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Home Backend Development PHP Tutorial SQL语句问题,关联查询,一对多

SQL语句问题,关联查询,一对多

Jun 23, 2016 pm 01:46 PM

比如老师和学生表,一个老师对应多个学生。想查出来老师A和他对应的学生1,2,3,老师B和他对应的4,5,6.


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select * from 学生表 a,教师表 b,教师学生关系表 c where a.studentid = c.studentid and b.teacherid = teacherid and b.teacherid = 你要查的老师id
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表结构是怎样的?
table teacher
id name
1     A
2     B

table student
id  tid
1    1
2    1
3    1
4    2
5    2
6    2

A老师的学生
select * from student where tid=1;

B老师的学生
select * from student where tid=2;

或者 select a.*,b.name from student as a left join teacher as b on a.tid = b.id order by a.tid;

老师有个ID  查询 符合这个ID 条件的所有学生...

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