为什么存储过程结果为零？

 exec spGetInvoiceByDate '03/01/2011 00:00:00 AM','03/31/2011 11:59:59 PM'

create procedure [spGetInvoiceByDate]  
  @Beginning_Date DateTime, @Ending_Date DateTime  
as  
begin  

SELECT * INTO #temp1 FROM (  
SELECT     convert(varchar, ManifestPort.StartDate, 1)+'-'+CASE dbo.ManifestPort.EndDate WHEN '1800-01-01 00:00:00.000' THEN 'N/A' ELSE convert(varchar, ManifestPort.EndDate, 1) END AS [Date], Manifest.VesselName, Manifest.VoyageNo, DischargePort.PortName
, ManifestPort.Terminal, COUNT(Seal.ContainerNo) TotalContainers, 0 AS TotalHours, 0 AS TotalFee  
FROM ManifestPort 
INNER JOIN Manifest ON ManifestPort.ManifestNo = Manifest.ManifestNo 
INNER JOIN DischargePort ON ManifestPort.PortCode = DischargePort.PortCode 
INNER JOIN Seal ON ManifestPort.ManifestPortNo = Seal.ManifestPortNo  
WHERE (StartDate BETWEEN @Beginning_Date AND @Ending_Date)                
GROUP BY StartDate,EndDate, VesselName, VoyageNo, PortName, Terminal) AS a  

SELECT * INTO #temp2 FROM (  
SELECT convert(varchar, ManifestPort.StartDate, 1)+'-'+CASE dbo.ManifestPort.EndDate WHEN '1800-01-01 00:00:00.000' THEN 'N/A' ELSE convert(varchar, ManifestPort.EndDate, 1) END AS [Date], Manifest.VesselName, Manifest.VoyageNo, DischargePort.PortName, 
ManifestPort.Terminal, COUNT(Seal.ContainerNo) STotalContainers, 0 AS STotalHours, 0 AS STotalFee  
FROM ManifestPort 
INNER JOIN Manifest ON ManifestPort.ManifestNo = Manifest.ManifestNo 
INNER JOIN DischargePort ON ManifestPort.PortCode = DischargePort.PortCode 
INNER JOIN Seal ON ManifestPort.ManifestPortNo = Seal.ManifestPortNo  
WHERE (StartDate BETWEEN @Beginning_Date AND @Ending_Date ) AND Line = 'CSAV'  
GROUP BY StartDate,EndDate, VesselName, VoyageNo, PortName, Terminal     ) AS b  

SELECT  #temp1.Date,  
        #temp1.VesselName ,  
        #temp1.VoyageNo ,  
        #temp1.PortName ,  
        #temp1.Terminal ,  
        #temp1.TotalContainers ,  
        #temp1.TotalHours ,  
        #temp1.TotalFee, #temp2.STotalContainers, #temp2.STotalHours, #temp2.STotalFee FROM #temp1 INNER JOIN #temp2  
        ON #temp1.Date = #temp2.Date AND #temp1.PortName = #temp2.PortName AND #temp1.Terminal = #temp2.Terminal AND #temp1.VesselName = #temp2.VesselName  
        AND #temp1.VoyageNo = #temp2.VoyageNo  

        Order BY #temp1.VesselName, #temp1.VoyageNo  

DROP TABLE #temp1  
DROP TABLE #temp2  

end

DateTime firstDayOfMonth = Convert.ToDateTime("03/01/2011");
DateTime lastDayOfMonth = Convert.ToDateTime("03/31/2011");

var results = ProviderName.spGetInvoiceByDate(firstDayOfMonth,lastDayOfMonth);