Let your data do the math.

Build MongoDB 4.0 aggregation pipelines for summaries, grouping and transformations.

A first pipeline

const orders = BsonLite.collection('orders');

const totals = await orders.aggregate([
  { $match: { status: 'paid' } },
  { $group: {
    _id: '$category',
    revenue: { $sum: '$amount' },
    orders: { $sum: 1 }
  } },
  { $sort: { revenue: -1 } }
]).toArray();

aggregate returns a cursor. A pipeline processes documents through ordered stages. Filter early with $match when appropriate, and build indexes to support the initial query.

Common building blocks

Stage	Use
$match	Filter input documents
$project	Choose or calculate output fields
$group	Group and aggregate values
$sort / $limit	Order and bound results
$unwind	Process elements of an array
$lookup	Join supported local collections

Use the stages and expressions available in MongoDB 4.0.28. New server features do not become available by updating only the Node.js driver.

Disk use and encryption

const summary = await orders.aggregate([
  { $sort: { createdAt: -1 } },
  { $group: { _id: '$customerId', total: { $sum: '$amount' } } }
], { allowDiskUse: true }).toArray();

The full native Windows engine patches temporary-file encryption hooks. Real aggregation spill-file encryption is part of its native test suite. This does not turn the engine into an unlimited-memory system; allowDiskUse, workload size and disk capacity still matter.

Standalone profile

Replica-set transactions and change streams are not provided by this standalone deployment. Server-side JavaScript is disabled.

Documentation for BsonLite 0.6.0-rc.1. View SDK source · Download the validated SDK