Running totals of athlete medals
The running total (or cumulative sum) of a column helps you determine what each row's contribution is to the total sum.
Deze oefening maakt deel uit van de cursus
PostgreSQL Summary Stats and Window Functions
Oefeninstructies
- Return the athletes, the number of medals they earned, and the medals running total, ordered by the athletes' names in alphabetical order.
Praktische interactieve oefening
Probeer deze oefening eens door deze voorbeeldcode in te vullen.
WITH Athlete_Medals AS (
SELECT
Athlete, COUNT(*) AS Medals
FROM Summer_Medals
WHERE
Country = 'USA' AND Medal = 'Gold'
AND Year >= 2000
GROUP BY Athlete)
SELECT
-- Calculate the running total of athlete medals
___,
___,
___ OVER (ORDER BY ___ ASC) AS Max_Medals
FROM Athlete_Medals
ORDER BY Athlete ASC;