title: Sql Join and Sum
body: <p>I'm trying to sum an amount from two different tables using a left join.  I need all rows returned regardless of whether or not there is a match on the second table.      </p>
  
  <pre><code>   SELECT l.tender, 
            l.starting+SUM(t.amount) AS 'amount' 
       FROM label l 
  LEFT JOIN transfers t on l.tender=t.name 
   ORDER BY l.tender
  </code></pre>