ios - Realm Objective-C 写入数据库时​​如何忽略已经存在的相同主键？

Question

我从服务器获取数据列表。它们是一堆书。我有书、书、人的 RLMObjects。

@class Person, Book;
@interface Person : RLMObject

@property (nonatomic, strong) NSString *name;
@property (nonatomic, assign) int age;
@property (nonatomic, assign) NSInteger id;
@end
RLM_ARRAY_TYPE(Person)


@interface Book : RLMObject

@property (nonatomic, strong) Person *author;
@property (nonatomic, strong) NSString *price;
@property (nonatomic, strong) RLMArray<Person> *translators;
@end
RLM_ARRAY_TYPE(Book)


@interface Books : RLMObject

@property (nonatomic, assign) NSInteger count;
@property (nonatomic, strong) NSString *year;
@property (nonatomic, strong) RLMArray<Book> *books;
@end

@implementation Person

+ (NSString *)primaryKey {
    return @"id";
}

@end

当我获得书籍数组时，将它们从字典转换为 Books 对象。然后将其添加到 Realm 。

[[RLMRealm defaultRealm] transactionWithBlock:^{
        [[RLMRealm defaultRealm] addObject:[Books mj_objectWithKeyValues:responseObject]];
    } error:nil];

它崩溃了。因为有两本书有相同的译者。无法将主键属性“id”设置为现有值“1314331”。

那么，像这种情况，如何把数据放到RLMRealm中，并通过primaryKey保证每个person对象是唯一的呢？

Answer 1

试试这个

[[RLMRealm defaultRealm] transactionWithBlock:^{
    RLMObject *object = [Books mj_objectWithKeyValues:responseObject];
    [[RLMRealm defaultRealm] addOrUpdateObject:object];
} error:nil];