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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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SQL code:
1¡¢²éѯ¡°001¡±¿Î³Ì±È¡°002¡±¿Î³Ì³É¼¨¸ßµÄËùÓÐѧÉúµÄѧºÅ£»
select a.S# from (select s#,score from SC where C#='001') a,(select s#,score
from SC where C#='002') b
where a.score>b.score and a.s#=b.s#;
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SQL code:
select a.s#
from sc a join sc b on a.s#=b.s#
where a.c#='001' and b.c#='002' and a.score>b.score
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£º ......
DateTime startTime=DateTime(em_1.Text)
DateTime endTime=DateTime(em_2.Text)
string sql
sql = dw_1.GetSQLSelect()+"Where (StartTime> '"+startTime+"') and (EndTime ......
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tb1
col col1
abc 111
cde 111
qaz 222
tgb 222
tb2
col2 col3
abc 111&n ......
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id parentid name
1 0
2 0
3 1
4 3
5 2
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4 5
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