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# Student(S#,Sname,Sage,Ssex) ѧÉú±í
# Course(C#,Cname,T#) ¿Î³Ì±í
# SC(S#,C#,score) ³É¼¨±í
# Teacher(T#,Tname) ½Ìʦ±í
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update
sc
set
sc.score = tt.avg_score
from t_sc sc,
(
select c_id , avg(score) avg_score from t_sc where c_id in(
select c.id from t_teacher t,t_course c where t.id = c.t_id and t.tname = 'ÕÅÀÏʦ'
)group by c_id
)tt
where tt.c_id = sc.c_id
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create table jskb(
񅧏 int identity(1,1) primary key not null,
ÐÕÃû varchar(20) not null,
ÐÔ±ð char(1) not null ,
ÊÚ¿ÎÃû varchar(10) not null,
½ÌÊҺŠint(10)
)
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