title: How to get Sum of Special fields?
body: <p>I have a report with a table, and the table have multy fields.(Id,Name,Peyment,Type)</p>
  
  <p>I want get sum of Peyment where Type is "1".</p>
  
  <p>How to get sum of value whit special type?</p>
  
  <p>I use </p>
  
  <pre><code>{SumI(Table.Payment,Table.Id='1')}
  </code></pre>
  
  <p>and this</p>
  
  <pre><code>{IIF(Table.Type=='1',SumI(Table.Payment),0)}
  </code></pre>
  
  <p>but i get error.</p>