从核心数据库中获取数据时获取initWithCode ..的异常

Question

从核心数据库中获取数据时，我遇到以下异常。

我能够成功保存数据，可以在Coredatabase中看到数据。

例外：- [错误]错误：SQLCore dispatchRequest：异常处理请求：-[EntityCurrencies initWithCoder：]：无法识别的选择器发送到实例0x600001ede880，其中userInfo为（null）

我的班级结构如下。

EntityCurrencies + CoreDataProperties.swift

扩展EntityCurrencies {

@nonobjc public class func fetchRequest() -> NSFetchRequest<EntityCurrencies> {
    return NSFetchRequest<EntityCurrencies>(entityName: "EntityCurrencies")
}
@NSManaged public var name: String?
@NSManaged public var country_currency: EntityCountry?

}

EntityCountry + CoreDataProperties.swift

扩展EntityCountry {

@nonobjc public class func fetchRequest() -> NSFetchRequest<EntityCountry> {
    return NSFetchRequest<EntityCountry>(entityName: "EntityCountry")
}

@NSManaged public var currencies: [EntityCurrencies]?
@NSManaged public var languages: [EntityLanguages]?
@NSManaged public var country_currency: EntityCurrencies?
@NSManaged public var country_language: NSSet?

}

下面是获取请求代码：

 let manageObjectContext = persistentContainer.viewContext

    let request:NSFetchRequest<EntityCountry> = EntityCountry.fetchRequest()

    do {
        let result = try manageObjectContext.fetch(request) **/* Crash here */**