Как показать повторяющееся значение даты, как ноль в SQL Server?

Question

У меня есть SQL-запрос

SELECT DISTINCT DENSE_RANK() 
                OVER(ORDER BY bsContract.ContractNumber DESC) AS RANKS,
       ROW_NUMBER() 
            OVER(PARTITION BY bsContract.ContractNumber ORDER BY bsContract.ContractNumber) 
         AS RowsNumber,
       dbo.bsContract.ContractNumber,
       Advertiser.OrganizationName AS Advertiser,
       JobName AS Campaign,
       bsContract.FromDate AS StartDate,
       Advertiser.OrganizationName AS Client,
       (ISNULL(bsContract.FirstName, '') + ' ' +
               bsContract.LastName) AS ClientRep,
       Advertiser.OrganizationName AS Vendor,
       (ISNULL(bsContract.FirstName, '') + ' ' +
               bsContract.LastName) AS 'VendorRep',
               DocumentType,
               FileType
   INTO #temp
   FROM dbo.bsContract     
  INNER JOIN Organization AS Advertiser
     ON Advertiser.OrganizationID = bsContract.OrganizationID
  WHERE FileType IS NULL
    AND bsContract.ContractNumber = 'CR6520'
    AND bsDocument.SellerID = 3632

   SELECT DISTINCT Ranks,
                   (CASE
                     WHEN RowsNumber = 1 THEN
                      ContractNumber
                     ELSE
                      ''
                   END) AS ContractNumber,
                   (CASE
                     WHEN RowsNumber = 1 THEN
                      Advertiser
                     ELSE
                      ''
                   END) AS Advertiser,
                   (CASE
                     WHEN RowsNumber = 1 THEN
                      Campaign
                     ELSE
                      ''
                   END) AS Campaign,
                   (CASE
                     WHEN RowsNumber = 1 THEN
                      StartDate
                     ELSE
                      (select convert(datetime, NULL))
                   END) AS StartDate,
                   Vendor,
                   VendorRep
           FROM #temp
          ORDER BY ContractNumber DESC

Все хорошо, это дает результат.В первой строке указано значение Contract Number, Advertiser Campaign, StartDate, Vendor and Vendor Rep.. Во 2-й строке значение ContractNumber, Advertiser, Campaign, StartDate совпадает, поэтому отображается как пустое.Но первая строка результата отображается дважды из-за Различного StartDate.См. Прикрепленный скриншот:

Как решить эту проблему?