THE CLOUD EXPEDITION! · Chapter 7
Two Engines, One Query
Dr. Velocity revs two imaginary engines. Ladies and gentleducks, welcome to the DUAL EXECUTION DERBY! Your laptop and MotherDucks cloud, racing in PARALLEL! Captain Cloudsworth drops an imaginary checkered flag. But HOW does it decide what runs where? Lets peek under the hood. Discover Dual Execution — using EXPLAIN to see how MotherDuck splits work between local and cloud engines.
Your task
Peek under the hood of a hybrid query. Use `EXPLAIN` on a query that joins local `pondville_residents` with cloud `dbquacks_cloud_expedition.duck_travels` to see how MotherDuck splits work between your laptop and the cloud. Tables: `pondville_residents` (local), `dbquacks_cloud_expedition.duck_travels` (MotherDuck, linked by `duck_id`).
Hint
Prefix your query with EXPLAIN to see how DuckDB splits work between local and cloud
Expected result
An execution plan showing how MotherDuck splits the query between local and cloud operators
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.duck_travels
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/19.md