title: spark error RDD type not found when creating RDD
body: <p>I am trying to create an RDD of case class objects.  Eg., </p>
  
  <pre><code>// sqlContext from the previous example is used in this example.
  // createSchemaRDD is used to implicitly convert an RDD to a SchemaRDD.
  import sqlContext.createSchemaRDD
  
  val people: RDD[Person] = ... // An RDD of case class objects, from the previous example.
  
  // The RDD is implicitly converted to a SchemaRDD by createSchemaRDD, allowing it to be stored using        Parquet.
  people.saveAsParquetFile("people.parquet")
  </code></pre>
  
  <p>I am trying to complete the part from the previous example by giving </p>
  
  <pre><code>    case class Person(name: String, age: Int)
  
      // Create an RDD of Person objects and register it as a table.
      val people: RDD[Person] = sc.textFile("/user/root/people.txt").map(_.split(",")).map(p =&gt; Person(p(0), p(1).trim.toInt))
      people.registerAsTable("people")
  </code></pre>
  
  <p>I get the following error:</p>
  
  <pre><code>&lt;console&gt;:28: error: not found: type RDD
         val people: RDD[Person] =sc.textFile("/user/root/people.txt").map(_.split(",")).map(p =&gt; Person(p(0), p(1).trim.toInt))
  </code></pre>
  
  <p>Any idea on what went wrong?
  Thanks in advance!</p>