDB will only return sorted results on fields without an index if the combined size of all documents in the sort operation, plus a small overhead, is less than 32 megabytes.

Probably all the embedded documents are too much, you should add an index on the sorted field dateUploaded if you want to run the same query.

Otherwise you can limit you query and start paginating the results.