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

Answers:

Remove the app from the simulator and perform a clean on your project. That should clear those issues up. Make sure that you are not running in the debugger when you delete the app or else it won't actually delete it properly.

If you want to be sure its gone, check this directory Users/INSERT_YOUR_USER_HERE/Library/Application Support/iPhone Simulator/ for your app's folder, under the version you're running.

Note: This is for development only. For production, you need to implement some sort of migration. Google "Core Data Migration", with lightweight migration being the simplest.

When you change core data, ( adding a field to table , removing field etc ), the sqlite file in applications document folder needs to be in sync with your schema.

This file is not overwritten by default, this file needs to be regenerated. 

Follow these steps:

1. Go to the folder pointed by NSURL. (This path can be found in exception message generated by application before crashing.) example : /Users//Library/Application Support/iPhone Simulator//Applications//Documents

2. remove or rename the sqlite file 

3. Clean and Rerun the application
4. Rerunning application would generate a new sqlite file.

This will make sure that the schema and Xcode are in sync.

参考：http://stackoverflow.com/questions/8881453/the-model-used-to-open-the-store-is-incompatible-with-the-one-used-to-create-the