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

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轮回少年
轮回少年 2021-02-09 23:59

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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  •  离开以前
    2021-02-10 00:41

    From the documentation for NSManagedObjectModel:

    Editing Models Programmatically

    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.

    In other words, edit your managed object model before you set up your persistent store coordinator or managed object context.

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