Use the query below to get a list of courses that have no student enrollments. This includes withdrawn/dropped enrollments and simply the absence of other active enrollments. It does not include the instructor account(s) as part of the count.
SELECT cm.course_id, cm.row_status
FROM course_main AS cm
INNER JOIN course_users AS cu ON
cm.pk1 = cu.crsmain_pk1
where cm.course_id LIKE '%SP2014'
GROUP BY cm.course_id, cm.row_status
HAVING SUM(CASE cu.role WHEN 'S' THEN 1 ELSE 0 END) -
SUM(CASE cu.role WHEN 'P' THEN 1 ELSE 0 END) = 0
order by cm.course_id asc