From: Date: February 26 2004 3:48pm
Subject: Re: Bug in new FOREIGN KEY checks in MySQLInnoDB/4.0.18
List-Archive: http://lists.mysql.com/bugs/15256
Message-Id: <16446.1832.777539.166765@sinisa.nasamreza.org>
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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,

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