title: mongoose save 4 document for one call
body: <p>I have some issues saving datas in my mongodb using mongoose. Here is the code that i use :</p>
  
  <pre><code>var amin = new User({FirstName: "Amin",LastName: "Taghikhani"});
  amin.save(function (err, user) {
      if (err)
          throw err;
      user.SayHello();
  });
  </code></pre>
  
  <p>but mongoose save 4 document, in my database i have 4 document by </p>
  
  <pre><code>FirstName: Amin, LastName: Taghikhani
  </code></pre>
  
  <p>can anyone help me why mongoose save 4 document?!</p>
  
  <p>thank you for answer.</p>