不多说,简单一些,提供一点思路select * from testresult tr
join studentinfo stu
on tr.sid = stu.sid
join itemcode ic
on tr.kid = ic.kid
group by stu.sid,ic.kid
join studentinfo stu
on tr.sid = stu.sid
join itemcode ic
on tr.kid = ic.kid
group by stu.sid,ic.kid
解决方案 »
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