To Many Relationship in Core Data - objective-c

Question

This is my GeneratedCode for Core data, automatically generated by xCode Editor.
#import <Foundation/Foundation.h>
#import <CoreData/CoreData.h>
#class Building, Category, City, District, Image, LatitudeLongitude, OpeningHour, Promotion, Rating, Review, URL;
#interface Business : NSManagedObject {
#private
}
#property (nonatomic, retain) NSString * Website;
#property (nonatomic, retain) NSString * Email;
#property (nonatomic, retain) NSString * Street;
#property (nonatomic, retain) NSString * InBuildingAddress;
#property (nonatomic, retain) NSString * Phone;
#property (nonatomic, retain) NSString * Title;
#property (nonatomic, retain) NSString * Zip;
#property (nonatomic, retain) NSNumber * Price;
#property (nonatomic, retain) NSSet* Promotions;
#property (nonatomic, retain) Building * Building;
#property (nonatomic, retain) NSSet* Categories;
#property (nonatomic, retain) LatitudeLongitude * LatitudeLongitude;
#property (nonatomic, retain) NSSet* Images;
#property (nonatomic, retain) OpeningHour * OpeningHour;
#property (nonatomic, retain) NSSet* Reviews;
#property (nonatomic, retain) NSSet* URLs;
#property (nonatomic, retain) Rating * Rating;
#property (nonatomic, retain) NSSet* Districts;
#property (nonatomic, retain) City * City;
//I added these 3 lines, why not part of automatically generated Code?
- (void)addDistrictsObject:(District *)value;
- (void)addCategoriesObject:(Category *)value;
- (void)addReviewsObject:(Review *)value;
#end
Say I want to "clear" all Reviews and image.
Will doing self.Reviews=nil do the trick?
I know that doing self.LatitudeLongitude=nil will delete the relationship between self and it's LatitutudeLongitude.

Answer 1

EDIT - Not sure if you mean "clear" as in delete. My answer below is assuming that you want the objects gone from the context; not just severing the relationship between the NSManagedObjects
I don't believe
self.Reviews = nil;
will actually delete your Review objects for the Managed Object Context. That would send the release message to each one, but to delete them from the context you have to call
[aContext deleteObject:reviewObj];
on each one in the set. If you were to delete one of your Business objects (using "deleteObject" as shown above) and you had your relationship delete rules set to "Cascade", then I believe that would cause all of the Review, City, etc... objects owned by that Business object to be deleted automatically, but that is the only other way that I know of that will cause NSManagedObjects to be deleted.