Question: What are the payment dates for any payments that have an amount greater than 10 or were handled by a staff member with the first name Elsa?
SQL: SELECT payment_date FROM payment WHERE amount  >  10 UNION SELECT T1.payment_date FROM payment AS T1 JOIN staff AS T2 ON T1.staff_id  =  T2.staff_id WHERE T2.first_name  =  'Elsa'