title: SSRS - Look up field in dataset that is not part of report
body: <p>I have an ID column in a table in my Reporting Services report.  I want to title each page of my report based on a corresponding name field.  </p>
  
  <p>When I try to create an expression for the group-level PageName property, I see that there is a Lookup() function in SSRS.  The example given in the description looks like this:</p>
  
  <pre><code>=Lookup(Fields!SaleProdId.Value, Fields!ProductID.Value,  Fields!Name.Value, "Product")
  </code></pre>
  
  <p>The problem is that these fields are presumably in the same dataset used to create the report table.  In my case, however, the name field is in another dataset of my project.</p>
  
  <p>Is there a way to span report datasets to lookup up a label not in the current table's dataset?</p>