Today i’m playing around with core data. I’ve had created the model of the database and run the program, everything was ok. Than i realized that one of the relationship i had is a has many not has one so i’ve changed this relationship and re run the program… and than the crash. Console reported this error :

The model used to open the store is incompatible with the one used to create the store.

F**K. After googled a little i’ve discovered that if you do some changes to the model this error occours and to solve you have to

Delete the application from the simulato or the device you have the program installed!!!