核心数据中实体索引的问题 [英] Questions on Index of Entity in Core Data

问题描述

1）当输入数据并且不需要输入数据时，点击实体的索引属性会自动创建该属性的索引。

1) Does clicking index property of an entity automatically creates index of that property as the data is entered and its not required to enter the index ??

2）如果从中间删除一个条目，例如索引号为3，则新的索引将为0 1 2 4 5 6 ..或者它将更新为0 1 2 3 4 5 ... ??

2) If an entry is removed from the middle, for example with index no 3 .. then will the new indices will be 0 1 2 4 5 6 .. or will it update itself to 0 1 2 3 4 5 ... ??

3）如何删除单个条目，例如.. row ID 3 ??

3) How to remove single entry for say.. row ID 3 ??

4）如何编辑提前在任何ID为

4) How to edit an existing entry at any ID ??

thnx的现有条目; ）

thnx in advance ; )

推荐答案

1）索引由Core Data自动处理。你不要做任何事情。

1) The indexing is handled automatically by Core Data. You don't do anything with it.

2）不知道，不关心，因为Core Data处理它。

2) Don't know, don't care because Core Data handles it.

别。核心数据不是SQl的包装器，不关心表和行。 Core Data使用对象。当您删除对象时，Core Data会将其从商店中删除。

3) You don't. Core Data is not a wrapper for SQl and does not concern itself with tables and rows. Core Data uses objects. When you delete a object Core Data removes it from the store.

4）通过编辑特定托管对象的属性来编辑数据。

4) You edit data by editing the properties of a specific managed object.

核心数据不是SQL。实体不是表。对象不是行。列不是属性。核心数据是一个对象图管理系统，可以或不可以持久化对象图，并且可能或可能不使用远在幕后的SQL来这样做。试图以SQL术语思考核心数据将使您完全误解核心数据，并导致很多悲伤和浪费时间。

Core Data is not SQL. Entities are not tables. Objects are not rows. Columns are not attributes. Core Data is an object graph management system that may or may not persist the object graph and may or may not use SQL far behind the scenes to do so. Trying to think of Core Data in SQL terms will cause you to completely misunderstand Core Data and result in much grief and wasted time.

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