SQL Server Management Studio中2008 R2派生表where子句優化
我有一個觀點(相當漫長的SQL代碼是一系列派生表)所使用的運行查詢幾個不同的用戶和〜4000000存儲過程記錄。以下查詢在大約10分鐘內執行。
Select * from dbo.[vw_name]
我試圖使用同樣的觀點拉動信息1分的記錄,但查詢仍然需要〜10分鐘:
Select * from dbo.[vw_name] where ln=1234567890
它好像在視圖處理所有400萬次的記錄和然後應用我的where子句。我能夠將視圖複製到一個表值函數中,並將單個記錄的查詢時間增加到〜10秒(我假設我能夠在第一個派生表中插入where子句而不是在結束)。有關如何強制優化器在查詢視圖時首先考慮where子句的想法?
添加視圖查詢:
SELECT AsOfDate=GETDATE()
,A1.*
,Onsite_Flag= CASE
WHEN A1.[columnname]=1 AND A1.[columnname]=0 THEN 1
WHEN A1.[columnname]=5 AND A1.[columnname]=0 THEN 1
WHEN A1.[columnname] IN (12,31,33,34,35,38,52,54,59) THEN 1
ELSE 0
END
,A1.Allowable_Flag
,Achieved_Flag= CASE
WHEN A1.[columnname]=1 THEN
CASE
WHEN A1.[columnname] LIKE 'name%'
AND A1.[columnname]>=A1.[columnname]
AND (A1.[columnname] LIKE '%LOL%' OR A1.[columnname]='test') THEN 1
WHEN A1.[columnname]='qwerw' AND A1.[columnname]=4 THEN 1
WHEN A1.[columnname]='aerr33' AND A1.[columnname]=4 THEN 1
WHEN A1.[columnname]='asdf45' AND A1.[columnname] IS NOT NULL THEN 1
ELSE 0
END
ELSE 0
END
,IM_Flag= CASE
WHEN A1.[columnname] IN(12,38) THEN 1
WHEN A1.[columnname]=1 AND A1.[columnname]=24 THEN 1
ELSE 0
END
FROM (SELECT [columnname]....
,[Name]=LTRIM(RTRIM(V1.A1FNAM)) + ' ' + LTRIM(RTRIM(V1.A1LNAM))
,LocationType= CASE WHEN LH1.[columnname]=2 THEN nLT.[columnname] ELSE LT.[columnname] END
,LocationTypeID=CASE WHEN LH1.[columnname]=2 THEN nLT.[columnname] ELSE LT.[columnname] END
,Location=CASE
WHEN DLD1.[columnname] IS NULL THEN DLD1.[columnname]
WHEN LH1.[columnname] IN (2,8) THEN DLD1.[columnname] + ' - ' + DLD2.[columnname]
ELSE DLD1.[columnname]
END
,Allowable_Flag= CASE
WHEN CU1.[columnname]='1234' THEN 1
WHEN FCM.[columnname]='Y' THEN 0
WHEN MLD.[columnname]='24' THEN 0
WHEN INV.[columnname] LIKE '436573456%' THEN 1
WHEN INV.[columnname] LIKE '4526%' THEN 1
WHEN DSR.[columnname]='1020' THEN 1
ELSE 0
END
,RN=ROW_NUMBER()OVER(PARTITION BY L.LoanNumber ORDER BY (CASE WHEN DM.Departments_ID=24 THEN 1 ELSE 0 END) DESC,LH1.LocationDate DESC)
FROM server_name_3.dbo.[tablename] DSR
LEFT JOIN ....
OUTER APPLY SERVER_name_2.dbo.fnc_DT (LH1.[columnname], LH1.[columnname]) DLD1
OUTER APPLY SERVER_name_2.dbo.fnc_DT (DLD1.[columnname], DLD1.[columnname]) DLD2
LEFT JOIN (SELECT field1, field2,...
FROM server_name_3.dbo.SRVDSR DSR
LEFT JOIN ...
INNER JOIN (SELECT field1, MAX(field2) as field2 FROM SERVERNAME1.dbo.[tablename] WHERE field3=157 GROUP BY field1) CUO ON CUO.field1=R.field1
GROUP BY DSR.field1
) CP_Req ON DSR.field1=CP_Req.field1
) A1
WHERE A1.RN=1
請參閱http://www.databasejournal.com/features/mssql/article.php/3867651/SQL-Server-Indexed-Views.htm –
我無法SCHEMABIND視圖,因爲它擊中多個數據庫 – Czar