title: EntityDataSource: TotalRowCount returns -1. What's that?
body: <p>I have an EntityDataSource with <code>OnSelected</code> event (fired after finished query). The event handler has event args of type <code>EntityDataSourceSelectedEventArgs e</code>. Query runs fine without error and the IEnumerable <code>e.Results</code> contains 1 object (I can run through a non-empty foreach-loop) but <code>e.TotalRowCount</code> returns <code>-1</code>.</p>
  
  <p>Does somebody have an idea what this means and what information <code>TotalRowCount</code> actually expresses? How can I determine the number of selected objects if not by using <code>TotalRowCount</code>?</p>