title: Grouping hive rows in an array of this rows
body: <p>I have a table like the following :</p>
  
  <pre><code>User:String Alias:String
  JohnDoe     John
  JohnDoe     JDoe
  Roger       Roger
  </code></pre>
  
  <p>And I would like to group all the aliases of an user in an array, in a new table which would look like this :</p>
  
  <pre><code>User:String Alias:array&lt;String&gt;
  JohnDoe     [John, JDoe]
  Roger       [Roger]
  </code></pre>
  
  <p>I can't figure out how to do that with HiveQL.Do I have to write an UDF for that ?</p>
  
  <p>Thanks !</p>