How many appointments does each nurse have?
select count(*) from nurse as t1 join appointment as t2 on t1.employeeid = t2.prepnurse group by t1.employeeid
Find the nurse with the most appointments. What is the nurse's name?
select t1.name from nurse as t1 join appointment as t2 on t1.employeeid = t2.prepnurse group by t1.employeeid order by count(*) desc limit 1