Show me the name of customers.
select first_name, last_name from customers
What about their coupon amounts?
select t1.first_name, t1.last_name, t2.coupon_amount from customers as t1 join discount_coupons as t2 on t1.coupon_id = t2.coupon_id
Show me those with amount 500.
select t1.first_name, t1.last_name, t2.coupon_amount from customers as t1 join discount_coupons as t2 on t1.coupon_id = t2.coupon_id where t2.coupon_amount = 500
Show me if they are bad or good.
select t1.good_or_bad_customer from customers as t1 join discount_coupons as t2 on t1.coupon_id = t2.coupon_id where t2.coupon_amount = 500