Fixing an error...

I've jsut converted my a column in my MySQL database to date format, from text. All good, but it's over written the previous entries... (I'm left with 0000-00-00 many times) is there any roll back function to save my data? I know I should've backed up forst, but I fotgot, I@ll slap myself later, but for now, what can I do...? *********************************************************************** The information contained in this e-mail message is intended only for the personal and confidential use of the recipient(s) named above. If the reader of this message is not the intended recipient or an agent responsible for delivering it to the intended recipient, you are hereby notified that you have received this document in error and that any review, dissemination, distribution, or copying of this message is strictly prohibited. If you have received this communication in error, please notify us immediately by e-mail, and delete the original message. ************************************************************************