Database: customers_campaigns_ecommerce
Question: Show the names of customers who have at least 2 mailshots with outcome code 'Order'.
SQL:
SELECT T2.customer_name FROM mailshot_customers AS T1 JOIN customers AS T2 ON T1.customer_id  =  T2.customer_id WHERE outcome_code  =  'Order' GROUP BY T1.customer_id HAVING count(*)  >=  2