Mongoose mengembalikan objek penuh setelah memasukkan data ke DB
var instance = new TestingModel()
console.log(instance._id) // => 4e7819d26f29f407b0...
Vishnu
var instance = new TestingModel()
console.log(instance._id) // => 4e7819d26f29f407b0...var instance = new TestingModel()
instance.test = 'blah'
instance.save(function(err){
console.log(instance._id) // => 4e7819d26f29f407b0...
})