① SELECT STUDENT.SNAME, ENROL.COURSE FROM ENROL INNER JOIN STUDENT ON ENROL.SNO = STUDENT.SNO; ② SELECT STUDENT.SNAME, ENROL.COURSE FROM STUDENT LEFT OUTER JOIN ENROL ON STUDENT.SNO = ENROL.SNO; ③ SELECT STUDENT.SNAME, ENROL.COURSE FROM ENROL LEFT OUTER JOIN STUDENT ON ENROL.SNO = STUDENT.SNO; ④ SELECT STUDENT.SNAME, ENROL.COURSE FROM STUDENT RIGHT OUTER JOIN ENROL ON STUDENT.SNO = ENROL.SNO; --..
