Who are the customers that had more than 1 policy? List the customer details and id.
SELECT T1.customer_details ,  T1.customer_id FROM Customers AS T1 JOIN Customer_Policies AS T2 ON T1.Customer_id  =  T2.Customer_id GROUP BY T1.customer_id HAVING count(*)  >  1
customers that had more than 1 policy refers to HAVING COUNT(T2.policy_id) > 1; list the customer details and id refers to SELECT T1.customer_details, T1.customer_id;