问：mysql外键不能约束
下面是我输入的内容mysql> create table t_book( fid varchar(20) primary key, fname varchar(100), fpageconut int, fauthorid varchar(20), foreign key(fauthorid) references t_author(fid));
Query OK, 0 rows affected (0.01 sec)
mysql> describe t_author;
+--------+--------------+------+-----+---------+-------+
| Field| Type | Null | Key | Default | Extra |
+--------+--------------+------+-----+---------+-------+
| fid | varchar(20)| NO | PRI | | |
| fname| varchar(100) | YES| | NULL | |
| fage | int(11) | YES| | NULL | |
| femail | varchar(20)| YES| | NULL | |
+--------+--------------+------+-----+---------+-------+
4 rows in set (0.00 sec)
mysql> insert into t_book values('3','hello start',354,'8');
Query OK, 1 row affected (0.00 sec)
mysql> select * from t_author;
+-----+----------+------+--------------------+
| fid | fname | fage | femail |
+-----+----------+------+--------------------+
| 1 | lily | 20 | lily@gmail.com |
| 2 | kingchou | 23 | kingchou@gmail.com |
| 3 | stef | 28 | stef@gmail.com |
| 4 | long | 26 | long@gmail.com |
| 5 | badboy | 31 | badboy@gmail.com |
+-----+----------+------+--------------------+
5 rows in set (0.00 sec)
mysql>
上面的那条insert 语句竟然能输入 不知道原因
可否给个解释？
check约束也不能约束 据说官方解释是增强移植问题 确定表是INNODB？
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