sql - Redshift: Incremental products ordered across marketplaces

Question

I have a table, 'Customer_Orders' that basically lists the products purchased by customers across marketplaces (UK, DE, US etc). Here's a short overview of the table:

Cust_id	marketplace	product
1	UK	A
1	UK	B
1	DE	A
1	US	A
1	US	C

Answer 1

Are you trying to get the differences like this?

select cust_id, marketplace,
       (count(*) - max(case when marketplace = 'UK' then count(*) end) over (partition by cust_id)) as diff_from_uk
from Customer_Orders co
group by cust_id, marketplace;