數據庫表中一對多關系怎么設計？

Database Design（數據庫設計）


馬克-to-win：

(一對多：one-to-many)

1) teacher and student.

(teacher表:兩列id（主鍵）,name。
pupil表: 三列：id（主鍵）,name,tid(外鍵))

 

舉例： Teacher "qixy" has two students: liyaohua,fuwenlong. Teacher "huanglaosh" has two students: mashuai,jiaxiaohu.

create table pupil(id int not null,name char(10),tid int);

create table teacher(id int not null,name char(10));

INSERT INTO pupil (id,name,tid) VALUES(1,'liyaohua',1);
INSERT INTO pupil (id,name,tid) VALUES(2,'fuwenlong',1);
INSERT INTO pupil (id,name,tid) VALUES(3,'mashuai',2);
INSERT INTO pupil (id,name,tid) VALUES(4,'jiaxiaohu',2);

INSERT INTO teacher (id,name) VALUES(1,'qixy');
INSERT INTO teacher (id,name) VALUES(2,'huanglaosh');

select * from pupil,teacher where tid=teacher.id and teacher.name='qixy';

+----+-----------+------+----+------+
| id | name      | tid  | id | name |
+----+-----------+------+----+------+
|  1 | liyaohua  |    1 |  1 | qixy |
|  2 | fuwenlong |    1 |  1 | qixy |
+----+-----------+------+----+------+
 

更多內容請見原文，文章轉載自：https://blog.csdn.net/qq_44591615/article/details/109205809