Average total country medals by region
Layered calculations are when you create a basic query with an aggregation, then reference that query as a subquery to run an additional calculation. This approach allows you to run aggregations on aggregations, such as a MAX()
of a COUNT()
or an AVG()
of a SUM()
.
In this exercise, your task is to pull the average total_golds
for all countries within each region. This report will apply only for summer events.
To avoid having to deal with null handling, we have created a summer_games_clean
table. Please use this when building the report.
This exercise is part of the course
Reporting in SQL
Hands-on interactive exercise
Have a go at this exercise by completing this sample code.
-- Query total_golds by region and country_id
SELECT
____,
____,
____ AS total_golds
FROM ____ AS s
JOIN ____ AS c
ON ____
GROUP BY ____;