本文介绍了MySQL 创建外键的语法的处理方法,对大家解决问题具有一定的参考价值,需要的朋友们下面随着小编来一起学习吧!
问题描述
这种语法在创建外键时是否正确?
Is this syntax correct in creating a Foreign Key?
create table department
(
departmentID int not null auto_increment primary key,
name varchar(30)
) type=InnoDB;
create table employee
(
employeeID int not null auto_increment primary key,
name varchar(80),
job varchar(30),
departmentID int not null references department(departmentID)
) type=InnoDB;
推荐答案
看起来 MySQL 接受它(不抱怨语法),但实际上并没有创建外键.
It looks like MySQL accepts it (doesn't complain about the syntax) but the foreign key is not actually created.
要创建这个外键,运行这个命令:
To create this foreign key, run this command:
ALTER TABLE employee ADD CONSTRAINT fk_department FOREIGN KEY (departmentID) REFERENCES department (departmentID);
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