title: how to sum two columns at left and display total in third column
body: <p>I have a table similar to below   </p>
  
  <pre><code>Date     | institution | qty1 | qty2
  1 Aug 12 | xyz         |  0   | 5
  1 Aug 12 | xyz         |  0   | 17
  1 Aug 12 | abc         | 12   | 0
  2 Aug 12 | abc         | 33   | 0
  2 Aug 12 | xyz         | 0    | 57 
  </code></pre>
  
  <p>I want output similar to below</p>
  
  <pre><code>Date     | ABC     | XYZ  | Total
  1 Aug 12 | 12      |  22  | 34
  2 Aug 12 | 33      |  57  | 90
  Total    | 45      | 79   | 124
  </code></pre>
  
  <p>Now I have written a query which displays only first three columns. I don't know how to add the last total column</p>
  
  <pre><code>select date, sum (case when institution = 'abc', qty1 else 0 end) as ABC,
  sum(case when institution =  'xyz', qty2 else 0 end) as XYZ
  group by date
  with rollup
  </code></pre>