At 17:29 +0200 9/27/02, Remco Barendse wrote:
>According to the website MySQL 4.0.x supports "foreign key constraints".
>For version 4.1 "foreign key integrity rules" are planned.
>What is the difference between these 2? On previous versions of MySQL it
>was possible to create foreign keys but changed data was not replicated to
>I need foreign key support for MySQL as is available in PostgreSQL.
>Any input greatly appreciated!
InnoDB tables support foreign key definitions as of 3.23.44. This means
you cannot insert records into a child table unless the key value is listed
in the parent table.
MySQL 3.23.50 adds support for ON DELETE CASCADE and ON DELETE SET NULL.
This causes deletion of records in the parent table to affect the child
ON UPDATE is not supported.