SELECT ( Sum(r.marks_attained) / Sum(r.total_marks) * 100 )AS marks,
s.name
FROM result r,
student s
WHERE r.student_id = s.student_id
GROUP BY r.student_id
AND
ORDER BY marks DESC
我如何才能只获得百分比大于 90 的学生分数?
我可以在 where 子句中使用标记吗?