Hello, this is not a problem with Xcode as you found out, but with the data that already exists in your database. Suppose you have 5 fields and some records in the database. You are adding a field that is NOT optional. What should happen to the records where the field is empty? However, the field cannot be empty. There are various strategies to deal with this, but I'm not sure it's easy with core data.
ChrisDE
Users receive reputation points by contributing quality content to the forums.
Posts include post and replies published on the forums.
Post authors can mark replies as Accepted to indicate successful solutions.
Apple Developer Forums admins can mark replies as Apple Recommended to indicate an approved solution