// Escribir datos ref.child("users").child("userId").setValue(["name": "John", "age": 30]) // Leer datos ref.child("users").child("userId").observeSingleEvent(of: .value) { (snapshot) in if let value = snapshot.value as? [String: Any] { let name = value["name"] as? String ?? "" let age = value["age"] as? Int ?? 0 print("Name: \(name), Age: \(age)") } }