List the customer status code with their respective counts.
select customer_status_code, count(*) from customers group by customer_status_code
Sort by ascending counts.
select customer_status_code, count(*) from customers group by customer_status_code order by count(*) asc
Which customer status code has least number of customers?
select customer_status_code from customers group by customer_status_code order by count(*) asc limit 1;