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Core Data: Returning to a Previously Inserted Managed Object

I have the following model:

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Doctor <-->> Case <->> Report

A Doctor has many Cases but a Case has only one Doctor. A Case can has many Reports

I successfully generated the classes representing my model, and I inserted one Doctor, with one Case with one Report.

How can I return to this Doctor and associate another Case and the same for a Report?

Any example for one-to-many Core Data insertion and display.

best regards


When you insert a managed object you get a pointer to that object back. Assuming you have a NSManagedObject subclass of Doctor, you would create a new Doctor object like this:

Doctor *newDoc=[NSEntityDescription insertNewObjectForEntityForName:@"Doctor" 
                                               inManagedObjectContext:myManagedObjectContext];

newDoc is now a pointer to the Doctor object and you can treat it like any other object. You can retain a reference to it any way you like e.g. instance attribute, array, set etc. You can then retrieve it and add new Case object like so:

[newDoc addCaseObject:aNewCase];

...and the same to add a Report to a case. These methods are defined in the autogenerated subclasses.

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