SQL Server中怎么改写内联表值函数

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问题 SQL：

SELECT TOP 1001 ha.HuntApplicationID ,
 ha.PartyNumber ,
 mht.Name AS MasterHuntTypeName ,
 htly.LicenseYear ,
 lStatus.[Status] AS DrawTicketStatus ,
 isnull(dbo.udf_GetHuntApplicationPartyCount(ha.HuntApplicationID), 0) AS MemberCount ,
 count( won.DrawTicketLicenseID) AS DrawnMemberCount ,
 won.drawticketid ,
 dt.PreDrawNonResidentMemberCount AS NRMemberCount ,
 dbo.udf_GetAvgPreferencePoints(dt.DrawTicketID) AS PreferencePointAverage ,
 CASE
 WHEN ha.Quantity   1 THEN NULL
 ELSE dt.PreDrawRandomNumber
 END AS PreDrawRandomNumber ,
 dsm.Name AS DrawSelectionMethodName ,
 dt.DrawnSequence ,
 dt.PreferencePointRank ,
 dt.DrawID ,
 dt.RandomRank
FROM dbo.HuntApplication ha
JOIN dbo.HuntTypeLicenseYear htly ON ha.HuntTypeLicenseYearID = htly.HuntTypeLicenseYearID
JOIN dbo.MasterHuntType mht ON htly.MasterHuntTypeID = mht.MasterHuntTypeID
LEFT JOIN dbo.HuntApplicationLicense hal ON ha.HuntApplicationID = hal.HuntApplicationID
LEFT JOIN dbo.DrawTicket dt ON ha.HuntApplicationID = dt.HuntApplicationID
LEFT JOIN dbo.DrawTicketLicense won ON dt.DrawTicketID = won.DrawTicketID
AND won.WasDrawn = 1
LEFT JOIN dbo.DrawSelectionMethod dsm ON dt.DrawSelectionMethodID = dsm.DrawSelectionMethodID
LEFT JOIN dbo.StatusCode lStatus ON dt.StatusCodeID = lStatus.StatusCodeID
JOIN dbo.DrawTicketHuntChoice dthc ON dt.DrawTicketID = dthc.DrawTicketID
CROSS APPLY dbo.tvf_GetHuntApplicationPartyCount(ha.HuntApplicationID) hapc
CROSS APPLY dbo.tvf_GetAvgPreferencePoints(dt.DrawTicketID) app
WHERE 1 = 1
 AND htly.MasterHuntTypeID = @iMasterHuntTypeID
 AND htly.LicenseYear = @iLicenseYear
 AND dt.StatusCodeID = @iDrawTicketStatusCodeID
 AND dthc.WasDrawn = @iHuntChoiceWasDrawn
GROUP BY ha.HuntApplicationID,
 ha.PartyNumber,
 mht.[Name],
 htly.LicenseYear,
 lStatus.[Status],
 isnull(dbo.udf_GetHuntApplicationPartyCount(ha.HuntApplicationID), 0),
 won.DrawTicketID,
 dt.PreDrawNonResidentMemberCount,
 dbo.udf_GetAvgPreferencePoints(dt.DrawTicketID),
 CASE
 WHEN ha.Quantity   1 THEN NULL
 ELSE dt.PreDrawRandomNumber
 END,
 dsm.[Name],
 dt.DrawnSequence,
 dt.PreferencePointRank,
 dt.DrawID,
 dt.RandomRank
ORDER BY htly.LicenseYear DESC,
 mht.Name,
 lStatus.[Status],
 dt.DrawID,
 PreferencePointAverage DESC,
 PreDrawRandomNumber,
 ha.PartyNumber

静态函数：

CREATE FUNCTION [dbo].[udf_GetAvgPreferencePoints]
(@DrawTicketID INT)
RETURNS NUMERIC (18, 3)
BEGIN
 RETURN
 SELECT TOP 1
 CONVERT(DECIMAL, dt.PreDrawPreferencePointTotal) / NULLIF(CONVERT(DECIMAL, dt.PreDrawMemberCount),0)
 FROM dbo.DrawTicket dt
 WHERE dt.DrawTicketID = @DrawTicketID
END

执行时间 40s

这是典型可以进行静态函数改写内联表值函数的 sql：

改写后：

SELECT TOP 1001 ha.HuntApplicationID ,
 ha.PartyNumber ,
 mht.Name AS MasterHuntTypeName ,
 htly.LicenseYear ,
 lStatus.[Status] AS DrawTicketStatus ,
 --isnull(dbo.udf_GetHuntApplicationPartyCount(ha.HuntApplicationID), 0) AS MemberCount ,
  isnull(hapc.MemberCount, 0) AS MemberCount,
 count( won.DrawTicketLicenseID) AS DrawnMemberCount ,
 won.drawticketid ,
 dt.PreDrawNonResidentMemberCount AS NRMemberCount ,
 --dbo.udf_GetAvgPreferencePoints(dt.DrawTicketID) AS PreferencePointAverage ,
  app.PreferencePointAverage PreferencePointAverage,
 CASE
 WHEN ha.Quantity   1 THEN NULL
 ELSE dt.PreDrawRandomNumber
 END AS PreDrawRandomNumber ,
 dsm.Name AS DrawSelectionMethodName ,
 dt.DrawnSequence ,
 dt.PreferencePointRank ,
 dt.DrawID ,
 dt.RandomRank
FROM dbo.HuntApplication ha
JOIN dbo.HuntTypeLicenseYear htly ON ha.HuntTypeLicenseYearID = htly.HuntTypeLicenseYearID
JOIN dbo.MasterHuntType mht ON htly.MasterHuntTypeID = mht.MasterHuntTypeID
LEFT JOIN dbo.HuntApplicationLicense hal ON ha.HuntApplicationID = hal.HuntApplicationID
LEFT JOIN dbo.DrawTicket dt ON ha.HuntApplicationID = dt.HuntApplicationID
LEFT JOIN dbo.DrawTicketLicense won ON dt.DrawTicketID = won.DrawTicketID
AND won.WasDrawn = 1
LEFT JOIN dbo.DrawSelectionMethod dsm ON dt.DrawSelectionMethodID = dsm.DrawSelectionMethodID
LEFT JOIN dbo.StatusCode lStatus ON dt.StatusCodeID = lStatus.StatusCodeID
JOIN dbo.DrawTicketHuntChoice dthc ON dt.DrawTicketID = dthc.DrawTicketID
CROSS APPLY dbo.tvf_GetHuntApplicationPartyCount(ha.HuntApplicationID) hapc
CROSS APPLY dbo.tvf_GetAvgPreferencePoints(dt.DrawTicketID) app
WHERE 1 = 1
 AND htly.MasterHuntTypeID = @iMasterHuntTypeID
 AND htly.LicenseYear = @iLicenseYear
 AND dt.StatusCodeID = @iDrawTicketStatusCodeID
 AND dthc.WasDrawn = @iHuntChoiceWasDrawn
GROUP BY ha.HuntApplicationID,
 ha.PartyNumber,
 mht.[Name],
 htly.LicenseYear,
 lStatus.[Status],
 --isnull(dbo.udf_GetHuntApplicationPartyCount(ha.HuntApplicationID), 0),
  isnull(hapc.MemberCount, 0),
 won.DrawTicketID,
 dt.PreDrawNonResidentMemberCount,
 --dbo.udf_GetAvgPreferencePoints(dt.DrawTicketID),
  app.PreferencePointAverage,
 CASE
 WHEN ha.Quantity   1 THEN NULL
 ELSE dt.PreDrawRandomNumber
 END,
 dsm.[Name],
 dt.DrawnSequence,
 dt.PreferencePointRank,
 dt.DrawID,
 dt.RandomRank
ORDER BY htly.LicenseYear DESC,
 mht.Name,
 lStatus.[Status],
 dt.DrawID,
 PreferencePointAverage DESC,
 PreDrawRandomNumber,
 ha.PartyNumber

对应的表值函数：

CREATE FUNCTION [dbo].[tvf_GetAvgPreferencePoints]
(@DrawTicketID INT)
RETURNS TABLE WITH SCHEMABINDING
RETURN
 SELECT TOP 1
 CONVERT(DECIMAL, dt.PreDrawPreferencePointTotal) / NULLIF(CONVERT(DECIMAL, dt.PreDrawMemberCount),0) as PreferencePointAverage
 FROM dbo.DrawTicket dt
 WHERE dt.DrawTicketID = @DrawTicketID
GO

改写后执行时间从 40s 降低到 16s，对于倾斜列的优化速度更为明显

感谢各位的阅读，以上就是“SQL Server 中怎么改写内联表值函数”的内容了，经过本文的学习后，相信大家对 SQL Server 中怎么改写内联表值函数这一问题有了更深刻的体会，具体使用情况还需要大家实践验证。这里是丸趣 TV，丸趣 TV 小编将为大家推送更多相关知识点的文章，欢迎关注！