摘要:
题目38:检索至少选修两门课程的学生学号 SELECT studentid ,COUNT(courseid) AS a FROM student_score GROUP BY studentid HAVING a >=2 题目39:查询选修了全部课程的学生信息 GROUP BY studentid 阅读全文
摘要:
题目32:求每门课程的学生人数 分析: 这个直接是group by 然后 count SELECT courseid, COUNT(studentid) FROM student_score GROUP BY courseid 题目33:查询选修「张三」老师所授课程的学生中,成绩最高的学生信息及其成 阅读全文