title: Can't marshal string as a BSON document error in Golang mongo driver
body: <p>I am trying to read some data from MongoDB in go using <strong>gopkg.in/mgo.v2</strong> driver. i have written the following code to extract the information form MongoDB.   </p>
  
  <p>my go struct</p>
  
  <pre><code>type NetworkUser struct {
      Id         bson.ObjectId   `bson:"_id,omitempty"        json:"-"`
      FirstName  string          `bson:"firstName"            json:"firstName"`
      MiddleName string          `bson:"middleName,omitempty" json:"middleName,omitempty"`
      LastName   string          `bson:"lastName"             json:"lastName"`
      Inserted   time.Time       `bson:"inserted"             json:"-"`
  }
  </code></pre>
  
  <p>then, i have written the following code for reading from the mongo</p>
  
  <pre><code>//Connect to the Collection and Execute query
  _collection := _session.DB(database).C(collection)
  
  //Executing the query 
  var results []NetworkUser
  err = _collection.Find(query).All(&amp;results)
  
  //Handle the errors
  if err != nil {
      fmt.Println(err)
      panic(err)
  }
  </code></pre>
  
  <p>When i run the code, i am getting the following error : <strong>Can't marshal string as a BSON document</strong></p>
  
  <p>Please let me know, if anyone come across this error and how to fix it..</p>