title: Crystal Reports Optional parameter
body: <p>I need to display data from column <strong>"user_id"</strong> which is a main column and column <strong>"pocket"</strong>. User can have <strong>many</strong> pockets. My input parameters are <strong>*user_id</strong> and <strong>pocket_id</strong>. </p>
  
  <p><strong>User_id</strong> is mandatory and if there is <strong>no pocket_id</strong> in input parameter report should display all <strong>user_id</strong> pockets. But if ther is particular <strong>pocket_id</strong> report should display user_id and pocket_id from input parameters. </p>
  
  <p>And I should do it without hasValue parameters because its return error in my database. and if I use is null construction data isn't complete. </p>
  
  <p>my current code is:</p>
  
  <pre><code>If isnull{?Pocket ID} then {PocketID}else {?Pocket ID}
  </code></pre>
  
  <p>Thank you in advance</p>