How do I perform a search using SwiftData within an observable data model
For example: If I have a database of books that contains the property isbn, how would I perform a search to confirm I either had or did not have a book with the isbn I am searching for?
Using CoreData I use a fetch request:
let predicate = NSPredicate(format: "%K == %@", #keyPath(Book.isbn), isbn)
let fetchRequest: NSFetchRequest<Book> = Book.fetchRequest()
...
let book = try context.fetch(fetchRequest). // returns [book] use isEmpty for not found.
...
if book.isEmpty {
saveBook()
}
I have a number of queries I perform on the database to drive the logic within the app, this is just one example.
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