为什么deleteObject：会导致CoreData故障？

Question

I have a cleanup routine that purges out a bunch of managed objects, form some reason that seems to trigger a lot of CoreData faults.

NSFetchRequest *request = [[NSFetchRequest alloc] initWithEntityName:@"LogEvent"];
NSSortDescriptor *sortDescriptor = [[NSSortDescriptor alloc] initWithKey:@"id" ascending:YES];
[request setSortDescriptors:@[sortDescriptor]];
[request setFetchLimit:numberToPurge];

NSArray *events = [context executeFetchRequest:request error:nil];

for (LogEvent *event in events) {
    [context deleteObject:event];
}

[context save:nil];

This is what I see in instruments.

Answer 1

通常会触发此错误，以更新链接到已删除对象的对象上的逆关系。