title: Why is there a scan on my clustered index?
body: <p>SQL 2000<br>
  The NED table has a foreign key to the SIGN table NED.RowID to SIGN.RowID<br>
  The SIGN table has a foreign key to the NED table SIGN.SignID to NED.SignID<br>
  The RowID and SignID are clustered primary keys that are GUIDs (not my choice)<br>
  The WHERE clause is:    </p>
  
  <pre><code>FROM
      [SIGN] A   
      INNER JOIN NED N ON A.SIGNID = N.SIGNID  
      INNER JOIN Wizard S ON A.WizardID = S.WizardID   
      INNER JOIN [Level] SL ON N.LevelID = SL.LevelID  
      LEFT JOIN Driver DSL ON SL.LevelID = DSL.LevelID  
          AND DSL.fsDeptID = @fsDeptID  
      INNER JOIN [Character] ET ON S.CharacterID = ET.CharacterID  
      INNER JOIN Town DS ON A.TownID = DS.TownID   
  WHERE  
      (A.DeptID = @DeptID OR   
      S.DeptID = @DeptID  
      AND   
      A.[EndTime] &gt; @StartDateTime AND A.[StartTime] &lt; @EndDateTime  
      AND   
      A.NEDStatusID = 2    
  </code></pre>
  
  <p>Why is there an INDEX SCAN on the SIGN table for this query?  What would cause an index scan on a clustered index? Thanks  </p>