id做課程表
① 三個表 student Sid(學生ID) Sname(姓名) Sage(年齡) Ssex(性別)
select student.Sid,student.Sname
from student,課程自表,成績表
where student.Sid=成績表.SCSid and 成績表.Cid=課程表.CourseCid and 課程表.CourseCid="001" or 課程表.CourseCid="002"
group by student.Sid,student.Sname
having count(*)=2;
② 3張表,課程表(課程id,課程名,分類) 學生表(學生id,學生姓名) 成績表(學生id,課程id
select a.課程名,b.學生姓名,max(c.分數) from 課程表 a ,學生表 b ,成績表 c where a.課程id=c.課程id and b.學生id=c.學生id
③ 三張表,學生表有id.name課程表有課程id課程name選課表有學生id課程id求顯示選了兩門哥的學生信息
(C,10)年齡(N,2),性別(C,2) 課程表:課程編號(C,回3),答課程名稱(C,10),課時(N,4),任課教師(C,10) 選課表:學號(C,6),課程編號(C,3),成績(N,2) 是寫出完成以下操作的SQL命令:1.查詢所有學生的信息 2.查詢所有課程的課程名稱和任課教師 3.查詢出姓「李」的學生的基本信息 4.查詢選課表中分數介於80分至90分之間的記錄 5。求學生總數 6.查詢年齡比唐潔小的所有學生的基本信息 8.在學生表中插入一條記錄:學號:9000101,姓名;李麗,年齡:20 9。查詢出200807號學生的姓名及其所選課程的名稱 10.在學生表中增加一個「電話號碼」欄位(文本型(8字元))
④ 如何設置外鍵,有三個表,學生表(ID,學號,課程號,成績),課程表(ID,課程號,課程名)
學生表中的學號是否唯一且必須?如果是的話,建議將ID及學號合並
課程表中的課程號是否唯一且必須?如果是的話,建議將ID及課程號合並
學生表中課程號是課程表中ID的外鍵,成績表中的課程號是課程表中ID的外鍵,成績表中的學號是學生表中ID的外鍵
⑤ 我寫了一個學生表(學生id,學生名字),寫了一個課程表(課程id,課程名字,學生id)
外鍵關聯的是另一張表的主鍵,將本表的這個欄位的值約束在關聯的主鍵范圍內。
你這個需求可以寫觸發器實現的
⑥ 學生表、課程表,學生課程關系表中怎麼修改學生id信息
問題1:原學生表中沒有學號是1的??,如果沒有可以改
update student set Stuid=1 where Stuid=(select stuid from card where score=100 and cid=(select cid from course where cmane='物理')) and sname='張三'
這個表改後card 表裡相專應的張三的數據就與student表裡不相符屬了.
delete from student where Stuid in (select stuid from card where score<60 and cid=(select cid from course where cname='英語'))
同樣的刪除數據後,找不到對應的student表裡的
這種結構的表之間應該還有外鍵關聯
像你這么改要亂套的
⑦ 資料庫查詢,有三張表學生表STU,課程表Course,SC學生課程關系表(s_id,c_id)
SELECTSTU.s_nameFROMSTU,(SELECTSC.s_idFROMSCGROUPBYs_id
HAVINGCOUNT(*)=(SELECTCOUNT(*)FROMCourse)AStmpWHERESTU.s_id=tmp.s_id
⑧ 設在學生資料庫中有三張表,表結構如下所示: Student(學生表): Student表的主鍵:sno(學號) Course(課程
(1) create table S_C
(sno char(10) not null
,cno char(8) not null
,score int null
,constraint PK_SC primary key (sno,cno)
)
(2)insert into Student (sno,sname,ssex)
values('1010','李小麗','女')
(3)create index IND_CName on Course (cname)
(4)update student set sage=23 where sno='1005'
(5)delete from course where cname='管理信息系統'
(6)select cno,cname,ctime
from course
where teacher='李元'
order by cno ASC
(7)select sno,sum(score) as score
from S_C
group by sno
(8)create view V_Student
as
select *
from student
where ssex='男' and sage>=18 and sage<=24
(9)select sno,sname
from student
where sno in (select sno from S_C where cno='001')
(10)select A.sno,A.sname
from student A
left join S_C B on A.sno=B.sno
left join Course C on B.cno=C.cno
where C.cname='關系資料庫'
(11)select sno,sname from
(select A.sno,A.sname,count(1) as count_
from student A
left join S_C B on A.sno=B.sno
group by A.sno,A.sname) A
where count_>3
(12)select C.sname
from
(select * from S_C where cno='002') A
inner join
(select * from S_C where cno='004' on) B on A.sno=B.sno
left join student C on A.sno=C.sno
⑨ SQL語句的一道題 三個基本表:學生表(Student)、課程表(Course)、學生選課表(SC)
1. select * from SC
2. select Sname,Sage from Student where Sdept = '計算機'
3. select Sno,Cno,Grade from SC where Grade >= 70 and Grade <= 80
4. select Sname,Sage from Student where Sage between 18 and 20 and Ssex = '男'
5. select top 1 Grade from SC where Cno = 'C01'
6. select max(Sage),min(Sage) from Student
7. select Sdept,sum(Sno) from Student group by Sdept
8. select course.Cname,sum(sc.Sno),max(Grade) from SC
join studet on Student.Sno = SC.Sno
join Course on Course.Cno = SC.Cno
group by course.cname,max(grade)
9. select sum(Cno),avg(Grade) from SC
join Course on Course.Cno = SC.Cno
join Student on Student.Sno= SC.Sno
order by SC.Sno
10. select Stuent.Sno,Stuent.Sname,sum(Grade) A from SC
join Student on Student.Sno = SC.Sno
group by sc.Sno,student.Sname
having A > 200
11. select Student.Sname,Student.Sdept from Student
join Course on Course.Cno = SC.Cno
join SC on SC.Sno = Student.Sno
where SC.Cno = 'C02'
12. select Student.sname,course.cno,sc.grade from sc
join student on student.sno = sc.sno
join course on course.cno = sc.cno
where sc.grade >= 80
order by sc.grade desc
13. select cno,cname from
(
select course.cno,course.cname,sun(sno) from student
join course on course.cno = sc.cno
join sc on sc.sno = student.sno
group by cno,cname
having sun(sno) > 0
)
14. ① select student.sname,student.sdept from
(
select student.sname,student.sdept,course.cname from student
join sc on sc.sno = student.sno
join course on course.cno = sc.cno
where course.cname = 'C01'
)
② select student.sno,student.sname from
(
select student.sno,student.sname,student.sdept,sc.grade from sc
join student on student.sno = sc,sno
where student.sdept = '信息' and sc.grade >= 80
)
③ select top 1 student.sname from
(
select student.sname,student.sdept,sum(sc.grade) from sc
join student on student.sno = sc.sno
where student.sdept = '計算機'
group by student.sname,student.sdept
order by
)
15. delete from sc where grade < 50
16. update sc set grade += 5 from sc
join course on course.cno = sc.cn
join student on student.sno = sc.sno
where student.sno =
(
select student.sno from sc
join course on course.cno = sc.cno
where course.cname = 'c01'
)
17. update sc set grade += 10 from sc
join student on student.sno = sc.sno
where student.sno =
(
select student.sno from student
join sc on sc.sno = student.sno
join course on course.cno = sc.cno
where student.sdept = '計算機' and course.cname = '計算機文化基礎'
)
18. create view [A] as
select student.sno,student.sname,student.sdept,course.cno,course.cname,sc.grade from sc
join student on student.sno = sc.sno
join course on course.cno = sc.cno
19. create view [A] as
select student.sno,avg(sc.grade) from sc
join student on student.sno = sc.sno
group by student.sno
20. create view [A] as
select student.sno,sum(sc.grade) from sc
join student on student.sno = sc.sno
group by student.sno
21. create index A on student(sname)
22. 不會
⑩ 現有2個表: 學生表:Student表(StudentId,StudentName) 課程表(課程ID,課程名稱)
select UserID,student.Name UserName,課程表名.Name Cousename
from student,課程表名