Problem Description –
Write an SQL query to report the difference between the number of apples and oranges sold each day.
Return the result table ordered by sale_date
.
The query result format is in the following example.

Difficulty Level – Medium
Problem Link – Apples and Oranges
Solution –
SELECT
sale_date,
total_apples_sold - total_oranges_sold as diff
FROM (
SELECT
sale_date,
SUM(CASE WHEN fruit = 'apples' THEN sold_num ELSE 0 END) as total_apples_sold,
SUM(CASE WHEN fruit = 'oranges' THEN sold_num ELSE 0 END) as total_oranges_sold
FROM Sales
GROUP BY 1
) x
ORDER BY 1