MySQL Syntax in creating Foreign Key
Is this syntax correct in creating a Foreign Key?
create table department
(
de开发者_开发技巧partmentID 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;
It looks like MySQL accepts it (doesn't complain about the syntax) but the foreign key is not actually created.
To create this foreign key, run this command:
ALTER TABLE employee ADD CONSTRAINT fk_department FOREIGN KEY (departmentID) REFERENCES department (departmentID);
create table employee
(
employeeID int not null auto_increment primary key,
name varchar(80),
job varchar(30),
departmentID int not null ADD CONSTRAINT fk_department FOREIGN KEY (departmentID) references department(departmentID)
)
FOREIGN KEY (departmentID) REFERENCES department(departmentID)
Thanks.!
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