Student：

Score

1.查询年龄超过20岁的姓名\年龄\所在班级
 select
   sName,
   sAge,
   cName
   from Student as TS
   inner join Class TC
   on TC.clsId=TS.sClassId
   where sAge>20

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2.查询出所有参加考试的同学的学生编号，姓名，考试成绩。
select 
sId,
sName,
english,
math
from Student
inner join Score on Score.studentId=Student.sId

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3.查询出所有没有参加考试的同学的学生编号，姓名，考试成绩。
select 
sId,
sName
from Student
 where sId not in(select studentId from Score)

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4使用联接重做：查询出所有没有参加考试的同学的学生编号，姓名。
--(1)
select sId,sName
from (
select sId,sName,sAge,score.*
from Student left outer join Score 
on Score.studentId=Student.sId) as TB1
where scoreId is null

--(2)
select sId,sName
from (
select sId,sName,sAge,score.*
from Score  right outer join Student
on Score.studentId=Student.sId) as TB1
where scoreId is null

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5、查询所有英语及格的学生姓名、年龄及成绩
select 
sName,
sAge,
english
from Student
inner join Score
on Score.studentId=Student.sId
where english>=60