Solution 1:
Since you aren't interested in any data from gh simply use not exists
select grade, lastname, firstname, sid
from aspen a
where not exists (select * from gh where gh.sid = a.sid)
order by grade, lastname, firstname
SQL Query Duplicates Values
Solution 1:
Since you aren't interested in any data from gh simply use not exists
select grade, lastname, firstname, sid
from aspen a
where not exists (select * from gh where gh.sid = a.sid)
order by grade, lastname, firstname