PARTITION BY ORDER BY with Ranking
PARTITION BY ORDER BY with Window Frames
Using PARTITION BY ORDER BY with Analytical Functions
Instruction
Good job! Of course, other analytical functions can also work. Let's analyze another example:
SELECT Country, City, Rating, FIRST_VALUE(City) OVER(PARTITION BY Country ORDER BY Rating DESC) AS FirstCity FROM Store;
In the above query, we're showing each store individually and the city with the highest rating in that particular country. Note that this would be impossible without PARTITION BY – we couldn't get individual city names for each country separately.
Exercise
Show sales figures for August 1 to August 3. For each store, show the StoreId, the Day, the Revenue, and the date with the best revenue in that period (as BestRevenueDay).
Stuck? Here's a hint!
Use:
FIRST_VALUE(Day) OVER(PARTITION BY StoreId ORDER BY Revenue DESC)
