How many distinct jobs do the people have?
select count(distinct job) from person
What are these jobs?
select distinct job from person
List the names of all students.
select name from person where job = 'student'
What is the maximum age of students?
select max(age) from person where job = 'student'
Print the name of the student with this age.
select name from person where job = 'student' and age = (select max(age) from person where job = 'student' )