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尽量避免SQL Server查询中的联合

union sql-server sql
  •  -4
  • Samuel Rayanne  · 技术社区  · 7 年前

    我有一个为呼叫中心收集不同指标的查询: 

        SELECT      CONCAT (DEPARTMENT_DESC, 'Week', datepart(wk, ROW_DATE)) As Dept_Date,
            datepart(wk, ROW_DATE) as weeknum,
            DEPARTMENT_DESC AS DEPT,
            SUM([CALLS_OFFERED_ACTUALS]) As LCW_Calls_Offered,
            MAX(LCW) AS LCW,
            (SUM(ANSTIME) / SUM(CALLS_ANSWERED_ACTUALS)) AS ASA,
            SUM(HANDLED_TIME) / SUM(CALLS_ANSWERED_ACTUALS) AS AHT,
            SUM(HANDLED_TIME) as handletime,
            SUM(CALLS_OFFERED_FCST) AS Call_Target,
            SUM(CALLS_ANSWERED_ACTUALS) as call_answered,
            CAST(1.000*(SUM(TRANSFERS)+SUM(CONFERENCE)) / SUM(CALLS_ANSWERED_ACTUALS) AS DECIMAL(19,3)) AS Transf_Rate,
            CAST(1.000*(SUM(CALLS_ABD_ACTUALS)) / SUM([CALLS_OFFERED_ACTUALS]) AS DECIMAL(19,3)) AS Abandon_Rate,
            1-CAST(1.000*(SUM(LCW60)) / SUM(INT_CNT) AS DECIMAL(19,3)) AS LCW_INT,
            CAST(1.000*(SUM(ONLINETIME)-SUM(AVAILTIME)-SUM(ALARMTIME))/SUM(ONLINETIME)  AS DECIMAL(19,3)) AS Occupancy,
            CAST(1.000*(SUM(PRODTIME)) / SUM(ATWORKTIME) AS DECIMAL(19,3)) AS Productivity,
            CAST(1.000*(SUM(AVAILTIME)) / SUM(ATWORKTIME) AS DECIMAL(19,3)) AS Availab,
            CAST(1.000*(SUM(OVERTIME)) / SUM(WORKFORCETIME) AS DECIMAL(19,3)) AS Overtime,
            CAST(1.000*(SUM(UNPROD_TIME_UNPLANNED)) / SUM(WORKFORCETIME) AS DECIMAL(19,3)) AS Unplanned_Shrink,
            CAST(1.000*(SUM(UNPROD_TIME_PLANNED)) / SUM(WORKFORCETIME) AS DECIMAL(19,3)) AS Planned_Shrink,
            CAST(1.000*(SUM(CALLS_ANSWERED_INT1)+SUM(CALLS_ANSWERED_INT2)) / SUM(CALLS_OFFERED_ACTUALS) AS DECIMAL(19,3)) AS SL_Within_20,
            CAST(1.000*(SUM(CALLS_ANSWERED_INT1)+SUM(CALLS_ANSWERED_INT2)+SUM(CALLS_ANSWERED_INT3)+SUM(CALLS_ANSWERED_INT4)+SUM(CALLS_ANSWERED_INT5)+SUM(CALLS_ANSWERED_INT6)) / SUM(CALLS_OFFERED_ACTUALS) AS DECIMAL(19,3)) AS Calls_Within_60,
            1-CAST(1.000*(SUM(LCW300)) / SUM(INT_CNT) AS DECIMAL(19,3)) AS LCW_INT1,
            1-CAST(1.000*(SUM(LCW120)) / SUM(INT_CNT) AS DECIMAL(19,3)) AS LCW_INT2
      FROM [GEMDB].[dbo].[v_calls_LCW_Splitday]
  where datepart(wk, ROW_DATE) >= (datepart(wk, GETDATE()) - 6) AND datepart(year, ROW_DATE) = 2017
  GROUP BY datepart(wk, ROW_DATE), DEPARTMENT_DESC --((CALLS_ANSWERED_INT1 + CALLS_ANSWERED_INT2) / [CALLS_OFFERED_ACTUALS]) 
  ORDER BY datepart(wk, ROW_DATE

    )

    我们决定创建一个名为客户服务的新子部门,该部门由计费和;共同提供技术支持。

    我找到了一种方法,通过对另一个查询进行联合,该查询只选择用于计费的数据;技术支持。 

    /****** Script for SelectTopNRows command from SSMS  ******/


SELECT      CONCAT ('CS', 'Week', datepart(wk, ROW_DATE)) As Dept_Date,
            datepart(wk, ROW_DATE) as weeknum,
            CONCAT('CS','DEPT') AS DEPT,
            SUM([CALLS_OFFERED_ACTUALS]) As LCW_Calls_Offered,
            MAX(LCW) AS LCW,
            (SUM(ANSTIME) / SUM(CALLS_ANSWERED_ACTUALS)) AS ASA,
            SUM(HANDLED_TIME) / SUM(CALLS_ANSWERED_ACTUALS) AS AHT,
            SUM(HANDLED_TIME) as handletime,
            SUM(CALLS_OFFERED_FCST) AS Call_Target,
            SUM(CALLS_ANSWERED_ACTUALS) as call_answered,
            CAST(1.000*(SUM(TRANSFERS)+SUM(CONFERENCE)) / SUM(CALLS_ANSWERED_ACTUALS) AS DECIMAL(19,3)) AS Transf_Rate,
            CAST(1.000*(SUM(CALLS_ABD_ACTUALS)) / SUM([CALLS_OFFERED_ACTUALS]) AS DECIMAL(19,3)) AS Abandon_Rate,
            1-CAST(1.000*(SUM(LCW60)) / SUM(INT_CNT) AS DECIMAL(19,3)) AS LCW_INT,
            CAST(1.000*(SUM(ONLINETIME)-SUM(AVAILTIME)-SUM(ALARMTIME))/SUM(ONLINETIME)  AS DECIMAL(19,3)) AS Occupancy,
            CAST(1.000*(SUM(PRODTIME)) / SUM(ATWORKTIME) AS DECIMAL(19,3)) AS Productivity,
            CAST(1.000*(SUM(AVAILTIME)) / SUM(ATWORKTIME) AS DECIMAL(19,3)) AS Availab,
            CAST(1.000*(SUM(OVERTIME)) / SUM(WORKFORCETIME) AS DECIMAL(19,3)) AS Overtime,
            CAST(1.000*(SUM(UNPROD_TIME_UNPLANNED)) / SUM(WORKFORCETIME) AS DECIMAL(19,3)) AS Unplanned_Shrink,
            CAST(1.000*(SUM(UNPROD_TIME_PLANNED)) / SUM(WORKFORCETIME) AS DECIMAL(19,3)) AS Planned_Shrink,
            CAST(1.000*(SUM(CALLS_ANSWERED_INT1)+SUM(CALLS_ANSWERED_INT2)) / SUM(CALLS_OFFERED_ACTUALS) AS DECIMAL(19,3)) AS SL_Within_20,
            CAST(1.000*(SUM(CALLS_ANSWERED_INT1)+SUM(CALLS_ANSWERED_INT2)+SUM(CALLS_ANSWERED_INT3)+SUM(CALLS_ANSWERED_INT4)+SUM(CALLS_ANSWERED_INT5)+SUM(CALLS_ANSWERED_INT6)) / SUM(CALLS_OFFERED_ACTUALS) AS DECIMAL(19,3)) AS Calls_Within_60,
            1-CAST(1.000*(SUM(LCW300)) / SUM(INT_CNT) AS DECIMAL(19,3)) AS LCW_INT1,
            1-CAST(1.000*(SUM(LCW120)) / SUM(INT_CNT) AS DECIMAL(19,3)) AS LCW_INT2
        INTO #TEMP_CS   
    FROM [GEMDB].[dbo].[v_calls_LCW_Splitday]
  where datepart(wk, ROW_DATE) >= (datepart(wk, GETDATE()) - 6) AND datepart(year, ROW_DATE) = 2017
  AND DEPARTMENT_DESC IN ('BILLING', 'TechOps')
   GROUP BY datepart(wk, ROW_DATE) --((CALLS_ANSWERED_INT1 + CALLS_ANSWERED_INT2) / [CALLS_OFFERED_ACTUALS]) 
  ORDER BY datepart(wk, ROW_DATE)


  SELECT        CONCAT (DEPARTMENT_DESC, 'Week', datepart(wk, ROW_DATE)) As Dept_Date,
            datepart(wk, ROW_DATE) as weeknum,
            DEPARTMENT_DESC AS DEPT,
            SUM([CALLS_OFFERED_ACTUALS]) As LCW_Calls_Offered,
            MAX(LCW) AS LCW,
            (SUM(ANSTIME) / SUM(CALLS_ANSWERED_ACTUALS)) AS ASA,
            SUM(HANDLED_TIME) / SUM(CALLS_ANSWERED_ACTUALS) AS AHT,
            SUM(HANDLED_TIME) as handletime,
            SUM(CALLS_OFFERED_FCST) AS Call_Target,
            SUM(CALLS_ANSWERED_ACTUALS) as call_answered,
            CAST(1.000*(SUM(TRANSFERS)+SUM(CONFERENCE)) / SUM(CALLS_ANSWERED_ACTUALS) AS DECIMAL(19,3)) AS Transf_Rate,
            CAST(1.000*(SUM(CALLS_ABD_ACTUALS)) / SUM([CALLS_OFFERED_ACTUALS]) AS DECIMAL(19,3)) AS Abandon_Rate,
            1-CAST(1.000*(SUM(LCW60)) / SUM(INT_CNT) AS DECIMAL(19,3)) AS LCW_INT,
            CAST(1.000*(SUM(ONLINETIME)-SUM(AVAILTIME)-SUM(ALARMTIME))/SUM(ONLINETIME)  AS DECIMAL(19,3)) AS Occupancy,
            CAST(1.000*(SUM(PRODTIME)) / SUM(ATWORKTIME) AS DECIMAL(19,3)) AS Productivity,
            CAST(1.000*(SUM(AVAILTIME)) / SUM(ATWORKTIME) AS DECIMAL(19,3)) AS Availab,
            CAST(1.000*(SUM(OVERTIME)) / SUM(WORKFORCETIME) AS DECIMAL(19,3)) AS Overtime,
            CAST(1.000*(SUM(UNPROD_TIME_UNPLANNED)) / SUM(WORKFORCETIME) AS DECIMAL(19,3)) AS Unplanned_Shrink,
            CAST(1.000*(SUM(UNPROD_TIME_PLANNED)) / SUM(WORKFORCETIME) AS DECIMAL(19,3)) AS Planned_Shrink,
            CAST(1.000*(SUM(CALLS_ANSWERED_INT1)+SUM(CALLS_ANSWERED_INT2)) / SUM(CALLS_OFFERED_ACTUALS) AS DECIMAL(19,3)) AS SL_Within_20,
            CAST(1.000*(SUM(CALLS_ANSWERED_INT1)+SUM(CALLS_ANSWERED_INT2)+SUM(CALLS_ANSWERED_INT3)+SUM(CALLS_ANSWERED_INT4)+SUM(CALLS_ANSWERED_INT5)+SUM(CALLS_ANSWERED_INT6)) / SUM(CALLS_OFFERED_ACTUALS) AS DECIMAL(19,3)) AS Calls_Within_60,
            1-CAST(1.000*(SUM(LCW300)) / SUM(INT_CNT) AS DECIMAL(19,3)) AS LCW_INT1,
            1-CAST(1.000*(SUM(LCW120)) / SUM(INT_CNT) AS DECIMAL(19,3)) AS LCW_INT2
            INTO #TEMP_ALL
   FROM [GEMDB].[dbo].[v_calls_LCW_Splitday]
  where datepart(wk, ROW_DATE) >= (datepart(wk, GETDATE()) - 6) AND datepart(year, ROW_DATE) = 2017
   GROUP BY datepart(wk, ROW_DATE), DEPARTMENT_DESC --((CALLS_ANSWERED_INT1 + CALLS_ANSWERED_INT2) / [CALLS_OFFERED_ACTUALS]) 
     ORDER BY datepart(wk, ROW_DATE)


  SELECT *
  FROM #TEMP_ALL
  UNION
  SELECT *
  FROM #TEMP_CS

  DROP TABLE #TEMP_ALL
  DROP TABLE #TEMP_CS

    有没有更有效的方法来实现这一点?我们不能等待3分钟以上才能完成此查询。

    谢谢

    1 回复  |  直到 7 年前
        1
  •  2
  •   xQbert    7 年前
    • 不知道你为什么需要临时表格
    • 不确定为什么需要使用union vs union all
    • case when DEPARTMENT_DESC in IN ('BILLING', 'TechOps') then 'Customer Service' else DEPARTMENT_DESC end .

    保留union,但使用union all并避免临时表。 

    /****** Script for SelectTopNRows command from SSMS  ******/
SELECT CONCAT ('CS', 'Week', datepart(wk, ROW_DATE)) As Dept_Date
     , datepart(wk, ROW_DATE) as weeknum
     , CONCAT('CS','DEPT') AS DEPT
     , SUM([CALLS_OFFERED_ACTUALS]) As LCW_Calls_Offered
     , MAX(LCW) AS LCW
     , SUM(ANSTIME) / SUM(CALLS_ANSWERED_ACTUALS) AS ASA
     , SUM(HANDLED_TIME) / SUM(CALLS_ANSWERED_ACTUALS) AS AHT
     , SUM(HANDLED_TIME) as handletime
     , SUM(CALLS_OFFERED_FCST) AS Call_Target
     , SUM(CALLS_ANSWERED_ACTUALS) as call_answered
     , CAST(1.000*(SUM(TRANSFERS)+SUM(CONFERENCE)) / SUM(CALLS_ANSWERED_ACTUALS) AS DECIMAL(19,3)) AS Transf_Rate
     , CAST(1.000*(SUM(CALLS_ABD_ACTUALS)) / SUM([CALLS_OFFERED_ACTUALS]) AS DECIMAL(19,3)) AS Abandon_Rate
     , 1-CAST(1.000*(SUM(LCW60)) / SUM(INT_CNT) AS DECIMAL(19,3)) AS LCW_INT
     , CAST(1.000*(SUM(ONLINETIME)-SUM(AVAILTIME)-
     , SUM(ALARMTIME))/SUM(ONLINETIME)  AS DECIMAL(19,3)) AS Occupancy
     , CAST(1.000*(SUM(PRODTIME)) / SUM(ATWORKTIME) AS DECIMAL(19,3)) AS Productivity
     , CAST(1.000*(SUM(AVAILTIME)) / SUM(ATWORKTIME) AS DECIMAL(19,3)) AS Availab
     , CAST(1.000*(SUM(OVERTIME)) / SUM(WORKFORCETIME) AS DECIMAL(19,3)) AS Overtime
     , CAST(1.000*(SUM(UNPROD_TIME_UNPLANNED)) / SUM(WORKFORCETIME) AS DECIMAL(19,3)) AS Unplanned_Shrink
     , CAST(1.000*(SUM(UNPROD_TIME_PLANNED)) / SUM(WORKFORCETIME) AS DECIMAL(19,3)) AS Planned_Shrink
     , CAST(1.000*(SUM(CALLS_ANSWERED_INT1)+SUM(CALLS_ANSWERED_INT2)) / SUM(CALLS_OFFERED_ACTUALS) AS DECIMAL(19,3)) AS SL_Within_20
     , CAST(1.000*(SUM(CALLS_ANSWERED_INT1)+SUM(CALLS_ANSWERED_INT2)+SUM(CALLS_ANSWERED_INT3)+SUM(CALLS_ANSWERED_INT4)+SUM(CALLS_ANSWERED_INT5)+SUM(CALLS_ANSWERED_INT6)) / SUM(CALLS_OFFERED_ACTUALS) AS DECIMAL(19,3)) AS Calls_Within_60
     , 1-CAST(1.000*(SUM(LCW300)) / SUM(INT_CNT) AS DECIMAL(19,3)) AS LCW_INT1
     , 1-CAST(1.000*(SUM(LCW120)) / SUM(INT_CNT) AS DECIMAL(19,3)) AS LCW_INT2
FROM [GEMDB].[dbo].[v_calls_LCW_Splitday]
WHERE  datepart(wk, ROW_DATE) >= (datepart(wk, GETDATE()) - 6) 
  AND datepart(year, ROW_DATE) = 2017
  AND DEPARTMENT_DESC IN ('BILLING', 'TechOps')
GROUP BY datepart(wk, ROW_DATE) --((CALLS_ANSWERED_INT1 + CALLS_ANSWERED_INT2) / [CALLS_OFFERED_ACTUALS]) 
ORDER BY datepart(wk, ROW_DATE)

UNION ALL

SELECT CONCAT (DEPARTMENT_DESC, 'Week', datepart(wk, ROW_DATE)) As Dept_Date
     , datepart(wk, ROW_DATE) as weeknum
     , DEPARTMENT_DESC AS DEPT
     , SUM([CALLS_OFFERED_ACTUALS]) As LCW_Calls_Offered
     , MAX(LCW) AS LCW
     , SUM(ANSTIME) / SUM(CALLS_ANSWERED_ACTUALS) AS ASA
     , SUM(HANDLED_TIME) / SUM(CALLS_ANSWERED_ACTUALS) AS AHT
     , SUM(HANDLED_TIME) as handletime
     , SUM(CALLS_OFFERED_FCST) AS Call_Target
     , SUM(CALLS_ANSWERED_ACTUALS) as call_answered
     , CAST(1.000*(SUM(TRANSFERS)+SUM(CONFERENCE)) / SUM(CALLS_ANSWERED_ACTUALS) AS DECIMAL(19,3)) AS Transf_Rate
     , CAST(1.000*(SUM(CALLS_ABD_ACTUALS)) / SUM([CALLS_OFFERED_ACTUALS]) AS DECIMAL(19,3)) AS Abandon_Rate
     , 1-CAST(1.000*(SUM(LCW60)) / SUM(INT_CNT) AS DECIMAL(19,3)) AS LCW_INT
     , CAST(1.000*(SUM(ONLINETIME)-SUM(AVAILTIME)-SUM(ALARMTIME))/SUM(ONLINETIME)  AS DECIMAL(19,3)) AS Occupancy
     , CAST(1.000*(SUM(PRODTIME)) / SUM(ATWORKTIME) AS DECIMAL(19,3)) AS Productivity
     , CAST(1.000*(SUM(AVAILTIME)) / SUM(ATWORKTIME) AS DECIMAL(19,3)) AS Availab
     , CAST(1.000*(SUM(OVERTIME)) / SUM(WORKFORCETIME) AS DECIMAL(19,3)) AS Overtime
     , CAST(1.000*(SUM(UNPROD_TIME_UNPLANNED)) / SUM(WORKFORCETIME) AS DECIMAL(19,3)) AS Unplanned_Shrink
     , CAST(1.000*(SUM(UNPROD_TIME_PLANNED)) / SUM(WORKFORCETIME) AS DECIMAL(19,3)) AS Planned_Shrink
     , CAST(1.000*(SUM(CALLS_ANSWERED_INT1)+SUM(CALLS_ANSWERED_INT2)) / SUM(CALLS_OFFERED_ACTUALS) AS DECIMAL(19,3)) AS SL_Within_20
     , CAST(1.000*(SUM(CALLS_ANSWERED_INT1)+SUM(CALLS_ANSWERED_INT2)+SUM(CALLS_ANSWERED_INT3)+SUM(CALLS_ANSWERED_INT4)+SUM(CALLS_ANSWERED_INT5)+SUM(CALLS_ANSWERED_INT6)) / SUM(CALLS_OFFERED_ACTUALS) AS DECIMAL(19,3)) AS Calls_Within_60
     , 1-CAST(1.000*(SUM(LCW300)) / SUM(INT_CNT) AS DECIMAL(19,3)) AS LCW_INT1
     , 1-CAST(1.000*(SUM(LCW120)) / SUM(INT_CNT) AS DECIMAL(19,3)) AS LCW_INT2

FROM [GEMDB].[dbo].[v_calls_LCW_Splitday]
WHERE datepart(wk, ROW_DATE) >= (datepart(wk, GETDATE()) - 6) 
  AND datepart(year, ROW_DATE) = 2017
GROUP BY datepart(wk, ROW_DATE)
       , DEPARTMENT_DESC --((CALLS_ANSWERED_INT1 + CALLS_ANSWERED_INT2) / [CALLS_OFFERED_ACTUALS]) 
ORDER BY datepart(wk, ROW_DATE)


    case when DEPARTMENT_DESC in IN ('BILLING', 'TechOps')  
                then 'Customer Service' 
                else DEPARTMENT_DESC end

    所以我接受了你的第一个问题,就这么做了。 

    SELECT CONCAT(case when DEPARTMENT_DESC in IN ('BILLING', 'TechOps')  
                   then 'Customer Service' 
                   else DEPARTMENT_DESC end
              , 'Week', datepart(wk, ROW_DATE)) As Dept_Date
     , datepart(wk, ROW_DATE) as weeknum
     , case when DEPARTMENT_DESC in IN ('BILLING', 'TechOps')  
            then 'Customer Service' 
            else DEPARTMENT_DESC end AS DEPT
     , SUM([CALLS_OFFERED_ACTUALS]) As LCW_Calls_Offered
     , MAX(LCW) AS LCW
     , SUM(ANSTIME) / SUM(CALLS_ANSWERED_ACTUALS) AS ASA
     , SUM(HANDLED_TIME) / SUM(CALLS_ANSWERED_ACTUALS) AS AHT
     , SUM(HANDLED_TIME) as handletime
     , SUM(CALLS_OFFERED_FCST) AS Call_Target
     , SUM(CALLS_ANSWERED_ACTUALS) as call_answered
     , CAST(1.000*(SUM(TRANSFERS)+SUM(CONFERENCE)) / SUM(CALLS_ANSWERED_ACTUALS) AS DECIMAL(19,3)) AS Transf_Rate
     , CAST(1.000*(SUM(CALLS_ABD_ACTUALS)) / SUM([CALLS_OFFERED_ACTUALS]) AS DECIMAL(19,3)) AS Abandon_Rate
     , 1-CAST(1.000*(SUM(LCW60)) / SUM(INT_CNT) AS DECIMAL(19,3)) AS LCW_INT
     , CAST(1.000*(SUM(ONLINETIME)-SUM(AVAILTIME)-SUM(ALARMTIME))/SUM(ONLINETIME)  AS DECIMAL(19,3)) AS Occupancy
     , CAST(1.000*(SUM(PRODTIME)) / SUM(ATWORKTIME) AS DECIMAL(19,3)) AS Productivity
     , CAST(1.000*(SUM(AVAILTIME)) / SUM(ATWORKTIME) AS DECIMAL(19,3)) AS Availab
     , CAST(1.000*(SUM(OVERTIME)) / SUM(WORKFORCETIME) AS DECIMAL(19,3)) AS Overtime
     , CAST(1.000*(SUM(UNPROD_TIME_UNPLANNED)) / SUM(WORKFORCETIME) AS DECIMAL(19,3)) AS Unplanned_Shrink
     , CAST(1.000*(SUM(UNPROD_TIME_PLANNED)) / SUM(WORKFORCETIME) AS DECIMAL(19,3)) AS Planned_Shrink
     , CAST(1.000*(SUM(CALLS_ANSWERED_INT1)+SUM(CALLS_ANSWERED_INT2)) / SUM(CALLS_OFFERED_ACTUALS) AS DECIMAL(19,3)) AS SL_Within_20
     , CAST(1.000*(SUM(CALLS_ANSWERED_INT1)+SUM(CALLS_ANSWERED_INT2)+SUM(CALLS_ANSWERED_INT3)+SUM(CALLS_ANSWERED_INT4)+SUM(CALLS_ANSWERED_INT5)+SUM(CALLS_ANSWERED_INT6)) / SUM(CALLS_OFFERED_ACTUALS) AS DECIMAL(19,3)) AS Calls_Within_60
     , 1-CAST(1.000*(SUM(LCW300)) / SUM(INT_CNT) AS DECIMAL(19,3)) AS LCW_INT1
     , 1-CAST(1.000*(SUM(LCW120)) / SUM(INT_CNT) AS DECIMAL(19,3)) AS LCW_INT2
FROM [GEMDB].[dbo].[v_calls_LCW_Splitday]
WHERE datepart(wk, ROW_DATE) >= (datepart(wk, GETDATE()) - 6) 
  AND datepart(year, ROW_DATE) = 2017
GROUP BY datepart(wk, ROW_DATE)
       , case when DEPARTMENT_DESC in IN ('BILLING', 'TechOps')  
              then 'Customer Service' 
              else DEPARTMENT_DESC end  --((CALLS_ANSWERED_INT1 + CALLS_ANSWERED_INT2) / [CALLS_OFFERED_ACTUALS]) 
ORDER BY datepart(wk, ROW_DATE
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