如果您们在尝试的过程中遇到什么问题或者我的代码有错误的地方，请给予指正，非常感谢！
联系方式：david.louis.tian@outlook.com
版权＠：转载请标明出处！MySQL数据表的基本操作二：表结构查看、修改与表操作(二)
, 0 rows affected (0.07 sec)
mysql> create table employee
-> (
-> id int(11) primary key,
-> name varchar(25),
-> department_id int(11),
-> salary float,
-> constraint fk_emp_dept foreign key(department_id) references department(id)
-> );
Query OK, 0 rows affected (0.10 sec)
mysql> drop table department;
ERROR 1217 (23000): Cannot delete or update a parent row: a foreign key constraint fails
mysql> alter table employee drop foreign key fk_emp_dept;
Query OK, 0 rows affected (0.22 sec)
Records: 0 Duplicates: 0 Warnings: 0
mysql>
drop table department;
Query OK, 0 rows affected (0.04 sec)
mysql> show tables;
+------------------+
| Tables_in_rm_tab |
+------------------+
| employee |
+------------------+
1 row in set (0.00 sec)