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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  •  难免孤独
    2021-02-10 00:30

    From the documentation: (emphasis is mine)

    Managed object models are editable until they are used by an object graph manager (a managed object context or a persistent store coordinator). This allows you to create or modify them dynamically. However, once a model is being used, it must not be changed. This is enforced at runtime—when the object manager first fetches data using a model, the whole of that model becomes uneditable. Any attempt to mutate a model or any of its sub-objects after that point 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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