SQL GUIDED PROJECT: Answering Business Questions Using SQL, PAGE 5

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My Code:

%%sql
WITH 
    countries AS
        (
         SELECT
            CASE
                WHEN (SELECT COUNT(*)
                      FROM customer
                      WHERE country = cus.country) = 1 THEN 'Other'
                ELSE cus.country
                END AS country_name,
            cus.customer_id,
            il.*
         FROM invoice_line AS il
         INNER JOIN invoice AS inv ON inv.invoice_id = il.invoice_id
         INNER JOIN customer AS cus ON cus.customer_id = inv.customer_id
            )

Hi, can somebody explain how does the CASE statement on the code above assigned the ‘Other’ to the countries. I’m really confuse. Thanks :slight_smile: