Swift Way to Duplicate a Record

[bradhowes]

Newbie Q: Is there a straightforward way in Swift to duplicate an existing record? I know I could do this in SQL, but I'm interested in having a record type clone itself with the clone having a new unique ID.

[groue]

Hello @bradhowes,

If your record has an auto-incremented id, you can duplicate a record this way:

struct Player: Codable {
  var id: Int64?
  var name: String
  var score: Int
}

extension Player: FetchableRecord, MutablePersistableRecord {
  mutating func didInsert(_ inserted: InsertionSuccess) {
    id = inserted.rowID
  }
}

try dbQueue.write { db in
  // Fetch player 42
  let player = try Player.find(db, key: 42)

  // Duplicate with a new id
  var copy = player
  copy.id = nil
  try copy.insert(db)
  print(copy.id) // Some id which is not 42
}

If the id is not auto-incremented, you can duplicate a record as below:

struct Player: Codable, Identifiable {
  var id: String
  var name: String
  var score: Int
}

extension Player: FetchableRecord, PersistableRecord { }

try dbQueue.write { db in
  // Fetch player "foo"
  let player = try Player.find(db, id: "foo")

  // Duplicate into player "bar"
  var copy = player
  copy.id = "bar"
  try copy.insert(db)
}

[bradhowes]

@groue Thanks for your assistance. Makes perfect sense. For some reason, I was not seeing that completion. But that is happening to me a lot in Xcode.