title: How to merge map column in spark sql?
body: <p>I have two Map type columns in a Dataframe. Is there a way I can create a new Map column merging these two columns in spark Sql using .withColumn ?</p>
  
  <pre><code>val sampleDF = Seq(
   ("Jeff", Map("key1" -&gt; "val1"), Map("key2" -&gt; "val2"))
  ).toDF("name", "mapCol1", "mapCol2")
  
  sampleDF.show()
  
  +----+-----------------+-----------------+
  |name|          mapCol1|          mapCol2|
  +----+-----------------+-----------------+
  |Jeff|Map(key1 -&gt; val1)|Map(key2 -&gt; val2)|
  +----+-----------------+-----------------+
  </code></pre>