如何加快160萬行上的聚簇索引掃描速度？

我有一張超過160萬條記錄的表格。（在下面創建語句。）我使用主鍵在查詢中加入它，查詢需要4秒，其中61％用於此表上的集羣索引掃描。如何加快160萬行上的聚簇索引掃描速度？

下面是該查詢的樣本：

DECLARE  @pintDueBy    DATETIME = '1/1/1900', 
    @pintCounty    INT = 0 

SET @pintDueBy = N'10/30/14' 
SET @pintCounty = 42043 

SELECT 
ISNULL(Eqp.ELOFLNUM,0) AS ELOFLNUM 
,ISNULL(Eqp.ELERPNUM, 0) AS ELERPNUM 
,ISNULL(CASE 
      WHEN Eqp.ELERPNUM IS NULL OR Eqp.ELERPNUM = 0 THEN Eqp.ELOFLNUM 
      ELSE Eqp.ELERPNUM 
     END, 0) AS OwnFLNUM 
,ISNULL(RpOwn.T_AS400_ELVPOWN00_ID,0) AS RespOwn_ID 
,ISNULL(Eqp.ELBLDGCD,0) AS ELBLDGCD 
,ISNULL(Eqp.ELEEQNO,0) AS ELEEQNO 
,ISNULL(Eqp.ELPERMTNO,0) AS ELPERMTNO 
,ISNULL(Eqp.ELEPERMID,'') AS ELEPERMID 
,ISNULL(ELEYCEXP,0) AS ELEYCEXP 
,ISNULL(ELEMCEXP,0) AS ELEMCEXP 
, BOISdbo.UDF_PARSE_DATE_FIELDS(NULL,ELEYCEXP,ELEMCEXP,99) AS ELECertExp 
, BOISdbo.UDF_PARSE_DATE_FIELDS(NULL,LastInsp.ELDTINSYY,LastInsp.ELDTINSMM,LastInsp.ELDTINSDD) AS LastSeen 
, ISNULL(LastInsp.ELERSLT1, '') AS LastSeenResult 
,Eqp.T_AS400_ELVPEQP00_ID AS EqpID 
,ISNULL(Eqp.ELEECOCD_ID,0) AS ELEECOCD_ID 
,ISNULL(Eqp.ELEEORIG_ID,0) AS ELEEORIG_ID 
,ISNULL(Eqp.LAST_INSPTN_ID,0) AS LAST_INSPTN_ID 
    , ISNULL(LastInsp.INVID,0) AS INVID 
FROM dbo.T_AS400_ELVPEQP00    AS Eqp 
    LEFT JOIN dbo.T_AS400_ELVPLOC00   AS Loc 
     ON Eqp.ELBLDGCD = Loc.ELBLDGCD 
    LEFT JOIN dbo.T_AS400_ELVPOWN00   AS RpOwn 
     ON CASE 
        WHEN Eqp.ELERPNUM IS NULL OR Eqp.ELERPNUM = 0 THEN Eqp.ELOFLNUM 
        ELSE Eqp.ELERPNUM 
       END = RpOwn.ELOFLNUM 
    LEFT JOIN dbo.T_AS400_ELVPINS00    AS LastInsp 
     ON Eqp.LAST_INSPTN_ID = LastInsp.T_AS400_ELVPINS00_ID 
    LEFT JOIN BOISdbo.UV_COUNTY_LIST AS cnty 
     ON cnty.REF_VALUE = Loc.ELLCNTY 
WHERE 
    Loc.ELLSTATS IN ('O') -- O - Occupied 
    AND 
    ISNULL(LastInsp.ELERSLT1, '') NOT IN ('O') -- O - Out of Service 
    AND 
    (@pintCounty = 0 OR cnty.REF_VALUE = @pintCounty)

我這個查詢輸出列表僅使用領域的6：

[BOIS].[dbo].[T_AS400_ELVPINS00].ELDTINSYY 
[BOIS].[dbo].[T_AS400_ELVPINS00].ELDTINSMM 
[BOIS].[dbo].[T_AS400_ELVPINS00].ELDTINSDD 
[BOIS].[dbo].[T_AS400_ELVPINS00].ELERSLT1 
[BOIS].[dbo].[T_AS400_ELVPINS00].T_AS400_ELVPINS00_ID 
[BOIS].[dbo].[T_AS400_ELVPINS00].INVID

任何想法？

CREATE TABLE [dbo].[T_AS400_ELVPINS00](
    [ELBLDGCD] [int] NULL, 
    [ELEEQNO] [int] NULL, 
    [ELDTINSYY] [int] NULL, 
    [ELDTINSMM] [int] NULL, 
    [ELDTINSDD] [int] NULL, 
    [ELINSCD] [varchar](6) NULL, 
    [ELFEECO] [varchar](6) NULL, 
    [ELIINSR] [varchar](6) NULL, 
    [ELERSLT1] [varchar](1) NULL, 
    [ELDTIBYY] [int] NULL, 
    [ELDTIBMM] [int] NULL, 
    [ELDTIBDD] [int] NULL, 
    [ELECRDTYY] [int] NULL, 
    [ELECRDTMM] [int] NULL, 
    [ELECRDTDD] [int] NULL, 
    [ELTINSP] [varchar](1) NULL, 
    [ELECNUM] [int] NULL, 
    [ELEFEE] [decimal](18, 0) NULL, 
    [ELEBILL] [varchar](1) NULL, 
    [ELDUPCT] [varchar](1) NULL, 
    [ELDTDUPYY] [int] NULL, 
    [ELDTDUPMM] [int] NULL, 
    [ELDTDUPDD] [int] NULL, 
    [ELEFLG] [varchar](1) NULL, 
    [ELFORCD] [varchar](1) NULL, 
    [ELEINV] [varchar](8) NULL, 
    [ELELSEAL] [varchar](1) NULL, 
    [ELELSDTY] [int] NULL, 
    [ELELSDTM] [int] NULL, 
    [ELELSDTD] [int] NULL, 
    [ELELSNUM] [int] NULL, 
    [ELREMVYY] [int] NULL, 
    [ELREMVMM] [int] NULL, 
    [ELREMVDD] [int] NULL, 
    [ELEDFNCS] [varchar](1) NULL, 
    [ELEDFNCDA] [varchar](5) NULL, 
    [ELERFLDA] [varchar](1) NULL, 
    [ELEDFNCDB] [varchar](5) NULL, 
    [ELERFLDB] [varchar](1) NULL, 
    [ELEDFNCDC] [varchar](5) NULL, 
    [ELERFLDC] [varchar](1) NULL, 
    [ELEDFNCDD] [varchar](5) NULL, 
    [ELERFLDD] [varchar](1) NULL, 
    [ELEDFNCDE] [varchar](5) NULL, 
    [ELERFLDE] [varchar](1) NULL, 
    [ELEDFNCDF] [varchar](5) NULL, 
    [ELERFLDF] [varchar](1) NULL, 
    [ELEDFNCDG] [varchar](5) NULL, 
    [ELERFLDG] [varchar](1) NULL, 
    [ELEDFNCDH] [varchar](5) NULL, 
    [ELERFLDH] [varchar](1) NULL, 
    [ELEDFNCDI] [varchar](5) NULL, 
    [ELERFLDI] [varchar](1) NULL, 
    [ELEDFNCDJ] [varchar](5) NULL, 
    [ELERFLDJ] [varchar](1) NULL, 
    [ELEDFNCDK] [varchar](5) NULL, 
    [ELERFLDK] [varchar](1) NULL, 
    [ELEDFNCDL] [varchar](5) NULL, 
    [ELERFLDL] [varchar](1) NULL, 
    [ELEDFNCDM] [varchar](5) NULL, 
    [ELERFLDM] [varchar](1) NULL, 
    [ELEDFNCDN] [varchar](5) NULL, 
    [ELERFLDN] [varchar](1) NULL, 
    [ELEDFNCDO] [varchar](5) NULL, 
    [ELERFLDO] [varchar](1) NULL, 
    [ELEDFNCDP] [varchar](5) NULL, 
    [ELERFLDP] [varchar](1) NULL, 
    [ELEDFNCDQ] [varchar](5) NULL, 
    [ELERFLDQ] [varchar](1) NULL, 
    [ELEDFNCDR] [varchar](5) NULL, 
    [ELERFLDR] [varchar](1) NULL, 
    [ELEDFNCDS] [varchar](5) NULL, 
    [ELERFLDS] [varchar](1) NULL, 
    [ELEDFNCDT] [varchar](5) NULL, 
    [ELERFLDT] [varchar](1) NULL, 
    [ELEIUPDTY] [int] NULL, 
    [ELEIUPDTM] [int] NULL, 
    [ELEIUPDTD] [int] NULL, 
    [ELESCLTR] [varchar](1) NULL, 
    [ELEDTCOY] [int] NULL, 
    [ELEDTCOM] [int] NULL, 
    [ELEDTCOD] [int] NULL, 
    [ELDTORDY] [int] NULL, 
    [ELDTORDM] [int] NULL, 
    [ELDTORDD] [int] NULL, 
    [ELDTRPRY] [int] NULL, 
    [ELDTRPRM] [int] NULL, 
    [ELDTRPRD] [int] NULL, 
    [ELERPRCD] [varchar](1) NULL, 
    [ELSTRHH] [int] NULL, 
    [ELSTRMM] [int] NULL, 
    [ELSTRSS] [int] NULL, 
    [ELSTPHH] [int] NULL, 
    [ELSTPMM] [int] NULL, 
    [ELSTPSS] [int] NULL, 
    [ELDTCLRYY] [int] NULL, 
    [ELDTCLRMM] [int] NULL, 
    [ELDTCLRDD] [int] NULL, 
    [ELIUSER] [varchar](10) NULL, 
    [ELIKEYID] [varchar](1) NULL, 
    [T_AS400_ELVPINS00_ID] [int] IDENTITY(1,1) NOT NULL, 
    [DOC_LINK_ID] [int] NULL, 
    [CRTD_BY] [varchar](30) NOT NULL, 
    [CRTD_DT] [datetime] NOT NULL, 
    [MODFD_BY] [varchar](30) NULL, 
    [MODFD_DT] [datetime] NULL, 
    [INVID] [int] NULL, 
    [PARENT_INSPTN_ID] [int] NULL, 
    [ELEEQP_ID] [int] NULL, 
    [COMMENTS] [varchar](1500) NULL, 
    [ELFEECO_ID] [int] NULL, 
    [T_AS400_ELVPAPP0_ID] [int] NULL, 
CONSTRAINT [PK_T_AS400_ELVPINS00] PRIMARY KEY CLUSTERED 
(
    [T_AS400_ELVPINS00_ID] ASC 
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY] 
) ON [PRIMARY] 

GO

來源

2014-10-31 M Kenyon II

將[執行計劃]（http://stackoverflow.com/a/7359705/562459）粘貼到您的問題中。 – 2014-10-31 17:52:21

你如何限制你的查詢中返回的記錄？如果你選擇的是「全部」主鍵，我認爲你不會去掃描 – Kritner 2014-10-31 17:52:23

根據你的查詢，你可以嘗試把索引放在你需要的那六列 - 然後也許你會得到一個更便宜，更精簡的非聚簇索引掃描，而不是聚簇索引（=表）掃描 – 2014-10-31 18:14:08

如果您有內聯函數您的選擇：

BOISdbo.UDF_PARSE_DATE_FIELDS(NULL,ELEYCEXP,ELEMCEXP,99)

替換這些功能與實際的代碼，在函數調用....這將是遠離漂亮，但應該執行更好。

來源

2014-10-31 18:48:53

如何加快160萬行上的聚簇索引掃描速度？

回答

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