MySQL foreign key constraints, cascade delete

Posted by Cudos on Stack Overflow See other posts from Stack Overflow or by Cudos
Published on 2010-05-26T16:32:59Z Indexed on 2010/05/26 20:51 UTC
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mysql

|

foreign-keys

|

innodb

Hello.

I want to use foreign keys to keep the integrity and avoid orphans (I already use innoDB).

How do I make a SQL statment that DELETE ON CASCADE?

Secondly, that using DELETE ON CASCADE. E.g. if I delete a category then it would delete products related to that category even though there are other categories related to those products.

The pivot table "categories_products" creates a many-to-many relationship between the two other tables.

categories
- id (INT)
- name (VARCHAR 255)

products
- id
- name
- price

categories_products
- categories_id
- products_id

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