Show the first name and last name for all customers.
select customer_first_name, customer_last_name from customers
Also show their account names.
select t2.customer_first_name, t2.customer_last_name, t1.account_name from accounts as t1 join customers as t2 on t1.customer_id = t2.customer_id
Who has the account with name 900?
select t2.customer_first_name, t2.customer_last_name from accounts as t1 join customers as t2 on t1.customer_id = t2.customer_id where t1.account_name = "900"