191-5 Guided Project: Answering Business Questions using SQL Activity 5

Because there are a number of countries with only one customer, you should group these customers as “Other” in your analysis. How do you use a CASE statement to fulfill this criteria.

I’ve tried:

        WHEN (SELECT COUNT(country) FROM customer)=1 THEN 'Other'
        ELSE country
    END country
    FROM customer

The problem with this is that it turns all of the countries into Other. However, I only want the countries that appear once to be grouped in Other.