Question

我在下面创建了两个表users和login_flag：

CREATE TABLE IF NOT EXISTS users (
    user_id int NOT NULL AUTO_INCREMENT,
    email varchar(200) NOT NULL,
    first_name varchar(100) NOT NULL,
    last_name varchar(100) NOT NULL,
    password varchar(200) NOT NULL,
    priv varchar(20) NOT NULL,
    status varchar(20) NOT NULL DEFAULT 'unlocked',
    ctime TIMESTAMP NOT NULL default CURRENT_TIMESTAMP,
    PRIMARY KEY (user_id)
);

CREATE TABLE IF NOT EXISTS login_flag (
    flag_id int NOT NULL AUTO_INCREMENT,
    user_id int NOT NULL,
    flag int NOT NULL DEFAULT 0,
    PRIMARY KEY (flag_id),
    FOREIGN KEY (user_id) REFERENCES users(user_id) ON DELETE CASCADE
);

mysql> select * from users;

| user_id | email          | first_name | last_name | password                                                     | priv  | status   | ctime               |

|       1 | admin@test.com | admin      | admin     | $2b$12$oMMYOM45LxzsibodyPPBx.JUocceiBoU0Ui2TrZaKEmXnhO0jkCTW | admin | unlocked | 2018-08-23 11:02:40 |

mysql> select * from login_flag;
+---------+---------+------+
| flag_id | user_id | flag |
+---------+---------+------+
|       1 |       1 |    0 |
+---------+---------+------+
1 row in set (0.00 sec)

我从users表中删除了记录：

mysql> delete from users where user_id='1';
Query OK, 1 row affected (0.16 sec)

这也应该从表login_flag中删除条目，但不是那样的。

mysql> select * from login_flag;
+---------+---------+------+
| flag_id | user_id | flag |
+---------+---------+------+
|       1 |       1 |    0 |
+---------+---------+------+
1 row in set (0.00 sec)

任何人都可以将我指向正确的方向，或者让我知道我做错了什么地方。

我还检查了foreign_key_checks，其值为ON

mysql> SHOW VARIABLES LIKE 'foreign_key_checks';
+--------------------+-------+
| Variable_name      | Value |
+--------------------+-------+
| foreign_key_checks | ON    |
+--------------------+-------+
1 row in set (0.00 sec)

我可以看到Engine是InnoDB

mysql> SHOW TABLE STATUS where Name = 'users'
    -> ;
+-------+--------+---------+------------+------+----------------+-------------+-----------------+--------------+-----------+----------------+---------------------+-------------+------------+-------------------+----------+----------------+---------+
| Name  | Engine | Version | Row_format | Rows | Avg_row_length | Data_length | Max_data_length | Index_length | Data_free | Auto_increment | Create_time         | Update_time | Check_time | Collation         | Checksum | Create_options | Comment |
+-------+--------+---------+------------+------+----------------+-------------+-----------------+--------------+-----------+----------------+---------------------+-------------+------------+-------------------+----------+----------------+---------+
| users | InnoDB |      10 | Compact    |    0 |              0 |       16384 |               0 |            0 |  10485760 |              2 | 2018-08-23 11:58:47 | NULL        | NULL       | latin1_swedish_ci |     NULL |                |         |
+-------+--------+---------+------------+------+----------------+-------------+-----------------+--------------+-----------+----------------+---------------------+-------------+------------+-------------------+----------+----------------+---------+
1 row in set (0.02 sec)

show create table login_flag;

mysql> show create table login_flag;
+------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| Table      | Create Table                                                                                                                                                                                                                                                                                                                                           |
+------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| login_flag | CREATE TABLE `login_flag` (
  `flag_id` int(11) NOT NULL AUTO_INCREMENT,
  `user_id` int(11) NOT NULL,
  `flag` int(11) NOT NULL DEFAULT '0',
  PRIMARY KEY (`flag_id`),
  KEY `user_id` (`user_id`),
  CONSTRAINT `login_flag_ibfk_1` FOREIGN KEY (`user_id`) REFERENCES `users` (`user_id`) ON DELETE CASCADE
) ENGINE=InnoDB DEFAULT CHARSET=latin1 |
+------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
1 row in set (0.00 sec)

在删除级联SQL不起作用

0 个答案: