SQL查询产生重复行，我看不出为什么

我的查询总是产生重复的结果。如何使用数据库> 100万行解决此查询的最佳做法。SQL查询产生重复行，我看不出为什么

Select segstart 
    ,segment 
    ,callid 
    ,Interval 
    ,dialed_num 
    ,FiscalMonthYear 
    ,SegStart_Date 
    ,row_date 
    ,Name 
    ,Xferto 
    ,TransferType 
    ,Agent 
    ,Sup 
    ,Manager 
    ,'MyCenter' = Case Center 
When 'Livermore Call Center' Then 'LCC' 
When 'Natomas Call Center' Then 'NCC' 
When 'Concord Call Center' Then 'CCC' 
When 'Virtual Call Center' Then 'VCC' 
When 'Morgan Hill Call Center' Then 'MHCC' 
Else Center 
End 
    ,Xferfrom 
    ,talktime 
    ,ANDREWSTABLE.transferred 
    ,ANDREWSTABLE.disposition 
    ,dispsplit 
    ,callid 
    ,hsplit.starttime 
    ,CASE 
    WHEN hsplit.callsoffered > 0 
    THEN (CAST(hsplit.acceptable as DECIMAL)/hsplit.callsoffered)*100 
    ELSE '0' 
    END AS 'Service Level' 
    ,hsplit.callsoffered 
    ,hsplit.acceptable 
FROM 
(
Select segstart, 
    100*DATEPART(HOUR, segstart) + 30*(DATEPART(MINUTE, segstart)/30) as Interval, 
    FiscalMonthYear, 
    SegStart_Date, 
    dialed_num, 
    callid, 
    Name, 
    t.Queue AS 'Xferto', 
    TransferType, 
    RepLName+', '+RepFName AS Agent, 
    SupLName+', '+SupFName AS Sup, 
    MgrLName+', '+MgrFName AS Manager, 
    q.Center, 
    q.Queue AS 'Xferfrom', 
    e.anslogin, 
    e.origlogin, 
    t.Extension, 
    transferred, 
    disposition, 
    talktime, 
    dispsplit, 
    segment 
From CMS_ECH.dbo.CaliforniaECH e 

INNER JOIN Cal_RemReporting.dbo.TransferVDNs t on e.dialed_num = t.Extension 
INNER JOIN InfoQuest.dbo.IQ_Employee_Profiles_v3_AvayaId q on e.origlogin = q.AvayaID 
INNER JOIN Cal_RemReporting.dbo.udFiscalMonthTable f on e.SegStart_Date = f.Tdate 

Where SegStart_Date between getdate()-90 and getdate()-1 
    And q.Center not in ('Collections Center', 
         'Cable Store', 
         'Business Services Center', 
         'Escalations') 
    And SegStart_Date between RepToSup_StartDate and RepToSup_EndDate 
    And SegStart_Date between SupToMgr_StartDate and SupToMgr_EndDate 
    And SegStart_Date between Avaya_StartDate and Avaya_EndDate 
    And SegStart_Date between RepQueue_StartDate and RepQueue_EndDate 
    AND (e.transferred like '1' 
    OR e.disposition like '4') order by segstart 
) AS ANDREWSTABLE 

--Left Join CMS_ECH.dbo.hsplit hsplit on hsplit.starttime = ANDREWSTABLE.Interval and hsplit.row_date = ANDREWSTABLE.SegStart_Date and ANDREWSTABLE.dispsplit = hsplit.split

来源

2010-07-17 CodingIsAwesome