Test of searching for not saved data in core data

searching_for_not_saved_data.swift

import UIKit
import CoreData

class ViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()
        populateDatabase()
    }
    
    var context: NSManagedObjectContext {
        return (UIApplication.sharedApplication().delegate as! AppDelegate).managedObjectContext
    }

    func populateDatabase() {
        let names = ["John", "Jenny", "Sam", "Alicia", "Maggie", "Jane"]
        let ages = [21, 23, 22, 24, 19, 22, 21, 25]
        
        for (var idx = 0; idx < names.count; idx++) {
            let entity = NSEntityDescription.insertNewObjectForEntityForName("Person", inManagedObjectContext: context) as! Person
            entity.name = names[idx]
            entity.age = ages[idx]
            
            searchFor(entity.name!)
        }
    }
    
    func searchFor(name: String) {
        let fetchRequest = NSFetchRequest(entityName: "Person")
        fetchRequest.predicate = NSPredicate(format: "name == %@", name)
        let objects = try! context.executeFetchRequest(fetchRequest)
        print("results for searching for name [\(name)] = \(objects.first?.objectID)")
    }
}

// Output
results for searching for name [John] = Optional(0x79f73540 <x-coredata:///Person/tA9493D02-FF5D-4EF5-9BDF-A857487ECD292>)
results for searching for name [Jenny] = Optional(0x7a161300 <x-coredata:///Person/tA9493D02-FF5D-4EF5-9BDF-A857487ECD293>)
results for searching for name [Sam] = Optional(0x7a1627a0 <x-coredata:///Person/tA9493D02-FF5D-4EF5-9BDF-A857487ECD294>)
results for searching for name [Alicia] = Optional(0x7a164040 <x-coredata:///Person/tA9493D02-FF5D-4EF5-9BDF-A857487ECD295>)
results for searching for name [Maggie] = Optional(0x7a166130 <x-coredata:///Person/tA9493D02-FF5D-4EF5-9BDF-A857487ECD296>)
results for searching for name [Jane] = Optional(0x7a1640e0 <x-coredata:///Person/tA9493D02-FF5D-4EF5-9BDF-A857487ECD297>)