子查詢中的CTE

-1

我有一個場景來顯示來自2個表合併的數據。第一張表名爲'DayTable'由每日計劃和實際組成。名爲「MonthTable」的第二張表包含每月計劃和實際。我需要顯示最近6個月的數據和當前的每日數據。所以我寫了下面我喜歡的查詢的預期產出子查詢中的CTE

Declare @startdate date = CONVERT(DATE, DATEADD(dd, -DAY(DATEADD(MONTH, 0, GETDATE())) + 1, DATEADD(MONTH, 0, GETDATE()))) 
Declare @endDate date = DATEADD(DAY, -DAY(DATEADD(MONTH, 1, GETDATE())), DATEADD(MONTH, 1, GETDATE())) 

CREATE TABLE #TEMP 
(
PlanDate NVARCHAR(100), 
[PastTrend - Plan] INT, 
[PastTrend - Actual] INT, 
[Current - Plan] INT, 
[Current - Actual] INT, 
) 

;With cte 
as 
(
    Select @startdate sDate 
    Union All 
    Select DATEADD(day,1,sDate) From cte where DATEADD(day,1,sDate) <= @endDate 
) 
INSERT INTO #TEMP 
SELECT 
REPLACE(CONVERT(CHAR(6), A.sDate, 106),' ',' - ') PlanDate 
,NULL AS [PastTrend - Plan] 
,NULL AS [PastTrend - Actual] 
,SUM(B.PlanQuantity) AS [Current - Plan] 
,SUM(B.Actual) AS [Current - Actual] 
FROM cte A 
LEFT OUTER JOIN DayTable B 
ON A.sDate = CONVERT(DATE,B.PlanDate) 
GROUP BY A.sDate 
--ORDER BY A.sDate 


SELECT 
* 

FROM 
(
SELECT 
CONVERT(CHAR(3), datename(month,PlanMonth)) + ' ' + RIGHT(CONVERT(VARCHAR(4), YEAR(PlanMonth)), 2) AS PlanDate 
,SUM(PlanQuantity) AS [PastTrend - Plan] 
,SUM(Actual) AS [PastTrend - Actual] 
,NULL AS [Current - Plan] 
,NULL AS [Current - Actual] 
FROM 
MonthTable 
WHERE CONVERT(DATE, PlanMonth) >= CONVERT(DATE, DATEADD(dd, -DAY(DATEADD(MONTH, 0, GETDATE())) + 1, DATEADD(MONTH, -6, GETDATE()))) 
group by PlanMonth 


UNION ALL 

SELECT 
PlanDate 
,[PastTrend - Plan] 
,[PastTrend - Actual] 
,[Current - Plan] 
,[Current - Actual] 
FROM 
#TEMP 

) T1 


DROP TABLE #TEMP

我的輸出是一樣

Output Image

現在我稀化，以避免臨時表的概念，因爲如果出現任何故障創建臨時表之後不會下降。所以重寫下面的查詢

Declare @startdate date = CONVERT(DATE, DATEADD(dd, -DAY(DATEADD(MONTH, 0, GETDATE())) + 1, DATEADD(MONTH, 0, GETDATE()))) 
Declare @endDate date = DATEADD(DAY, -DAY(DATEADD(MONTH, 1, GETDATE())), DATEADD(MONTH, 1, GETDATE())) 

;With cte 
as 
(
    Select @startdate sDate 
    Union All 
    Select DATEADD(day,1,sDate) From cte where DATEADD(day,1,sDate) <= @endDate 
) 
SELECT 
A.sDate AS OriginalDate 
,REPLACE(CONVERT(CHAR(6), A.sDate, 106),' ',' - ') PlanDate 
,NULL AS [PastTrend - Plan] 
,NULL AS [PastTrend - Actual] 
,SUM(B.PlanQuantity) AS [Current - Plan] 
,SUM(B.Actual) AS [Current - Actual] 
FROM cte A 
LEFT OUTER JOIN DayTable B 
ON A.sDate = CONVERT(DATE,B.PlanDate) 
GROUP BY A.sDate 

UNION ALL 

SELECT 
PlanMonth AS OriginalDate 
,CONVERT(CHAR(3), datename(month,PlanMonth)) + ' ' + RIGHT(CONVERT(VARCHAR(4), YEAR(PlanMonth)), 2) AS PlanDate 
,SUM(PlanQuantity) AS [PastTrend - Plan] 
,SUM(Actual) AS [PastTrend - Actual] 
,NULL AS [Current - Plan] 
,NULL AS [Current - Actual] 
FROM 
MonthTable 
WHERE CONVERT(DATE, PlanMonth) >= CONVERT(DATE, DATEADD(dd, -DAY(DATEADD(MONTH, 0, GETDATE())) + 1, DATEADD(MONTH, -6, GETDATE()))) 
group by PlanMonth 

ORDER BY OriginalDate

但在這裏我有問題。在輸出我不需要OriginalDate。如何避免這一點。爲此，我可以將聯合輸出包裝爲一個選擇查詢，但是如何在cte中得到錯誤。請指導我。還建議哪種方法最好一個

來源

2014-04-23 Akhil

爲什麼不只是在臨時表中包含「IF EXISTS .... DROP」？你也可以考慮一個'TRY..CATCH'邏輯來刪除臨時表，以防止失敗 – Raj

是一個好主意。但我試圖避免臨時表。我不知道哪種方法好。我認爲直接的方法很簡單，很好。也是這樣，我有其他程序也使用溫度。所以想避免它。就這樣。如果臨時表是更好的方法，我可以這樣做 – Akhil

我完成了查詢。事實上，我只是將查詢包裝爲外部的cte。 Cte必須是查詢中的頂部。最後的查詢是

Declare @startdate date = CONVERT(DATE, DATEADD(dd, -DAY(DATEADD(MONTH, 0, GETDATE())) + 1, DATEADD(MONTH, 0, GETDATE()))) 
    Declare @endDate date = DATEADD(DAY, -DAY(DATEADD(MONTH, 1, GETDATE())), DATEADD(MONTH, 1, GETDATE())) 



;With cte 
    as 
    (
     Select @startdate sDate 
     Union All 
     Select DATEADD(day,1,sDate) From cte where DATEADD(day,1,sDate) <= @endDate 
    ) 
    SELECT 
    T1.PlanDate 
    ,T1.[PastTrend - Plan] 
    ,T1.[PastTrend - Actual] 
    ,T1.[Current - Plan] 
    ,T1.[Current - Actual] 
    FROM 
    (
    SELECT 
    A.sDate AS OriginalDate 
    ,REPLACE(CONVERT(CHAR(6), A.sDate, 106),' ',' - ') PlanDate 
    ,NULL AS [PastTrend - Plan] 
    ,NULL AS [PastTrend - Actual] 
    ,SUM(B.PlanQuantity) AS [Current - Plan] 
    ,SUM(B.Actual) AS [Current - Actual] 
    FROM cte A 
    LEFT OUTER JOIN DayTable B 
    ON A.sDate = CONVERT(DATE,B.PlanDate) 
    GROUP BY A.sDate 

    UNION ALL 

    SELECT 
    PlanMonth AS OriginalDate 
    ,CONVERT(CHAR(3), datename(month,PlanMonth)) + ' ' + RIGHT(CONVERT(VARCHAR(4), YEAR(PlanMonth)), 2) AS PlanDate 
    ,SUM(PlanQuantity) AS [PastTrend - Plan] 
    ,SUM(Actual) AS [PastTrend - Actual] 
    ,NULL AS [Current - Plan] 
    ,NULL AS [Current - Actual] 
    FROM 
    MonthTable 
    WHERE CONVERT(DATE, PlanMonth) >= CONVERT(DATE, DATEADD(dd, -DAY(DATEADD(MONTH, 0, GETDATE())) + 1, DATEADD(MONTH, -6, GETDATE()))) 
    group by PlanMonth 
    ) T1 
    ORDER BY T1.OriginalDate

但我需要知道性能。當我執行此查詢與實際執行計劃查詢成本（相對於批次）：100％當我執行第一個方法使用溫度查詢成本是90％。任何人都可以爲此指導

來源

2014-04-23 05:25:43 Akhil

子查詢中的CTE

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