title: Pentaho reporting with dropdown parameter
body: <p>I am creating a report with PDI as a datasource, now i need to use a drop down parameter in my report.
  for that i have added a JDBC datasource and wrote a SELECT sql that contains my dropdown list values and referred it in my parameter. but when i publish my report it says 'the query is not executable.' (If i change the parameter to a text box and my report works fine)</p>
  
  <p>I have tried using another transformation with the same sql as a table input but the report still not opening and says 'Error -1'.</p>
  
  <p>Report designer version: 3.6;
  Kettle version: 4.3;</p>
  
  <ol>
  <li>How can i use a dropdown parameter when i use a PDI datasource?</li>
  <li>Is it possible to add multiple datasources and use in a single report like a PDI and JDBC?</li>
  <li>or any other way to get a drop down parameter without bothering about datasources?</li>
  </ol>
  
  <p>I have googled and not able to find any solution.</p>