Re: Bug in new FOREIGN KEY checks in MySQLInnoDB/4.0.18

[Sinisa Milivojevic]

Steve Hay writes:
> Hi,
> 
> I've just upgraded from MySQL 4.0.16 to 4.0.18 and now find that some 
> commands that used to work without error (dropping and re-creating a 
> database) no longer work.
> 
> The error is:
> 
>     error: 'Cannot delete or update a parent row: a foreign key 
> constraint fails'
> 
> which presumably relates to the first item in the InnoDB version history 
> (http://www.innodb.com/ibman.php#InnoDB.history).  (All the tables in 
> the database concerned are InnoDB tables.)
> 
> It appears that the foreign key constraint is being checked even when 
> dropping the database, which I assume is not intended.
> 
> I tried a simple case of one table X referencing another table Y, and 
> "DROP DATABASE" works fine (even with data in it, so foreign key 
> constraints are not being checked here, which is as I would expect).  I 
> tried another case with two tables X and Y referencing one table Z, but 
> still no error.  Finally, I reproduced my problem by having table X 
> referencing table Y and table Y referencing table Z.
> 
> The following DOS command-lines result in the error above:
> 
> I'm running Windows XP SP1.
> 
> Regards,
> - Steve
> 

Hi!

Yes, the above is now the expected behaviour and it is documented in
our Changelog.

All you have to do is drop tables in the right order.

-- 

Sincerely,

-- 
For technical support contracts, go to https://order.mysql.com/?ref=msmi
   __  ___     ___ ____  __
  /  |/  /_ __/ __/ __ \/ /    Mr. Sinisa Milivojevic <sinisa@stripped>
 / /|_/ / // /\ \/ /_/ / /__   MySQL AB
/_/  /_/\_, /___/\___\_\___/   Full time Developer and Support Coordinator
       <___/   www.mysql.com   Larnaca, Cyprus

Meet the MySQL at User Conference ! (April 14-16, 2004)
http://www.mysql.com/uc2004/