Question

I have an iphone app that has a sqlite db, mapped to core data. All the data manipulation in the app is via Coredata.

On one table I wanted to add a string attribute. And I did two things both with similar crashes:

1. I tried to use Mesasql to alter the structure. I easily added a Varchar column. But it crashes.

2. On a separate attempt, with the mapped SQLlite db, restored, I tried adding a attribute to the entity in core data and it crashed.

This is the error I got:
* Terminating app due to uncaught exception of class ‘NSCFString’
terminate called after throwing an instance of ‘NSCFString’

So, how can I alter the structure of the sqlite table mapped to core data without breaking the app? Am I fogetting to do a commit or something like that?

Please help

Answer 1

Every time you modify an entity you have to delete the sqlite store. If your application has already shipped, the alternative is to migrate your data. This SO answer offers a simple explanation of how to do that.