title: Does SparkSQL support subquery?
body: <p>I am running this query in Spark shell but it gives me error,</p>
  
  <pre><code>sqlContext.sql(
   "select sal from samplecsv where sal &lt; (select MAX(sal) from samplecsv)"
  ).collect().foreach(println)
  </code></pre>
  
  <p>error:</p>
  
  <blockquote>
    <p>java.lang.RuntimeException: [1.47] failure: ``)'' expected but identifier MAX found</p>
    
    <p>select sal from samplecsv where sal &lt; (select MAX(sal) from samplecsv)
                                                  ^
        at scala.sys.package$.error(package.scala:27)
    Can anybody explan me,thanks</p>
  </blockquote>