title: REPORT -Visual Studio 2012
body: <p>I am new to report.Dataset patient is a dropdownlist.Here I want to add a NULL field so thaT if i select Null it must retrieve some values from database.How can i create a NULL field in The dropdownbox of a report as below.But it is not working for me
  <a href="http://msprojectnow.com/blog/reports-in-ssrs-with-multi-value-parameters-and-null-values" rel="nofollow">http://msprojectnow.com/blog/reports-in-ssrs-with-multi-value-parameters-and-null-values</a></p>