Core Data Relationships cause save error after delete

Question

This question is probably a long shot. I can't figure out the errors I'm getting on my core data project when I save after I delete an entity.

I have two main entities that I work with, an Outfit, and an Article. I can create them with no problem but when I delete them I get the follow error log:

For the Outfit:

2009-09-22 20:17:37.771 itryiton[29027:20b] Operation could not be completed. (Cocoa error 1600.)
2009-09-22 20:17:37.773 itryiton[29027:20b]   {
    NSLocalizedDescription = "Operation could not be completed. (Cocoa error 1600.)";
    NSValidationErrorKey = outfitArticleViewProperties;
    NSValidationErrorObject = <Article: 0x12aa3c0> (entity: Article; id: 0x12b49a0 <x-coredata://7046DA47-FCE1-4E21-8D7B-E532AAC0CC46/Article/p1> ; data: {
    articleID = 2009-09-22 19:05:19 -0400;
    articleImage = 0x12b4de0 <x-coredata://7046DA47-FCE1-4E21-8D7B-E532AAC0CC46/ArticleImage/p1>;
    articleType = nil;
    attributeTitles = "(...not nil..)";
    color = nil;
    comment = nil;
    dateCreated = 2009-09-22 19:05:19 -0400;
    designer = nil;
    imageView = "(...not nil..)";
    location = "(...not nil..)";
    outfitArticleViewProperties =     (
        0x12b50f0 <x-coredata://7046DA47-FCE1-4E21-8D7B-E532AAC0CC46/OutfitArticleViewProperties/p1>
    );
    ownesOrWants = 0;
    pattern = nil;
    price = nil;
    retailer = nil;
    thumbnail = "(...not nil..)";
    washRequirements = nil;
    wearableSeasons = nil;
});
    NSValidationErrorValue =     {(
        <OutfitArticleViewProperties: 0x1215340> (entity: OutfitArticleViewProperties; id: 0x12b50f0 <x-coredata://7046DA47-FCE1-4E21-8D7B-E532AAC0CC46/OutfitArticleViewProperties/p1> ; data: {
    article = 0x12b49a0 <x-coredata://7046DA47-FCE1-4E21-8D7B-E532AAC0CC46/Article/p1>;
    articleViewPropertiesID = nil;
    outfit = nil;
    touch = nil;
    view = "(...not nil..)";
})
    )};
}

And if I delete an Article I get:

2009-09-22 18:58:38.591 itryiton[28655:20b] Operation could not be completed. (Cocoa error 1560.)
2009-09-22 18:58:38.593 itryiton[28655:20b]   DetailedError: {
    NSLocalizedDescription = "Operation could not be completed. (Cocoa error 1600.)";
    NSValidationErrorKey = articleImage;
    NSValidationErrorObject = <Article: 0x12aa340> (entity: Article; id: 0x12b3f10 <x-coredata://05340FA6-B5DC-4646-A5B4-745C828C73C3/Article/p1> ; data: {
    articleID = 2009-09-22 18:58:26 -0400;
    articleImage = 0x12b4d00 <x-coredata://05340FA6-B5DC-4646-A5B4-745C828C73C3/ArticleImage/p1>;
    articleType = nil;
    attributeTitles = "(...not nil..)";
    color = nil;
    comment = nil;
    dateCreated = 2009-09-22 18:58:26 -0400;
    designer = nil;
    imageView = "(...not nil..)";
    location = "(...not nil..)";
    outfitArticleViewProperties =     (
        0x12b5010 <x-coredata://05340FA6-B5DC-4646-A5B4-745C828C73C3/OutfitArticleViewProperties/p1>
    );
    ownesOrWants = 0;
    pattern = nil;
    price = nil;
    retailer = nil;
    thumbnail = "(...not nil..)";
    washRequirements = nil;
    wearableSeasons = nil;
});
    NSValidationErrorValue = <ArticleImage: 0x12ad600> (entity: ArticleImage; id: 0x12b4d00 <x-coredata://05340FA6-B5DC-4646-A5B4-745C828C73C3/ArticleImage/p1> ; data: {
    article = 0x12b3f10 <x-coredata://05340FA6-B5DC-4646-A5B4-745C828C73C3/Article/p1>;
    image = "(...not nil..)";
});
}

A 1600 error is:

NSValidationRelationshipDeniedDeleteError
Error code to denote some relationship
with delete rule NSDeleteRuleDeny is
non-empty.

Available in Mac OS X v10.4 and later.

Declared in CoreDataErrors.h.

But I can't see for the life of me which relationship would be preventing the delete. If some Core Data wizard can see the error of my ways, I would be humbled.

I can't mark this solved, because I didn't really solve it, but I do have a working work-around. In the .m for each of my managedObjects I added a method that looks like:

-(void) deleteFromManangedObjectContext{ 
   self.outfit = nil; 
   self.article = nil; 
   [[self managedObjectContext] deleteObject:self]; 
} 

So you can see, first I manually nil out the relationships, and then I have the object delete itself. In other objects, instead of nil-ing, my delete method is called on some of the objects relationships, to get a cascade.

Answer 1

I just had the problem of delete fail, and landed on this question. And I've figured out my problem and thought that I'd share that too and maybe someone will have the same problem as well.

The mistake I made is that the object (A) I am trying to delete have a relationship to another object (B) with NULL as delete rule. However, object B also have a relationship to A and it's non-optional. Therefore, when I delete A, B's relationship of A becomes null which is not allowed. When I change the delete rule to cascade and it worked.