我的一个查询(它用于创建报告,因此它只包含：where’s,join’s和group by’s)在约20分钟后返回超时.预计执行计划向我显示：
此哈希匹配可能意味着我的查询的group by子句.但对我来说有趣的是Estimated Data Size~3TB,比我的数据库大10倍.经过调查,我认识到高度增加此数据传输的查询执行部分：
但由于预计执行计划,此嵌套循环对查询成本有任何影响.
此查询由Reporting Services生成并捕获(我删除了一些未使用的部分)：
SET DATEFIRST 7
SELECT
SUM([f_orders].[LORDEREDQTY_PU]) [QtyPU],
SUM((((((((([f_orders].[DTRANSFERPRICE] + [f_orders].[DICSBASICORDERFEE]) + [f_orders].[DICSFREIGHTCHARGE]) + [f_orders].[DICSINSURANCEFEE]) + [f_orders].[DICSPACKINGFEE]) + [f_orders].[DICSFREETXTFEE]) + [f_orders].[DICSLOGISTICSFEE]) + [f_orders].[DICSPACKAGEPACKINGFEE]) * [A_ExchangeRates].[USDRate])) [TPinclChargesinUSDBudgetexchangerate],
[f_orders].[LORDEREDQTY] [TotalQty],
[dbo_D_ORDERADDRESS].[Countrycode] [Countrycode],
[D_PRODUCT_NEW].[Framesize] [Framesize],
[f_orders].[SZCUSSHORTNAME] [Customershortname],
[f_orders].[SZCUSNO] [Customerno],
[D_PRODUCT_NEW].[Generationcode] [Generationcode],
[D_PU].[PU] [PU],
[D_BALIDINFO].[SRU] [SRU],
[D_WAREHOUSE].[Warehouse] [Warehouse],
[f_orders].[DATE_OrderBookedatSU] [OrderbookedatSU],
[f_orders].[DTCONFIRMEDDEL] [Confirmeddeliverydate],
[D_PRODUCT_NEW].[MotorsProductType] [MotorsProductType],
[f_orders].[SZORDERNO] [Orderno],
[f_orders].[IORDERLINENO] [Orderlineno],
[D_FRAMESIZE].[Framesize1] [Framesize1],
[D_PRODGROUP].[Productgroup] [Productgroup],
[D_PRODTYPE].[Producttype] [Producttype],
[f_orders].[SZPRODNO] [Productno],
[D_TYPEOFORDHAND].[Typeoforderhandling] [Typeoforderhandling],
CASE WHEN COALESCE(LEN([f_orders].[SZVARIANTCODE]), 0) = 0 THEN CAST([f_orders].[IVARIANTCODENO] AS VARCHAR(255)) ELSE [f_orders].[SZVARIANTCODE] END [Variantcodeno],
[f_orders].[IVARIANTIDX] [Variantindex],
[f_orders].[DATE_OrderBookedatSU] [OrderbookedatSU1],
[f_orders].[DATE_OrderBookedatSU] [OrderbookedatSU2]
FROM
[dbo].[f_orders] [f_orders]
LEFT OUTER JOIN (
SELECT
[dbo_D_ORDERADDRESS].[SZCOUNTRYCODE] [Countrycode],
[dbo_D_ORDERADDRESS].[ADDRESS_ORGID] [ADDRESS_ORGID]
FROM
(
SELECT CAST(1 AS numeric(38)) AS ID, CAST(CVCOUNTRY AS int) AS cvcountry, ADDRESS_ORGID, ORDERLINE_ORGID, ORDER_ORGID, CVADDRESSTYPE, IDWSOURCEID,
LORDERID, IORDERLINENO, SZNAME1, SZNAME2, SZNAME3, SZROAD1, SZROAD2, SZROAD3, SZPOSTCODE, SZTOWN, SZPHONE, SZFAX, SZCONTACTPERSON,
SZEMAIL, SZVATID, SZINVCUSNO, SZCOUNTRYCODE
FROM D_ORDERADDRESS_NEW
) [dbo_D_ORDERADDRESS]
) [dbo_D_ORDERADDRESS] ON ([f_orders].[DELADDRESS_ORGID] = [dbo_D_ORDERADDRESS].[ADDRESS_ORGID] OR [f_orders].[DELADDRESS_ORGID] IS NULL AND [dbo_D_ORDERADDRESS].[ADDRESS_ORGID] IS NULL)
LEFT OUTER JOIN (
SELECT
[D_FRAMESIZE].[Framesize] [Framesize],
[D_PRODUCT_NEW].[SZGENCODE] [Generationcode],
[D_PRODTYPE].[MotorsProductType] [MotorsProductType],
[D_PRODTYPE].[MotorsProdType] [MotorsProdType],
[D_PRODUCT_NEW].[DWBOBJECTOID] [DWBOBJECTOID]
FROM
[dbo].[D_PRODUCT_NEW] [D_PRODUCT_NEW]
LEFT OUTER JOIN (
SELECT
[D_FRAMESIZE].[DESCRIPTIONEN] [Framesize],
[D_FRAMESIZE].[VALUE] [VALUE]
FROM
[dbo].[D_FRAMESIZE] [D_FRAMESIZE]
) [D_FRAMESIZE] ON [D_PRODUCT_NEW].[CVFRAMESIZE] = [D_FRAMESIZE].[VALUE]
LEFT OUTER JOIN (
SELECT
[D_PRODTYPE].[SZMDPRODTYPE] [MotorsProductType],
[D_PRODTYPE].[SZMDPRODTYPE] [MotorsProdType],
[D_PRODTYPE].[VALUE] [VALUE]
FROM
[dbo].[D_PRODTYPE] [D_PRODTYPE]
) [D_PRODTYPE] ON [D_PRODUCT_NEW].[CVPRODTYPE] = [D_PRODTYPE].[VALUE]
) [D_PRODUCT_NEW] ON ([f_orders].[DWPRDOID] = [D_PRODUCT_NEW].[DWBOBJECTOID] OR [f_orders].[DWPRDOID] IS NULL AND [D_PRODUCT_NEW].[DWBOBJECTOID] IS NULL)
LEFT OUTER JOIN (
SELECT
[D_BALIDINFO].[SZSOPREGION] [SRUSOPRegion],
[D_BALIDINFO].[SZCOUNTRY] [SRUCountry],
[D_BALIDINFO].[SZALTERNATEID] [SRU],
[D_BALIDINFO].[SZALTERNATEID] [SZALTERNATEID],
[D_BALIDINFO].[SZSOPREGION] [SOPRegion],
[D_BALIDINFO].[DWBOBJECTOID] [DWBOBJECTOID]
FROM
[dbo].[D_BALIDINFO] [D_BALIDINFO]
) [D_BALIDINFO] ON [f_orders].[DWSALESRESPONSIBLEUNITOID] = [D_BALIDINFO].[DWBOBJECTOID]
LEFT OUTER JOIN (
SELECT
[D_PU].[DESCRIPTIONEN] [PU],
[D_PU].[DESCRIPTIONEN] [PU2],
[D_PU].[VALUE] [VALUE]
FROM
[dbo].[D_PU] [D_PU]
) [D_PU] ON [f_orders].[CVPU] = [D_PU].[VALUE]
LEFT OUTER JOIN (
SELECT
[D_WAREHOUSE].[DESCRIPTIONEN] [Warehouse],
[D_WAREHOUSE].[DESCRIPTIONEN] [Warehouse2],
[D_WAREHOUSE].[VALUE] [VALUE]
FROM
[dbo].[D_WAREHOUSE] [D_WAREHOUSE]
) [D_WAREHOUSE] ON [f_orders].[CVWAREHOUSEID] = [D_WAREHOUSE].[VALUE]
LEFT OUTER JOIN (
SELECT
[D_FRAMESIZE].[DESCRIPTIONEN] [Framesize1],
[D_FRAMESIZE].[DESCRIPTIONEN] [FrameSize],
[D_FRAMESIZE].[VALUE] [VALUE]
FROM
[dbo].[D_FRAMESIZE] [D_FRAMESIZE]
) [D_FRAMESIZE] ON [f_orders].[CVFRAMESIZE] = [D_FRAMESIZE].[VALUE]
LEFT OUTER JOIN (
SELECT
[D_PRODGROUP].[DESCRIPTIONEN] [Productgroup],
[D_PRODGROUP].[DESCRIPTIONEN] [ProductGroup2],
[D_PRODGROUP].[VALUE] [VALUE]
FROM
[dbo].[D_PRODGROUP] [D_PRODGROUP]
) [D_PRODGROUP] ON [f_orders].[CVPRODGROUP] = [D_PRODGROUP].[VALUE]
LEFT OUTER JOIN (
SELECT
[D_PRODTYPE].[DESCRIPTIONEN] [Producttype],
[D_PRODTYPE].[DESCRIPTIONEN] [ProductType2],
[D_PRODTYPE].[VALUE] [VALUE]
FROM
[dbo].[D_PRODTYPE] [D_PRODTYPE]
) [D_PRODTYPE] ON [f_orders].[CVPRODTYPE] = [D_PRODTYPE].[VALUE]
INNER JOIN (
SELECT
[S_SECURITY].[Login_Name] [LoginName],
[S_SECURITY].[Security_ID] [Security_ID]
FROM
[dbo].[S_SECURITY] [S_SECURITY]
) [S_SECURITY] ON [f_orders].[SECURITY_ID2] = [S_SECURITY].[Security_ID]
LEFT OUTER JOIN (
SELECT
[D_ORDERTYPE].[DESCRIPTIONEN] [OrderType],
[D_ORDERTYPE].[VALUE] [VALUE]
FROM
[dbo].[D_ORDERTYPE] [D_ORDERTYPE]
) [D_ORDERTYPE] ON [f_orders].[CVORDERTYPE] = [D_ORDERTYPE].[VALUE]
LEFT OUTER JOIN (
SELECT
[D_LINEORDERTYPE].[DESCRIPTIONEN] [LineOrderType],
[D_LINEORDERTYPE].[VALUE] [VALUE]
FROM
[dbo].[D_LINEORDERTYPE] [D_LINEORDERTYPE]
) [D_LINEORDERTYPE] ON [f_orders].[CVLINEORDERTYPE] = [D_LINEORDERTYPE].[VALUE]
LEFT OUTER JOIN (
SELECT
[A_ExchangeRates].[USDRate] [USDRate],
[A_ExchangeRates].[CVCurrency] [CVCurrency],
[A_ExchangeRates].[RateDate] [RateDate]
FROM
[dbo].[A_ExchangeRates] [A_ExchangeRates]
) [A_ExchangeRates] ON [f_orders].[CVCURRENCY] = [A_ExchangeRates].[CVCurrency] AND [f_orders].[DATE_OrderBookedatSU] = [A_ExchangeRates].[RateDate]
LEFT OUTER JOIN (
SELECT
[D_TYPEOFORDHAND].[DESCRIPTIONEN] [Typeoforderhandling],
[D_TYPEOFORDHAND].[VALUE] [VALUE]
FROM
[dbo].[D_TYPEOFORDHAND] [D_TYPEOFORDHAND]
) [D_TYPEOFORDHAND] ON [f_orders].[CVTYPEOFORDHAND] = [D_TYPEOFORDHAND].[VALUE]
GROUP BY
[f_orders].[LORDEREDQTY], [dbo_D_ORDERADDRESS].[Countrycode], [D_PRODUCT_NEW].[Framesize],
[f_orders].[SZCUSSHORTNAME], [f_orders].[SZCUSNO], [D_PRODUCT_NEW].[Generationcode],
[D_BALIDINFO].[SRUSOPRegion], [D_BALIDINFO].[SRUCountry], [D_PU].[PU], [D_BALIDINFO].[SRU], [D_WAREHOUSE].[Warehouse], [f_orders].[DATE_OrderBookedatSU], [f_orders].[DTCONFIRMEDDEL],
[D_PRODUCT_NEW].[MotorsProductType], [f_orders].[SZORDERNO], [f_orders].[IORDERLINENO], [D_FRAMESIZE].[Framesize1],
[D_PRODGROUP].[Productgroup], [D_PRODTYPE].[Producttype], [f_orders].[SZPRODNO],
CASE WHEN COALESCE(LEN([f_orders].[SZVARIANTCODE]), 0) = 0 THEN CAST([f_orders].[IVARIANTCODENO] AS VARCHAR(255)) ELSE [f_orders].[SZVARIANTCODE] END,
[f_orders].[IVARIANTIDX], [f_orders].[DATE_OrderBookedatSU], [f_orders].[DATE_OrderBookedatSU], D_TYPEOFORDHAND.Typeoforderhandling
1.通过嵌套循环增加估计的数据大小是正常的,对性能没有任何影响？
2.我使用了大约20个分组列,它似乎对查询成本影响最大.有可能取代这个哈希比赛吗？
最佳答案 确定您的查询看起来相当复杂,并且很可能使优化器混乱,或许查看统计信息以查看是否可以使用完全扫描来帮助优化器.考虑使用临时表来嵌套嵌套连接,以便只放置所需的列.还要考虑在主表f_orders上为此添加索引以减少表扫描.
