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SOLVED: Should the .externalStorage attribute work with a SwiftData model property that is an array of optional data?

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In my SwiftData model I have a property that is an optional array of images stored as data.

I thought by using the syntax @Attribute(.externalStorage) var imagesData: [Data]? the data would be stored external to the SwiftData database. It is not. I have inspected the containing entity (using the Core Data Lab app) and have observed the data is not stored externally.

Am I using the correct syntax?

I have confirmed with a property that is not an array (@Attribute(.externalStorage) var imagesData: Data?) that its data is stored externally as expected.

What is the correct approach when trying to saving an array of images within a SwiftData entity?

@Model class Item {
   var text: String = ""
   var date: Date = Date.now

   @Attribute(.externalStorage) var imagesData: [Data]?

   init(text: String, date: Date) {
      self.text = text
      self.date = date
   }

2      

I am assuming the answer to my question above is "no" and I used an incorrect data model.

I updated my project to add an additional model for PhotoData as shown below. This seems to work and does feel like a better approach. Not to mention, it works. Posting this followup in case others, like me, new to some of these concepts are tripping on the same and find this thread.


@Model class Item {
   var text: String = ""
   var date: Date = Date.now

   @Relationship(deleteRule: .cascade, inverse: \PhotoData.item) var photosData: [PhotoData]? = [PhotoData]()

   init(text: String, date: Date) {
      self.text = text
      self.date = date
   }
}

@Model class PhotoData {
   var id: UUID = UUID()
   @Attribute(.externalStorage) var photoData: Data?

   @Relationship(deleteRule: .nullify) var item: Item?

   init(photoData: Data) {
      self.id = UUID()
      self.photoData = photoData
   }
}

2      

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