MYSQL外键未更新表

Question

Table 1:

+--------------+-------------+------+-----+---------+----------------+
| Field        | Type        | Null | Key | Default | Extra          |
+--------------+-------------+------+-----+---------+----------------+
| ID           | int(11)     | NO   | PRI | NULL    | auto_increment |
| FONO         | int(11)     | NO   | MUL |         |                |
| Description  | varchar(25) | NO   |     |         |                |
| Amount       | varchar(60) | NO   |     |         |                |
+--------------+-------------+------+-----+---------+----------------+

Table 2:

+--------------+-------------+------+-----+---------+----------------+
| Field        | Type        | Null | Key | Default | Extra          |
+--------------+-------------+------+-----+---------+----------------+
| FONO         | int(11)     | NO   | PRI | NULL    | auto_increment |
| FINVNO       | varchar(20) | NO   |     |         |                |
| Description  | varchar(25) | NO   |     |         |                |
| Amount       | varchar(60) | NO   |     |         |                |
+--------------+-------------+------+-----+---------+----------------+

I would like the Column FONO in table 1 automatically get the value from the FONO column in table 2. I have set it up so that on update it cascades.

Although when the records are being entered the FONO column in table 1 remains empty.

Why is this happening? What can I do to solve this?

Thank You.

Answer 1

Cascade happen on deleting and update the primary key that in which its foreign key is defined with cascade behavior and not insertion.

ON DELETE CASCADE

ON UPDATE CASCADE

Just check out more here