[SQL문제풀기] New Products

문제

StrataScratch - New Products

StrataScratch

https://platform.stratascratch.com/coding/10318-new-products?code_type=3

내가 작성한 정답

MySQL, PostgreSQL,Oracle

select company_name, 
        count(case when year=2020 then product_name end) -
        count(case when year=2019 then product_name end)
from car_launches
group by company_name;