获取过程中的自相关性弄乱了内容

Question

我正在处理核心数据中的一个烦人的问题我有一个名为 Character 的表，它是由 如下

我正在按各个步骤填写表格：
1）填充表的属性
2）填写字符关系（charRel）

仅供参考，charRel定义如下

I' m 通过从 xml 中提取数据来提供内容， 馈送代码就是这样的

curStr = [[NSMutableString stringWithString:[curStr stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]]] retain];
NSLog(@"Parsing relation within these keys %@, in order to get'em associated",curStr);
NSArray *chunks = [curStr componentsSeparatedByString: @","];

for( NSString *relId in chunks ) {
    NSLog(@"Associating %@ with id %@",[currentCharacter valueForKey:@"character_id"], relId);
    NSFetchRequest *request = [[NSFetchRequest alloc] init];
    NSPredicate *predicate = [NSPredicate predicateWithFormat:@"character_id == %@", relId];
    [request setEntity:[NSEntityDescription entityForName:@"Character" inManagedObjectContext:[self managedObjectContext] ]];
    [request setPredicate:predicate];

    NSerror *error = nil;
    NSArray *results = [[self managedObjectContext] executeFetchRequest:request error:&error];

    // error handling code
    if(error != nil)
    {
    NSLog(@"[SYMBOL CORRELATION]: retrieving correlated symbol error: %@", [error localizedDescription]);
    } else if([results count] > 0) {
    Character *relatedChar = [results objectAtIndex:0]; // grab the first result in the stack, could be done better!
    [currentCharacter addCharRelObject:relatedChar];

    //VICE VERSA RELATIONS
    NSArray *charRels = [relatedChar valueForKey:@"charRel"];
    BOOL alreadyRelated = NO;
    for(Character *charRel in charRels) {
        if([[charRel valueForKey:@"character_id"] isEqual:[currentCharacter valueForKey:@"character_id"]])    
        {
        alreadyRelated = YES;
        break;
        }
    }

    if(!alreadyRelated)
    {
        NSLog(@"\n\t\trelating %@ with %@", [relatedChar valueForKey:@"character_id"], [currentCharacter valueForKey:@"character_id"]);
        [relatedChar addCharRelObject:currentCharacter];
    }

    } else {
    NSLog(@"[SYMBOL CORRELATION]: related symbol was not found! ##SKIPPING-->");
    }
    [request release];
}

NSLog(@"\t\t### TOTAL OF REALTIONS FOR ID %@: %d\n%@", [currentCharacter valueForKey:@"character_id"], [[currentCharacter valueForKey:@"charRel"] count], currentCharacter);

error = nil;
/* SAVE THE CONTEXT */
if (![managedObjectContext save:&error]) {
    NSLog(@"Whoops, couldn't save the symbol record: %@", [error localizedDescription]);
    NSArray* detailedErrors = [[error userInfo] objectForKey:NSDetailedErrorsKey];
    if(detailedErrors != nil && [detailedErrors count] > 0) {
    for(NSError* detailedError in detailedErrors) {
        NSLog(@"\n################\t\tDetailedError: %@\n################", [detailedError userInfo]);
    }
    }
    else {
    NSLog(@"  %@", [error userInfo]);
    }
}

当我打印出 currentCharacter 的值时， ，一切看起来都很完美。每一种关系都各就其位。 在此日志的示例中，我们可以清楚地看到该元素在 charRel 中有 3 个项目：

<Character: 0x5593af0> (entity: Character; id: 0x55938c0 <x-coredata://67288D50-D349-4B19-B7CB-F7AC4671AD61/Character/p86> ; data: {
    catRel = "<relationship fault: 0x9a29db0 'catRel'>";
    charRel =     (
        "0x9a1f870 <x-coredata://67288D50-D349-4B19-B7CB-F7AC4671AD61/Character/p74>",
        "0x9a14bd0 <x-coredata://67288D50-D349-4B19-B7CB-F7AC4671AD61/Character/p109>",
        "0x558ba00 <x-coredata://67288D50-D349-4B19-B7CB-F7AC4671AD61/Character/p5>"
    );
    "character_id" = 254;
    examplesRel = "<relationship fault: 0x9a29df0 'examplesRel'>";
    meaning = "\n  Left";
    pinyin = "\n  zu\U01d2";
    "pronunciation_it" = "\n  zu\U01d2";
    strokenumber = 5;
    text = "\n  \n    <p>The most ancient form of this symbol";
    unicodevalue = "\n  \U5de6";
})

然后，当我需要检索该项目时，我执行提取，如下所示：

// at first I get the single Character record
NSFetchRequest *request = [[NSFetchRequest alloc] init];
NSError *error;
NSPredicate *predicate = [NSPredicate predicateWithFormat:@"character_id == %@", self.char_id ];
[request setEntity:[NSEntityDescription entityForName:@"Character" inManagedObjectContext:_context ]];
[request setPredicate:predicate];
NSArray *fetchedObjs = [_context executeFetchRequest:request error:&error];

例如，当我在 NSLog 中打印出内容时charRel

NSArray *correlations = [singleCharacter valueForKey:@"charRel"];
NSLog(@"CHARACTER OBJECT \n%@", correlations);

我得到了这个

Relationship fault for (<NSRelationshipDescription: 0x5568520>), name charRel, isOptional 1, 
isTransient 0, entity Character, renamingIdentifier charRel, validation predicates (), warnings (), 
versionHashModifier (null), destination entity Character, inverseRelationship (null), minCount 1, 
maxCount 99 on 0x6937f00

希望，我已经说清楚了。
这件事让我发疯，我用谷歌搜索了世界各地，但是
我找不到解决方案（这让我想到与错误编码相关的问题：P）。

提前谢谢你们。
k

Answer 1

在对托管对象进行更改之后、保存上下文之前尝试使用 [managementObjectContext processPendingChanges];。

Answer 2

好的，我解决了这个问题，
这个问题与一些事实有关：

1）关系必须是相反的，否则系统会由于某些（未知）原因而搞乱一切。 [如下图]

2) 为了让这个模型正常工作，将东西保存在真实中方式，我添加了

[managedObjectContext refreshObject:relatedChar mergeChanges:YES];

并且

[managedObjectContext processPendingChanges];
[managedObjectContext refreshObject:currentCharacter mergeChanges:YES];