ModelContext has a property autosaveEnabled that you can set to false and then handle validation and save logic in a button action or something

I am not sure exactly what you are asking but as far as the ModelContainer yo must supply all your model types, directly or indirectly, when you create the container object

But Hashtag and HashtagFilter are two different models so why should their persistentModelID values be equal? Your variable naming confused me.

You should pass the id (persistentModelID), as you do in your code above, across actor boundaries and never the object itself.

where does the content of filterHashtags come from?

If I understand you correctly the issue is that you can't use the word throws in your code as an attribute name but maybe you can work around that by using backticks around it. I know this works fine for variables and properties and in custom types so hopefully it works within a Core Data/SwiftData context as well. So something like this should work, var `throws`: String

https://stackoverflow.com/a/79090346/9223839

I only use the @Relationship macro at one end of the relationship to avoid any issues. Maybe something has changed in the latest version that allows us to use it at both properties but in your case there is really no reason to do so.

Try to remove the database file so that SwiftData can generate a new one.

Looks like you need to perform a migration, see for example https://developer.apple.com/wwdc23/10195

Your model looks a bit strange to me. Why do you have a many to many relationship between the two models and why do you have an id property of type Float? Is it correct to assume that the float is the actual value (size) here and if so why is then the value also the identifier and why does each value need to be unique?

If you want to do something like this I believe you should have one ModelContainer but with multiple ModelConfiguration objects.

You have a complex and dynamic design which will make the whole solution more complex. When you write "...sort the inspections based on the values only in fields with specific labels" it not only is an example of the complexity but it is quite frankly hard to understand how/if it should work. An inspection can have many groups and a group can have many rows so even if you are only sorting on one label with a specific field it will be a complex task to sort the rows and groups for a single inspection not to mention comparing inspections. Since I have no idea what an inspection is in this context and neither what your fields will be filled with it's hard to give any kind of advice but for starters, do you really, really need to sort the inspectors in this manner?

Did you try without a custom migration, since the property has a default value it should work automatically?

It doesn't work well when all objects you want to add are new and haven't been inserted before. Try to first insert the Item object before adding the SubItem objects. For example let item = Item(name: "Item1", subitems: []) container.mainContext.insert(item) item.subitems.append(SubItem(name: "subItemA")) item.subitems.append(SubItem(name: "subItemB"))