本篇博客用来记录自己在做SQL server练习的时候,所做过的题目,遇到的问题及总结。
题目及解答:
本练习所涉及的数据库:stuManage
1、写出下面SQL语句实现的功能
(1)SELECT COUNT(*) AS 信管专业女学生人数
FROM student
WHERE mno=‘100165’ AND ssex=‘女’
统计了出信管专业(100165)女学生总人数。
(2)SELECT DISTINCT SUBSTRING(sname,1,1)
FROM student
查询出全部学生的姓。
(3)SELECT sno,sname,ssex,mno
FROM student
WHERE mno IN (‘100165’,’201148’,’100838’)
查询出mno是‘100165’或’201148’或’100838’的学生达到学号,姓名,性别和专业号。
(4)CREATE VIEW v_1
AS
SELECT ccno,mark
FROM student_course
WHERE sno =‘100212201’ AND mark >ANY
(SELECT mark FROM student_course
WHERE sno =‘100212208’ )
创建一个视图v_1,该视图要求,学号为100212201的同学,
大于学号为100212208的同学所有科目的平均分的科目,
列出课程号和成绩。视图包含课程号和成绩两个字段。
(5)SELECT DISTINCT s.sno,sname,dname
FROM student AS s,department AS d, student_course as sc ,major as m
WHERE s.mno=m.mno and d.dno=m.dno AND s.sno=sc.sno AND mark <60
找出课程成绩小于60分的同学,列出他们的学号,姓名和院系名(dname)。
(6)SELECT sno,sname,mname
FROM student AS s,major AS m
WHERE s.mno=m.mno AND s.sno IN
(SELECT DISTINCT sno
FROM student_course
WHERE mark <60 )
找出课程成绩小于60分的同学,列出他们的学号,姓名和专业名。
2、根据下面的要求,写出相应的查询语句
(1)查询所有男同学的选课情况,要求列出学号、姓名、开课号、分数。
select student.sNo,student.sName,ccNo,Mark
from student_course,student
where student_course.sNO =student.sNO
and student.sSex='男';
(2)创建一个视图显示所有学生的总成绩,最高成绩,要求列出学号、总成绩和最高成绩。
create view student_mark_view
as select sNo,sum(mark) as 总成绩,max(mark) as 最高成绩 from student_course group by sNo;
(3)查询出姓张的学生或者姓名中带有“秋”的学生
select * from student
where sName like '张%' or sName like '%秋%';
(4)查询出每门课程的平均分、最低分、最高分
select ccNo,avg(mark) as 平均分 ,min(mark) as 最低分, max(mark) as 最高分 from student_course group by ccNo;
(5)查询出平均分大于80分,且至少选修了2门课程的学生学号。
select sNo from student_course group by sNo having AVG(mark)> 80
and count(ccNo)>=2;
(6)求选修课程号为’010104’且成绩在90以上的学生学号、姓名和成绩
select student.sNo,sName,student_course.mark from student,student_course
where student.sNO = student_course.sNO
and ccNo='010104' and mark>90;
(7)创建一个视图显示每一门课程的间接先行课(即先行课的先行课)
select a.cno,a.cname,b.cpno as '间接先行课'
from course a,course b
where a.cpno = b.cno;
(8)求高等数学课程的成绩高于刘晨的学生学号和成绩
select student.sNO,student.sName,student_course.Mark
from student,student_course,course,course_class
where student.sno=student_course.sno
and student_course.ccNO = course_class.ccNo
and course_class.cNo = course.cno
and course.cName='高等数学'
and student_course.Mark>
(select student_course.mark from student,student_course
where student.sNO=student_course.sNO
and student.sName='刘晨'
and student_course.ccNO = course_class.ccNO);
(9)求其他系中比计算机系某一学生年龄小的学生(即年龄小于计算机系年龄最大者的学生)
select * from student,department,major
where student.mNO=major.mno
and major.dNO = department.dNO
and department.dName!='计算机系'
and DateDiff(yy,student.sBirth,getDate())<
(select Max(DateDiff(yy,student.sBirth,getDate())) from student
where student.mNo = major.mNO
and major.dNO = department.dNO
and department.dName!='计算机系'
);
(10)查询同时选修了“数据库”“金融学”“统计学”三门课程的学生姓名。(要求使用EXISTS)
create view three_course_view
as select student.sName,course.cName from student,student_course,course_class,course
where student.sNO = student_course.sNO
and student_course.ccNO = course_class.ccNo
and course_class.cNo = course.cNo;
SELECT sName FRO