[코드카타] SQL 56 Investments in 2016

[코드카타] SQL 56 Investments in 2016

56. Investments in 2016
https://leetcode.com/problems/investments-in-2016/

Write a solution to report the sum of all total investment values 
in 2016 tiv_2016, for all policyholders who:
have the same tiv_2015 value as one or more other policyholders, and
are not located in the same city as any other policyholder 
(i.e., the (lat, lon) attribute pairs must be unique).
Round tiv_2016 to two decimal places.

select round(sum(tiv_2016),2) tiv_2016
from Insurance
where tiv_2015 in (
    select tiv_2015
    from Insurance
    group by tiv_2015
    having count(*) > 1
) and (lat, lon) in (
    select lat, lon
    from Insurance
    group by lat, lon
    having count(*) = 1
)

tiv_2015를 group by 후 tiv_2015 값이 1 초과인 값 구하기!
lat, lon를 group by 후 lat, lon 값이 1인 값 구하기!