Database: customers_and_invoices
Question: Show id, first name and last name for all customers and the number of accounts.
SQL:
SELECT T1.customer_id ,  T2.customer_first_name ,  T2.customer_last_name ,  count(*) FROM Accounts AS T1 JOIN Customers AS T2 ON T1.customer_id  =  T2.customer_id GROUP BY T1.customer_id