title: difference between thashoutput/input and tbufferoutput/input in Talend
body: <p>I don't clearly understand the difference between using tHash and tBuffer components in Talend.  </p>
  
  <p>I am looking at storing the result of a tMap in Impala table and also another copy in memory (cache) and perform other transformations on this to finally write to a table.</p>