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嵌套視圖會降低性能，尋找提高性能的方法

2016-07-15 53 views
0

我正在使用SQl服務器，並且我創建了一個視圖，該視圖是從另一個視圖調用數據並且性能非常慢。有沒有提高性能的方法？嵌套視圖會降低性能，尋找提高性能的方法

第一種觀點（這一觀點被用來連接表，並創建標誌）這一觀點的

ALTER VIEW [dbo].[VW_MCCSR_FLAGS_MP] AS 

    SELECT TB2.*, 
    ----FLAGS FOR CSV (GF1) 
    CASE WHEN TB2.PAR_UL_01  IS NOT NULL AND TB2.ROW_ITEM = 'CSV (GF1)' THEN 1 ELSE 0 END AS CSV_GF1_PAR_UL_01_FLAG, 
    CASE WHEN TB2.NONPAR_UL_01 IS NOT NULL AND TB2.ROW_ITEM = 'CSV (GF1)' THEN 1 ELSE 0 END AS CSV_GF1_NONPAR_UL_01_FLAG, 
    CASE WHEN TB2.PAR_UL_19  IS NOT NULL AND TB2.ROW_ITEM = 'CSV (GF1)' THEN 1 ELSE 0 END AS CSV_GF1_PAR_UL_19_FLAG, 
    CASE WHEN TB2.NONPAR_UL_19 IS NOT NULL AND TB2.ROW_ITEM = 'CSV (GF1)' THEN 1 ELSE 0 END AS CSV_GF1_NONPAR_UL_19_FLAG, 
    CASE WHEN TB2.VUL_19  IS NOT NULL AND TB2.ROW_ITEM = 'CSV (GF1)' THEN 1 ELSE 0 END AS CSV_GF1_VUL_19_FLAG, 
    CASE WHEN TB2.UL_26   IS NOT NULL AND TB2.ROW_ITEM = 'CSV (GF1)' THEN 1 ELSE 0 END AS CSV_GF1_UL_26_FLAG, 
    CASE WHEN TB2.UL_67   IS NOT NULL AND TB2.ROW_ITEM = 'CSV (GF1)' THEN 1 ELSE 0 END AS CSV_GF1_UL_67_FLAG, 
    CASE WHEN TB2.UL_89   IS NOT NULL AND TB2.ROW_ITEM = 'CSV (GF1)' THEN 1 ELSE 0 END AS CSV_GF1_UL_89_FLAG, 
    CASE WHEN TB2.UL_94   IS NOT NULL AND TB2.ROW_ITEM = 'CSV (GF1)' THEN 1 ELSE 0 END AS CSV_GF1_UL_94_FLAG, 
    CASE WHEN TB2.VUL_94  IS NOT NULL AND TB2.ROW_ITEM = 'CSV (GF1)' THEN 1 ELSE 0 END AS CSV_GF1_VUL_94_FLAG, 
    CASE WHEN TB2.UL_102  IS NOT NULL AND TB2.ROW_ITEM = 'CSV (GF1)' THEN 1 ELSE 0 END AS CSV_GF1_UL_102_FLAG 

    FROM 

    (
    SELECT DISTINCT 'CSV' AS REPORT_NAME, 'CSV (GF1)' AS ROW_ITEM, 
    CASE WHEN TB1.GL_REINSURANCE_CLASS_CODE IS NULL AND TB1.GL_Legal_ID_BK = 1  AND TB1.US_SOE_Group_Code LIKE 'UL' AND TB1.Par_Code = 4 
     THEN SUM(TB1.Cash_Surrender_Value_Amt) END AS PAR_UL_01, 

    CASE WHEN TB1.GL_REINSURANCE_CLASS_CODE IS NULL AND TB1.GL_Legal_ID_BK = 1  AND TB1.US_SOE_Group_Code LIKE 'UL' AND TB1.Par_Code = 2 
     THEN SUM(TB1.Cash_Surrender_Value_Amt) END AS NONPAR_UL_01, 

    CASE WHEN TB1.GL_REINSURANCE_CLASS_CODE IS NULL AND TB1.GL_Legal_ID_BK = 19  AND TB1.US_SOE_Group_Code LIKE 'UL' AND TB1.Par_Code = 4 
     THEN SUM(TB1.Cash_Surrender_Value_Amt) END AS PAR_UL_19, 

    CASE WHEN TB1.GL_REINSURANCE_CLASS_CODE IS NULL AND TB1.GL_Legal_ID_BK = 19  AND TB1.US_SOE_Group_Code LIKE 'UL' AND TB1.Par_Code = 2 
     THEN SUM(TB1.Cash_Surrender_Value_Amt) END AS NONPAR_UL_19, 

    CASE WHEN TB1.GL_REINSURANCE_CLASS_CODE IS NULL AND TB1.GL_Legal_ID_BK = 19  AND TB1.US_SOE_Group_Code LIKE 'VUL' AND TB1.Par_Code = 2 
     THEN (SUM(TB1.Cash_Surrender_Value_Amt) - SUM(TB1.SEPERATE_ACCOUNT_VALUE)) END AS VUL_19, 

    CASE WHEN TB1.GL_REINSURANCE_CLASS_CODE IS NULL AND TB1.GL_Legal_ID_BK = 26  AND TB1.US_SOE_Group_Code LIKE 'UL' AND TB1.Par_Code = 2 
     THEN 0 END AS UL_26, 

    CASE WHEN TB1.GL_REINSURANCE_CLASS_CODE IS NULL AND TB1.GL_Legal_ID_BK = 94  AND TB1.US_SOE_Group_Code LIKE 'UL' AND TB1.Par_Code = 2 
     THEN (SUM(TB1.Cash_Surrender_Value_Amt)/0.09) END AS UL_67, 

    CASE WHEN TB1.GL_REINSURANCE_CLASS_CODE IS NULL AND TB1.GL_Legal_ID_BK = 89  AND TB1.US_SOE_Group_Code LIKE 'UL' AND TB1.Par_Code = 2 
     THEN SUM(TB1.Cash_Surrender_Value_Amt) END AS UL_89, 

    CASE WHEN TB1.GL_REINSURANCE_CLASS_CODE IS NULL AND TB1.GL_Legal_ID_BK = 94  AND TB1.US_SOE_Group_Code LIKE 'UL' AND TB1.Par_Code = 2 
     THEN SUM(TB1.Cash_Surrender_Value_Amt) END AS UL_94, 

    CASE WHEN TB1.GL_REINSURANCE_CLASS_CODE IS NULL AND TB1.GL_Legal_ID_BK = 94  AND TB1.US_SOE_Group_Code LIKE 'VUL' AND TB1.Par_Code = 2 
     THEN (SUM(TB1.Cash_Surrender_Value_Amt) - SUM(TB1.SEPERATE_ACCOUNT_VALUE)) END AS VUL_94, 

    CASE WHEN TB1.GL_REINSURANCE_CLASS_CODE IS NULL AND TB1.GL_Legal_ID_BK = 102 AND TB1.US_SOE_Group_Code LIKE 'UL' AND TB1.Par_Code = 2 
     THEN SUM(TB1.Cash_Surrender_Value_Amt) END AS UL_102 

    FROM 
    (SELECT distinct PF.POLICY_SID, PF.Cash_Surrender_Value_Amt ,CAST(PD.GL_Legal_ID_BK AS INT) AS GL_Legal_ID_BK,PD.US_SOE_Group_Code , CAST(PD.Par_Code AS INT) AS Par_Code 
    ,CAST(CD.GL_REINSURANCE_CLASS_CODE AS INT) AS GL_REINSURANCE_CLASS_CODE 
    , TBL1.FUND_BALANCE_AMT AS SEPERATE_ACCOUNT_VALUE 

    FROM POLICY_FACT PF 
    INNER JOIN Policy_DIM PD ON PF.Policy_SID = PD.Policy_SID 
    LEFT OUTER JOIN (SELECT DISTINCT crf.policy_sid , crf.coverage_sid FROM dbo.Coverage_rider_fact crf 
        WHERE CRF.Reporting_period_sid = (SELECT b.DATE_SID 
                 FROM 
                 [VSTPODS_US].[dbo].[REF_EXTRACT_MONTH] A 
                 INNER JOIN 
                  [dbo].date_dim b 
                 ON 
                  SUBSTRING(CAST(b.date_sid AS VARCHAR(8)),1,6) = A.EXTRACT_MONTH 
                  WHERE A.CURR_IND=1 AND B.Last_Day_of_the_Month_Ind = 1) 
                 ) CURF 
        ON PD.Policy_SID = CURF.POLICY_SID 

    LEFT OUTER JOIN COVERAGE_DIM CD ON CURF.Coverage_SID = CD.Coverage_SID 
    LEFT OUTER JOIN (SELECT FF.policy_sid, FF.FUND_BALANCE_AMT,FD.Fund_Account_Type_Code FROM 
        dbo.Fund_Account_Fact FF 
        INNER JOIN dbo.Fund_Account_dim FD ON FF.Fund_Account_sid = FD.Fund_Account_sid 
        WHERE FD.Fund_Account_Type_Code = 'S' AND 
        FF.Reporting_Period_SID = (SELECT b.DATE_SID 
                 FROM 
                 [VSTPODS_US].[dbo].[REF_EXTRACT_MONTH] A 
                 INNER JOIN 
                  [dbo].date_dim b 
                 ON 
                  SUBSTRING(CAST(b.date_sid AS VARCHAR(8)),1,6) = A.EXTRACT_MONTH 
                  WHERE A.CURR_IND=1 AND B.Last_Day_of_the_Month_Ind = 1) 
        ) TBL1 ON TBL1.Policy_sid = PF.Policy_SID 

     WHERE PF.Reporting_Period_SID = (SELECT b.DATE_SID 
                 FROM 
                 [VSTPODS_US].[dbo].[REF_EXTRACT_MONTH] A 
                 INNER JOIN 
                  [dbo].date_dim b 
                 ON 
                  SUBSTRING(CAST(b.date_sid AS VARCHAR(8)),1,6) = A.EXTRACT_MONTH 
                  WHERE A.CURR_IND=1 AND B.Last_Day_of_the_Month_Ind = 1)) AS TB1 
    GROUP BY TB1.GL_REINSURANCE_CLASS_CODE,TB1.GL_Legal_ID_BK,TB1.US_SOE_Group_Code, TB1.Par_Code) TB2

輸出是這樣enter image description here

，並調用視圖的腳本是

ALTER VIEW [dbo].[VW_MCCSR_USNT_OUTPUT_MP] AS 
    SELECT DISTINCT V1.REPORT_NAME, V1.ROW_ITEM, 
    (SELECT PAR_UL_01 FROM VW_MCCSR_FLAGS_MP WHERE CSV_GF1_PAR_UL_01_FLAG = 1)  AS PAR_UL_01, 
    (SELECT NONPAR_UL_01 FROM VW_MCCSR_FLAGS_MP WHERE CSV_GF1_NONPAR_UL_01_FLAG = 1) AS NONPAR_UL_01, 
    (SELECT PAR_UL_19 FROM dbo.VW_MCCSR_FLAGS_MP WHERE CSV_GF1_PAR_UL_19_FLAG IS NOT NULL ) AS PAR_UL_19, 
    (SELECT NONPAR_UL_19 FROM VW_MCCSR_FLAGS_MP WHERE CSV_GF1_NONPAR_UL_19_FLAG = 1) AS NONPAR_UL_19, 
    (SELECT VUL_19 FROM VW_MCCSR_FLAGS_MP WHERE CSV_GF1_VUL_19_FLAG = 1)    AS VUL_19, 
    (SELECT UL_26 FROM VW_MCCSR_FLAGS_MP WHERE CSV_GF1_UL_26_FLAG = 1 )    AS UL_26, 
    (SELECT UL_67 FROM VW_MCCSR_FLAGS_MP WHERE CSV_GF1_UL_67_FLAG = 1 )    AS UL_67, 
    (SELECT UL_89 FROM VW_MCCSR_FLAGS_MP WHERE CSV_GF1_UL_89_FLAG = 1 )    AS UL_89, 
    (SELECT UL_94 FROM VW_MCCSR_FLAGS_MP WHERE CSV_GF1_UL_94_FLAG = 1 )    AS UL_94, 
    (SELECT VUL_94 FROM VW_MCCSR_FLAGS_MP WHERE CSV_GF1_VUL_94_FLAG = 1)   AS VUL_94 , 
    (SELECT UL_102 FROM VW_MCCSR_FLAGS_MP WHERE CSV_GF1_UL_102_FLAG = 1)   AS UL_102 

    FROM 
    VW_MCCSR_FLAGS_MP V1 

    WHERE V1.ROW_ITEM = 'CSV (GF1)'

來源

2016-07-15 mb1987

+1

由於你的'（選擇PAR_UL_01'等字段沒有鏈接到視圖中的實際行，你不能使用max（）+ case來獲取值，而不是運行select來使相同視圖12次？ –

+0

你應該包括實際執行計劃。基於此，您可以看到哪些部分可以改進（通過索引，更改sql等）。 – Igor

+2

簡單。擺脫嵌套視圖。這是混淆優化器的一種可靠的方法。這似乎是一個合乎邏輯的想法，但嵌套視圖對於性能來說是很可怕的。除此之外，你一遍又一遍地重複同一個嵌套視圖，並且你有一個性能漏洞的配方。格蘭特在這裏介紹了一些細節。 https://www.simple-talk.com/sql/performance/the-seven-sins-against-tsql-performance/向下滾動大約一半的嵌套視圖部分。 –

回答

0

不是正面的，而是看起來像這樣的東西

SELECT distinct PF.POLICY_SID, PF.Cash_Surrender_Value_Amt 
    , CAST(PD.GL_Legal_ID_BK AS INT) AS GL_Legal_ID_BK,PD.US_SOE_Group_Code 
    , CAST(PD.Par_Code AS INT) AS Par_Code 
    , CAST(CD.GL_REINSURANCE_CLASS_CODE AS INT) AS GL_REINSURANCE_CLASS_CODE 
    , TBL1.FUND_BALANCE_AMT AS SEPERATE_ACCOUNT_VALUE 
FROM POLICY_FACT PF 
INNER JOIN Policy_DIM PD 
     ON PF.Policy_SID = PD.Policy_SID 
INNER JOIN [VSTPODS_US].[dbo].[REF_EXTRACT_MONTH] A 
     on b.DATE_SID = PF.Policy_SID 
INNER JOIN [dbo].date_dim b 
     ON SUBSTRING(CAST(b.date_sid AS VARCHAR(8)),1,6) = A.EXTRACT_MONTH 
     AND A.CURR_IND=1 AND B.Last_Day_of_the_Month_Ind = 1 
LEFT OUTER JOIN dbo.Coverage_rider_fact crf 
     ON PD.Policy_SID = CURF.POLICY_SID 
.....

來源

2016-07-15 18:27:15 Paparazzi

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