sql语句查询数据是和三张表有关联的应该怎么写?

2025-03-24 06:38:05

推荐回答（4个）

回答（1）：

select School.SchoolID,Student.StudentName
from School full join Class on School.ClassId=Class.ClassId full join Student on Class.StudentId=Student.StudentId

要查找的东西放在最上面，然后连接表，连接条件。就这样。

回答（2）：

select School.SchoolID,Student.StudentNamefrom Student left join Class on Student.StudentId = Class.Student left join School on Class.ClassId = School.ClassId

回答（3）：

select schoolID,StudentName from school join class on school.classid=class.classid join student on class.studentid=student.studentid
或者
select schoolID,StudentName from school,class,student where school.classid=class.classid and class.studentid=student.studentid

回答（4）：

SELECT SCHOOLID,STUDENTNAME FROM SCHOOL,CLASS,STUDENT
WHERE SCHOOL.CLASSID=CLASS.CLASSID AND CLASS.STUDENTID=STUDENT.STUDENTID