查询选修了a001号课程且成绩在60分以上的所有学生
A: select * from course where cid=’a001’ and grade>=60
B: select * from student where cid=’a001’ and grade>=60
C: select * from sc where cid=’a001’
D: select * from sc where cid=’a001’ and grade>=60
A: select * from course where cid=’a001’ and grade>=60
B: select * from student where cid=’a001’ and grade>=60
C: select * from sc where cid=’a001’
D: select * from sc where cid=’a001’ and grade>=60
举一反三
- 查询选修了a001号课程的学生的最高成绩（） A: select cid, max(grade) from course where cid=’a001’ group by cid B: select cid,max(grade) from student where cid=’a001’ group by cid C: select cid, max(grade) from sc where cid=’a001’ group by cid D: select cid, max(grade) from student group by cid having cid=’a001’
- 统计选修了a001课程的学生的平均成绩( ) A: select cid,avg(grade) from student group by cid having cid=’a001’ B: select cid,avg(grade) from student where cid=’a001’ group by cid C: select cid,avg(grade) from course where cid=’a001’ group by cid D: select cid,avg(grade) from sc where cid=’a001’ group by cid
- 按照课程号进行分组，统计学生平均成绩大于60分的学生的信息( ) A: select cid,avg(grade) from sc group by cid having avg(grade)>60 B: select cid,avg(grade) from student group by cid having avg(grade)>60 C: select cid,avg(grade) from course where avg(grade)>60 group by cid D: select cid,avg(grade) from student where avg(grade)>60 group by cid
- 查询成绩在60分以上的学生的信息及其选课的课程号和成绩 A: select student.*,cid,grade from student,sc where student.sid=sc.sid and grade>=60 B: select * from student,sc where student.sid=sc.sid where grade>=60 C: select * from student,sc where student.sid=sc.sid where student.sid=sc.sid D: select * from student,course where grade>=60
- 查询学生的学号，姓名，选修课程号和课程成绩 A: select sid,sname,cid,grade from student,sc where student.sid=sc.sid B: select * from student,sc where student.sid=sc.sid C: select sid,sname,cid,cname from student,course D: select sid,sname,cid,cname from student,sc