Creating a unique id for a Core Data program on the iPhone

iphone cocoa-touch core-data
user165411 picture user165411 · Aug 29, 2009 · Viewed 49.6k times · Source

I am having a bit of trouble figuring out this Core Data stuff. How do I create a new entry with a unique ID? In SQL I would just declare one field as an autoincrement field. I'm not seeing anything like that here, but I could just be missing something. I just want an auto incrementing NSInteger field, so when I manually add items to the database, I will have some form of reference to them.

Answer

user142764 picture user142764 · Jan 24, 2010

Though i agree with what you said, there is an ID mechanism behind core data. ID are indeed managed by Core-Data but you can retrieve them with :

NSManagedObjectID *moID = [managedObject objectID];

For more informations see : Core Data Programming Guide

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