Core data changes, now update is crashing

I did a grave mistake, not migrating the coredata model properly (I'm a newbe, sorry). But now my update will crash when doing a specific开发者_如何学运维 operation. I need to fix it quickly because it is already out in the app store. My data model is very simple and all I need is deleting old model and uploading new one (like, deleting the app and reinstall it). how do I do it? I know it is a stupid question, I can probably find the answer myself and learn how to do it, and I would have done that unless my bugged app had not ben already out there. Thanks in advance.

I followed the instructions here: http://iphonedevelopment.blogspot.com/2009/09/core-data-migration-problems.html

Much better than Apple's documentation... (found it in another thread in this site).

And it worked right away!