THE CLOUD EXPEDITION! · Chapter 2
Crunching the Cloud
Dr. Velocity makes an early cameo, slamming open the door with a clipboard. Enough peeking at 10 rows — lets see what this cloud can REALLY do! She taps a chart showing migration routes across continents. Aggregate the ENTIRE global migrations table. No LIMIT. Let MotherDuck flex. Time for Cloud Aggregations — summarizing large cloud datasets with GROUP BY.
Your task
Which ponds send out the most migration flocks? Summarize by origin pond — show the <b>origin_pond</b>, flight count (<b>total_flights</b>), and average flock size rounded to 2 decimals (<b>avg_flock_size</b>). Busiest ponds first. Table: `dbquacks_cloud_expedition.global_migrations` (MotherDuck).
Hint
Remember ROUND for controlling decimal places in your averages
Expected result
Rows with origin_pond, total_flights, and avg_flock_size — one per pond, ordered by most flights
Tables
lake_visits (500 rows)
| column | type |
|---|---|
visit_id | BIGINT |
duck_id | BIGINT |
destination_pond | VARCHAR |
visit_date | DATE |
purpose | VARCHAR |
pondville_events (50 rows)
| column | type |
|---|---|
event_id | BIGINT |
event_name | VARCHAR |
event_date | DATE |
organizer_id | BIGINT |
location | VARCHAR |
attendee_count | BIGINT |
pondville_residents (100 rows)
| column | type |
|---|---|
duck_id | BIGINT |
name | VARCHAR |
species | VARCHAR |
home_pond | VARCHAR |
age | BIGINT |
occupation | VARCHAR |
joined_date | DATE |
dbquacks_cloud_expedition.global_migrations
A table in a MotherDuck share; its columns are not listed here.
Database: https://dbquacks.com/data/databases/motherduck_tutorial.duckdb
This page as markdown: https://dbquacks.com/motherduck/6.md