An aggregation, built and charted

What happens

Four stages added to the aggregation builder one at a time, each answered by its own Run to here: a $match, then a $lookup filled in by choosing the collection and the two fields to join on, then an $unwind whose preview opens to show the whole joined customer sitting inside an order, then a $group; the result is read as a bar chart of revenue by customer tier.

Chapters

1. 0:00 Open orders
2. 0:03 Switch to the builder
3. 0:06 More room to build in
4. 0:10 $match: only the orders that count
5. 0:21 $lookup: bring the customer in
6. 0:35 $unwind: one row per customer
7. 0:45 Open one of them
8. 0:48 And the whole customer came with it
9. 0:53 $group: revenue by customer tier
10. 1:10 Run the whole pipeline
11. 1:13 Drag the result open
12. 1:17 Read it as a chart instead
13. 1:19 Category breakdown
14. 1:28 The chart