title: SQLContext implicits
body: <p>I am learning spark and scala. I am well versed in java, but not so much in scala. I am going through a tutorial on spark, and came across the following line of code, which has not been explained:</p>
  
  <pre><code>val sqlContext = new org.apache.spark.sql.SQLContext(sc)
  import sqlContext.implicits._
  </code></pre>
  
  <p>(<code>sc</code> is the SparkContext instance)</p>
  
  <p>I know the concepts behind scala implicits (atleast I think I know). Could somebody explain to me what exactly is meant by the <code>import</code> statement above? What <code>implicits</code> are bound to the <code>sqlContext</code> instance when it is instantiated and how? Are these implicits defined inside the SQLContext class?</p>
  
  <p><strong>EDIT</strong>
  The following seems to work for me as well (fresh code):</p>
  
  <pre><code>val sqlc = new SQLContext(sc)
  import sqlContext.implicits._
  </code></pre>
  
  <p>In this code just above. what exactly is sqlContext and where is it defined?</p>