How many clubs does the student Eric Tai belong to?
select count ( distinct t1.clubname ) from club as t1 join member_of_club as t2 on t1.clubid = t2.clubid join student as t3 on t2.stuid = t3.stuid where t3.fname = "Eric" and t3.lname = "Tai"
How many other students belong in 0 clubs?
select count ( * ) from student where stuid not in ( select t3.stuid from club as t1 join member_of_club as t2 on t1.clubid = t2.clubid join student as t3 on t2.stuid = t3.stuid )
How many students belong to 1 club?
select count ( * ) from ( select stuid from member_of_club group by stuid having count ( * ) = 1 )
What are their names?
select lname,fname from student where stuid in ( select stuid from member_of_club group by stuid having count ( * ) = 1 )
What are the club names of the clubs they belong to, please?
select clubname from club where clubid in ( select distinct clubid from member_of_club group by stuid having count ( * ) = 1 )