title: Formula for Suppressing Field if duplicate in Crystal Reports
body: <p>I have a view which shows data on crystal reports where I have fields like tariff,rental,shares,gross and net.My problem is if someone changes the tariff in database it would show 2 rows of the same record with different tariff which is normal behavior from database point of view but I want to suppress the field of monthly rental to 0 if the same id has different tariff or the rental is repeated in new record.</p>
  
  <pre><code>ID  Tariff  Rental
  1    20       390
  1    15       390
  </code></pre>
  
  <p>I want the field of Rental on reports to be suppressed if duplicates based on id.Currently I have used this formula in crystal report to check previous field data and suppress if duplicate.</p>
  
  <p>{DatabaseField}=Previous({DatabaseField})</p>
  
  <p>It is working fine but if the id is not same and the rental is repeated then also it will suppress which I don't want.I want it to suppress only for same id.</p>