Question

I have newer version app to update to app store, but since there were some obsolete data: such as database and some files that I don’t need in the newer build or some databases which are use same name as newer build but the DB structure is different, so is there a way to remove all personal data of last version when user do the update? Then after user updated my app the app feels like a brand-new one.

Answer 1

On app start up you can simply remove the entire store file with something like this.

NSString *path = <path to your file> 
[[NSFileManager defaultManager] removeItemAtPath:[self persistentStorePath] error:nil];

You can use this code to get the path to the documents directory, if that is where you store the data.

NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES); 
NSString *path = [[[paths lastObject] stringByAppendingPathComponent:@"subdirectoryIfAny"] 
                      stringByAppendingPathComponent:@"name of your .sql or whatever"];

If you do not want to blow away all the data, then you have read in the records you want to delete and then manually remove them.