MariaDB "Foreign key constraint is incorrectly formed" 错误

MariaDB "Foreign key constraint is incorrectly formed" error

浏览其他类似问题没有帮助,我正在创建两个简单的 tables 并弹出此错误,不知道哪里出了问题:

create table department (
    dept_name varchar(20),  
    building varchar(15),  
    budget numeric(12,2),  
    primary key (dept_name)
) COLLATE='utf8_general_ci' ENGINE=INNODB;

现在当我创建第二个时 table:

create table course (
    course_id varchar(7), 
    title varchar(50), 
    dept_name varchar(20), 
    credits numeric(2,0), 
    primary key (course_id), 
    foreign key (dept_name) references department
) COLLATE='utf8_general_ci' ENGINE=INNODB;

它给了我错误。我在这里错过了什么?

外键语法为:

foreign key (dept_name) references department(dept_name)
                       --  column name here --^