SELECT name FROM instructor WHERE id NOT IN (SELECT id FROM teaches WHERE semester  =  'Spring')
Find the names of instructors who didn't each any courses in any Spring semester.
SELECT name FROM instructor WHERE id NOT IN ( SELECT id FROM teaches WHERE semester = 'Spring ' )
select name from instructor where id not in ( select id from teaches where semester = value )
Find the names of instructors who did n't each any courses in any Spring semester .