title: crystal reports DataSet does not support System.Nullable
body: <p><img src="https://i.stack.imgur.com/Be5s5.png" alt="enter image description here"></p>
  
  <blockquote>
    <p>Additional information: DataSet does not support System.Nullable&lt;>.</p>
  </blockquote>
  
  <p>Error in crystal report at line</p>
  
  <pre><code>rd.SetDataSource(allCustomer);
  </code></pre>