m field relation equivalences.</li>
</ul>
<p><strong>Sample</strong></p>
<p>Imagine we are reporting sales by customer but very detailed. We will use a 
  subreport with a group, customer number, the trick is that at the group header 
  <strong>we want to print total by customer</strong>, so expression evaluator 
  sums will not work.</p>
<p>You can solve the problem by using linked querys, but this linked query will 
  be executed each time a CUSTNO changes in the main dataset, if there are 200 
  customer