At 23:12 +0200 3/16/03, Heikki Tuuri wrote:
>Tor,
>
>----- Original Message -----
>From: ""Tor R. Skoglund (NextG)"" <trskog@stripped>
>Newsgroups: mailing.database.mysql
>Sent: Sunday, March 16, 2003 10:11 PM
>Subject: Foreign Key and default action/RESTRICT behaviour?
>
> > Hi List, regarding the foreign key definitions:
>>
>> [CONSTRAINT symbol] FOREIGN KEY (index_col_name, ...)
>> REFERENCES table_name (index_col_name, ...)
>> [ON DELETE {CASCADE | SET NULL | NO ACTION
>> | RESTRICT}]
>> [ON UPDATE {CASCADE | SET NULL | NO ACTION
>> | RESTRICT}]
>>
>> Is there a default action for ON DELETE and ON UPDATE if no action
>> is specified in the database definition?
>
>RESTRICT is, of course, the default 'action'. ON DELETE and ON UPDATE are
>later additions.
I see in the change notes that ON UPDATE was implemented in 4.0.8.
But how can ON DELETE be a later addition than RESTRICT? I was under the
impression that RESTRICT wasn't even implemented.
Also, the manual lists SET DEFAULT as a reference option for the general
CREATE TABLE syntax. Does that come into play for InnoDB at all?
>
>...
>
>> Best regards,
>> Tor Rune Skoglund
>> trskog@stripped
>
>Heikki Tuuri
>Innobase Oy
>---
>InnoDB - transactions, hot backup, and foreign key support for MySQL
>See http://www.innodb.com, download MySQL-4.0 from http://www.mysql.com
--
Paul DuBois
http://www.kitebird.com/
sql, query
