How to dyanmic create a new entity (table) via CoreData model?

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南笙
南笙 2021-02-10 00:01

I want to create a new Entity (table) in SQLite. My code is as follows:

+(BOOL)CreateDataSet:(NSManagedObjectModel *) model  
    attributes:(NSDictionary*)attri         


        
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  •  轻奢々
    轻奢々 (楼主)
    2021-02-10 00:40

    I quote Apple's Documentation which describes it very accurately:

    Entity descriptions are editable until they are used by an object graph manager. This allows you to create or modify them dynamically. However, once a description is used (when the managed object model to which it belongs is associated with a persistent store coordinator), it must not (indeed cannot) be changed. This is enforced at runtime: any attempt to mutate a model or any of its sub-objects after the model is associated with a persistent store coordinator causes an exception to be thrown. If you need to modify a model that is in use, create a copy, modify the copy, and then discard the objects with the old model.

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