title: Hive join with distinct
body: <p>I have two tables TableA and TableB.</p>
  
  <p>TableA has columns REC_NUM and ITEM_ID.
  TableB has columns ITEM_ID, UNITS.</p>
  
  <p>I need to take a distinct of ITEM_ID from TableA, and fetch all the
   records from TableB for every matching value of ITEM_ID from TableA with that of the ITEM_ID of TableB.</p>
  
  <p>Can someone please let know I can do this.</p>