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select a.studentid "ѧ ºÅ",studentname "ѧÉúÐÕÃû",
subjectname "¿Î³ÌÃû³Æ",
decode(sign(mark-60),-1,'²»¼°¸ñ','¼°¸ñ') "³É ¼¨"
from student a,subject b,grade c
where a.studentid = c.studentid
and b.subjectid = c.subjectid
2.
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