建表语句点击详见
– 查询不同课程成绩相同的学生的学生编号、课程编号、学生成绩
SELECT
st
.s_id
,
st
.s_name
,
sc
.c_id
,
sc
.s_score
FROM student st
LEFT JOIN score sc
ON sc
.s_id
=st
.s_id
LEFT JOIN course c
ON c
.c_id
=sc
.c_id
WHERE (
SELECT
COUNT(1)
FROM student st2
LEFT JOIN score sc2
ON sc2
.s_id
=st2
.s_id
LEFT JOIN course c2
ON c2
.c_id
=sc2
.c_id
WHERE sc
.s_score
=sc2
.s_score
AND c
.c_id
!=c2
.c_id
)>1
