第四章高階查詢

--案例1：檢查「oop」課程最近一次考試。--如果有80分以上的成績，則每人提2分；

--否則，每人提5分。最終的成績不得大於100分
if exists
(	  select studentresult from result
where subjectid=
(select subjectid from subject
where subjectname='oop'
)and examdate=
(select max(examdate) from result
where subjectid=
(		  select subjectid from subject
where subjectname='oop'
)	  )
and studentresult>80
)	begin
--有，每人提2分  99
update result set studentresult=100 
where subjectid=
(select subjectid from subject
where subjectname='oop'
)and examdate=
(select max(examdate) from result
where subjectid=
(		  select subjectid from subject
where subjectname='oop'
)	  )
and studentresult>98
update result set studentresult+=2 
where subjectid=
(select subjectid from subject
where subjectname='oop'
)and examdate=
(select max(examdate) from result
where subjectid=
(		  select subjectid from subject
where subjectname='oop'
)	  )
and studentresult<=98
endelse
begin
--沒有，整體+5
update result set studentresult+=5
where subjectid=
(select subjectid from subject
where subjectname='oop'
)and examdate=
(select max(examdate) from result
where subjectid=
(		  select subjectid from subject
where subjectname='oop'
)	  )
endselect * from result
where subjectid=
(select subjectid from subject
where subjectname='oop'
)and examdate=
(select max(examdate) from result
where subjectid=
(		  select subjectid from subject
where subjectname='oop'
)	  )

---分頁：雙top 雙order by  每頁顯示3條記錄,我想要第二頁資料 4-6條

select top 3 * from student
where studentno not in
(   select top 0 studentno from student
)

select *from student

子查詢select *from student
where birthday >(select birthday from student where studentno='23311')
--最高分   最低分
select max (studentresult),min(studentresult)from result 
where examdate=
(select max (examdate) from result where subjectid =
(select subjectid from subject where subjectname ='oop'))
and subjectid=
(select subjectid from subject where subjectname ='oop'
)--查詢參加'oop'課程最近一次的在讀學生名單(學生姓名,學生編號)
select studentname,studentno
from student
where studentno in
(select studentno from result 
where subjectid=
(select subjectid from subject
where subjectname='oop'
)and examdate=
(select max (examdate) from result 
where subjectid=
(select subjectid from subject
where subjectname='oop'))
)

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