核心数据动态实体 [英] core data dynamic entities

问题描述

我想要能够根据将在另一个实体中定义的属性创建一个动态实体。例如：

实体：Lifeform
Attribute-> name：String

实体：LifeformCharacteristics
Attribute-> name：String
Attribute-> type：String

实体：DynamicCatalog

因此，特征实体将是将由用户添加的任何内容填充的实体。示例特性可以是名称：高度类型：数字。所以这些特性定义了我想要的动态目录。因此，DynamicCatalog应使用属性Height创建。

DynamicCatalog也必须在表中可见，以便用户可以向目录添加和删除项目。

我可以通过我的DataModel构建和管理前两个实体，但第三个是动态的，我不知道如何去做。我希望使用核心数据使管理数据的头痛最小化。

这个帖子是我找到的答案最接近的，但我不知道现在显示或重组一个集合，像这样：在Core Data中创建动态模式？

考虑在Core Data中创建一个to many的DynamicCatalog类型，与称为DynamicCatalogValue的东西的关系或者一些环绕语义铃声的名称。在值上创建允许用户描述的属性。例如（pseudo）：

  DynamicValue：
属性：userGivenName; 
属性：userGivenValue; 
属性：valueType; （例如String，Date等）
  

I want to be able to create a dynamic entity based on attributes that will be defined in another entity. For example:

Entity:Lifeform Attribute->name:String

Entity:LifeformCharacteristics Attribute->name:String Attribute->type:String

Entity:DynamicCatalog

So the characteristics entity will be a entity that will be populated by whatever the user adds. An example characteristic could be name:Height type:Number. So these characteristics define what I want the dynamic catalog to be. As such the DynamicCatalog should be created with the attribute Height.

The DynamicCatalogs will also have to be visible in a table so the user can add and remove items to the catalogs.

I can build and manage the first 2 entities via my DataModel, but the 3rd is dynamic and I'm not sure how to go about it. I was hoping to use core data to keep the headache of managing data to a minimal.

This post is the closest thing I've found to an answer, but I'm not sure now to display or reorganize a collection like this: Faking a dynamic schema in Core Data?

解决方案

Why cause yourself so much trouble?

Consider creating the DynamicCatalog type in Core Data with a 'to many' relationship to something called 'DynamicCatalogValue' or some name that rings the semantic bell. Create attributes on the 'Value' that you will allow the user to describe. For example (pseudo):

DynamicValue:
Attribute: userGivenName;
Attribute: userGivenValue;
Attribute: valueType; (e.g. String, Date, etc.)

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