Interesting. Thanks for that tip on showing the INNODB STATUS. It turned up the error:
A foreign key constraint of name `cc/fk_lessons` already exists. ...which tells me that a foreign key name cannot already be in use even if on a different table (at least that's what it appears to be saying). I named the foreign key something totally different than anything else in the database, and it worked. So, I guess foreign keys must have unique names like tables do. Thanks, Jesse -----Original Message----- From: Gavin Towey [mailto:gto...@ffn.com] Sent: Friday, May 14, 2010 1:45 PM To: j...@msdlg.com; mysql@lists.mysql.com Subject: RE: Can't create foreign key Perror 121 says: OS error code 121: Remote I/O error Which I'm not too sure why an ALTER to add an constraint would give that error. Normally though, foreign key errors are shown in the SHOW ENGINE INNODB STATUS \G output, look for more details there. Regards, Gavin Towey -----Original Message----- From: j...@msdlg.com [mailto:j...@msdlg.com] Sent: Friday, May 14, 2010 10:18 AM To: mysql@lists.mysql.com Subject: Can't create foreign key I'm trying to create a foreign key by executing the following statement: ALTER TABLE `cc`.`takenlessons` ADD CONSTRAINT `fk_lessons` FOREIGN KEY (`LessonID` ) REFERENCES `cc`.`lessons` (`id` ) ON DELETE CASCADE ON UPDATE NO ACTION , ADD INDEX `fk_lessons` (`LessonID` ASC) ; I'm using the RC of MySQL workbench to do this. When I execute this statement, I get the following error: Error Code: 1005 Can't create table 'cc.#sql-115c_61' (errno: 121)) In the past when I got a similar error, it was because the fields didn't match exactly. For instance, one may be Int(10) and one Int(11), or one may be Unsigned, and the other not. But, in this case, both match exactly. What other reasons are there for a foreign key creation to fail like that? Thanks, Jesse This message contains confidential information and is intended only for the individual named. If you are not the named addressee, you are notified that reviewing, disseminating, disclosing, copying or distributing this e-mail is strictly prohibited. Please notify the sender immediately by e-mail if you have received this e-mail by mistake and delete this e-mail from your system. E-mail transmission cannot be guaranteed to be secure or error-free as information could be intercepted, corrupted, lost, destroyed, arrive late or incomplete, or contain viruses. The sender therefore does not accept liability for any loss or damage caused by viruses or errors or omissions in the contents of this message, which arise as a result of e-mail transmission. [FriendFinder Networks, Inc., 220 Humbolt court, Sunnyvale, CA 94089, USA, FriendFinder.com -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/mysql?unsub...@msdlg.com -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/mysql?unsub=arch...@jab.org
