CREATE TABLE Student (StuID VARCHAR2, advisor VARCHAR2)
CREATE TABLE Faculty (FacID VARCHAR2, rank VARCHAR2)

Show the ids of students whose advisors are professors.
SELECT T2.StuID FROM Faculty AS T1 JOIN Student AS T2 ON T1.FacID = T2.advisor WHERE T1.rank = "Professor"
SELECT "T2"."StuID" FROM "Faculty" "T1" JOIN "Student" "T2" ON "T1"."FacID" = "T2"."advisor" WHERE "Professor" = "T1"."rank"