CREATE TABLE COURSE (CName VARCHAR2, CID VARCHAR2)
CREATE TABLE ENROLLED_IN (CID VARCHAR2)

What are the name of courses that have at least five enrollments?
SELECT T1.CName FROM COURSE AS T1 JOIN ENROLLED_IN AS T2 ON T1.CID = T2.CID GROUP BY T2.CID HAVING COUNT(*) >= 5
SELECT "T1"."CName" FROM "COURSE" "T1" JOIN "ENROLLED_IN" "T2" ON "T1"."CID" = "T2"."CID" GROUP BY "T2"."CID" HAVING COUNT(*) >= 5