select * from Student select * from Class select * from Score select * from Subject --1、查询出和张三住在同一个地方的学生信息 select * from Student where StuAddress= (select StuAddress from Student where StuName=‘张三‘) --2、查询年龄大于李四的学生信息 select * from Student where StuAge> (select StuAge from Student where StuName=‘李四‘) --3、查询和张三在同一个班级的学生信息 select * from Student where ClassID= (select ClassID from Student where StuName=‘张三‘) --4、查询出所有脱产班的学生信息 select * from Student where ClassID in (select ClassID from Class where ClassType=‘脱产‘) --5、查询出没有参加过任何考试的学生信息 select * from Student where StuID not in (select StuID from score) --6、把和张三在同一个班级的所有学生的JAVA成绩加10分 update Score set Marks+=10 where StuID in (select StuID from Student where ClassID= (select ClassID from Student where StuName=‘张三‘) ) and SubId=(select SubId from Subject where SubName=‘JAVA‘) --7、查询比张三的JAVA成绩好的学生信息 select * from Student where StuID in (select StuID from Score where Marks> (select Marks from Score where StuID=(select StuID from Student where StuName=‘张三‘) and SubId=(select SubId from Subject where SubName=‘JAVA‘) ) ) --8、查询比张三的JAVA成绩好的学生所在的班级的信息 select * from Class where ClassID in (select ClassID from Student where StuID in (select StuID from Score where Marks> (select Marks from Score where StuID=(select StuID from Student where StuName=‘张三‘) and SubId=(select SubId from Subject where SubName=‘JAVA‘) ) ) ) --9、查询比S1T21班所有学生年龄大的“周末班”的学员信息 select * from Student where StuID in (select StuID from Student where StuAge> (select max(StuAge) from Student where ClassID in (select ClassID from Class where ClassType=‘周末‘ ) ) ) --10、查询统计出每个脱产班的班级编号、班级类型、开班日期、JAVA平均分、C#平均分、SQL平均分、HTML平均分 select c.ClassID 班级编号,c.ClassType 班级类型,c.ClassDate 班级日期 , avg(case SubName when ‘JAVA‘ then Marks end) JAVA平均分, avg(case SubName when ‘C#‘ then Marks end) C#平均分, avg(case SubName when ‘SQL‘ then Marks end) SQL平均分, avg(case SubName when ‘HTML‘ then Marks end) HTML平均分, avg(Marks) 平均分 from Student st inner join Class c on st.ClassID=c.ClassID inner join Score sc on sc.StuID=st.StuID inner join Subject su on su.SubId=sc.SubId where c.ClassType=‘脱产‘ group by c.ClassID,c.ClassType,c.ClassDate --11、查询出JAVA成绩比S1T21班JAVA成绩最高分要高的学员信息 select * from Student where StuID in( select StuID from Score where Marks>( select max(Marks) from Score where SubId=(select SubId from Subject where SubName=‘JAVA‘) and StuID in(select StuID from Student where ClassID=‘S1T21‘) ) and SubId=(select SubId from Subject where SubName=‘JAVA‘) ) --12、查询出JAVA成绩没有及格的学员信息 select * from Student where StuID in( select StuID from Score where Marks<60 and SubId=(select SubId from Subject where SubName=‘JAVA‘) ) --13、查询出姓“王”的学生的JAVA成绩和C#成绩 select * from Score where StuID in ( select StuID from Student where StuName like ‘王%‘ ) select st.StuName 姓名, (case SubName when ‘JAVA‘ then Marks end) JAVA成绩, (case SubName when ‘C#‘ then Marks end) C#成绩 from Score sc inner join Student st on sc.StuID=st.StuID inner join Subject su on sc.SubId=su.SubId where st.StuID in ( select StuID from Student where StuName like ‘王%‘ ) group by st.StuName,(case SubName when ‘JAVA‘ then Marks end),(case SubName when ‘C#‘ then Marks end) --14、SQLSERVER分页查询： --A、查询出学生信息表中第1-3条信息（第一页）； select top 3 * from Student where StuID not in( select top ((1-1)*3) StuID from Student ) --B、查询出学生信息表中第4-6条信息（第二页）； select top 3 * from Student where StuID not in( select top ((2-1)*3) StuID from Student ) --15、查询没有参加过JAVA考试的学生所在的班级编号、班级类型、开班日期 select st.StuName ,c.ClassID,c.ClassType,c.ClassDate from Student st inner join Class c on c.ClassID= st.ClassID where StuID not in ( select StuID from Score where SubId=(select SubId from Subject where SubName=‘JAVA‘) ) --16、查询出和“张三”在同一个班的班级人数，平均年龄 select ClassID,count(*) 班级人数,avg(StuAge) 平均年龄 from Student where ClassID=( select ClassID from student where StuName=‘张三‘ ) group by ClassID --17、查询出学生姓名、班级编号、考试科目名称、考试成绩（使用连接查询） select st.StuName,st.ClassID,su.SubName,sc.Marks from Score sc inner join Student st on sc.StuID=st.StuID inner join Subject su on sc.SubId=su.SubId --18、查询出班级人数最多的班级编号、班级类型、开班日期 select * from Class where ClassID in ( select ClassID from Student group by ClassID having count(*)=(select top 1 count(*) num from Student group by ClassID order by num desc) ) --19、由于张三、李四、王五三名同学JAVA考试作弊，现将三名同学的成绩作废（删除） delete from Score where StuID in (select StuID from Student where StuName in (‘张三‘,‘李四‘,‘王五‘)) and SubId=(select SubId from Subject where SubName=‘JAVA‘) --20、由于S1T23班参加的C#考试难度大，现将该班每个学生的C#成绩加10分 update Score set Marks+=10 where StuID in (select StuID from Student where ClassID=‘S1T23‘) and SubId=(select SubId from Subject where SubName=‘C#‘) --21、查询出年龄大于25并且家住湖北襄樊的学生的编号、姓名、班级编号、班级类型、开班日期 select st.StuID,st.StuName,st.ClassID,c.ClassType,c.ClassDate from Student st inner join Class c on st.ClassID=c.ClassID where StuID in ( select StuID from Student where StuAge>25 and StuAddress=‘湖北襄樊‘ ) --22、查询统计出2010-1-1以前开班的学生人数和平均年龄 select count(*) 人数,avg(StuAge) 平均年龄 from Student where ClassID in ( select ClassID from Class where ClassDate<‘2010-1-1‘ ) --23、查询出每个班级JAVA成绩不及格的人数 select ClassID,count(StuID) JAVA成绩不及格的人数 from Student where StuID in ( select StuID from Score where Marks<60 and SubId=(select SubId from Subject where SubName=‘JAVA‘) ) group by ClassID select c.ClassID, count(case when SubName=‘JAVA‘ and Marks<60 then Marks end) JAVA成绩不及格的人数 from Student st inner join Class c on st.ClassID=c.ClassID inner join Score sc on sc.StuID=st.StuID inner join Subject su on su.SubId=sc.SubId group by c.ClassID --24、查询出每个班级没有参加JAVA考试的学生人数 select ClassID,count(*) 没有参加JAVA考试的学生人数 from Student where StuID not in ( select StuID from Score where SubId=(select SubId from Subject where SubName=‘JAVA‘) ) group by ClassID --25、根据学生的JAVA课程的分数，来评定级别: --成绩<60 :★ --60<=成绩<70:★★ --70<=成绩<80:★★★ --80<=成绩<90:★★★★ --90<=成绩<=100:★★★★★ --并且显示评定的等级信息 select st.StuName 学生姓名,sc.Marks 学生JAVA成绩, (case when Marks<60 then ‘★‘ when Marks>=60 and Marks<70 then ‘★★‘ when Marks>=80 and Marks<90 then ‘★★★★‘ when Marks>=90 and Marks<=100 then ‘★★★★★‘ else ‘ב end) JAVA课程的分数评级 from Score sc inner join Student st on sc.StuID=st.StuID where SubId=(select SubId from Subject where SubName=‘JAVA‘)
原文：https://www.cnblogs.com/whatarey/p/9313221.html