title: How to get group by Alias column in Dataframe SELECT list
body: <p>I am doing SUM on multiple column, those columns want to include in the SELECT list. </p>
  
  <p>Below are my work:</p>
  
  <pre><code>val df=df0
                               .join(df1, df1("Col1")&lt;=&gt;df0("Col1"))
                               .filter((df1("Colum")==="00")
                               .groupBy(df1("Col1"),df1("Col1"))
                               .agg(sum(df1("Amount").alias("Amount1")),sum(df1("Amount2").alias("Amount2")))
                               .select(
                                           df1("Col1").alias("co11"),
                                           df1("Col2").alias("Col2"),
                                           Amount1, Amount2 --getting error here
                                            )
  </code></pre>
  
  <p>How to include the alias column in the SELECT list?</p>