stored-procedures - 重新编译后存储过程运行速度快

Question

我对 SQL Server 2008 R2 上的存储过程有一个非常奇怪的问题。有时，大约每个月一次，我有一个程序变得非常慢，运行大约需要 6 秒而不是几毫秒。但是如果我简单地重新编译它，不做任何改变，它会再次快速运行。
它不会发生在所有存储过程上，只有一个(服务器上有数百个)。

我的猜测是在编译 sp 时，它会被缓存，并且每次我调用它时都会重用这个缓存，并且这个缓存版本由于某种原因被破坏了。

我希望也许有些人已经遇到过这种问题，或者至少可以为我指明正确的方向，比如 SQL Server 或 IIS 的哪些配置会影响存储过程缓存？

这是代码:

USE [MyBaseName]
GO
/****** Object:  StoredProcedure [dbo].[Publication_getByCriteria]    Script Date: 05/29/2013 12:11:07 ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
ALTER PROCEDURE [dbo].[Publication_getByCriteria]
    @id_sousTheme As int = null,
    @id_theme As int = null,
    @nbPubli As int = 1000000,
    @bActuSite As bit = null,
    @bActuPerso As bit = null,
    @bActuNewsletter As bit = null,
    @bActuChronique As bit = null,
    @bActuVideo As bit = null,
    @bActuVideoBuzz As bit = null,
    @bActuOpportunite As bit = null,
    @id_contact As int = null,
    @bOnlyPublished As bit = 0,
    @bOnlyForHomePage as bit = 0,
    @id_contactForTheme As int = null,
    @id_newsletter As int = null,
    @ID_ActuChronique As int = null,
    @sMotClef As varchar(500) = null,
    @sMotClefForFullText as varchar(500) = '""',
    @dtPublication As datetime = null,  
    @bParlonsFinance As bit = null,
    @bPartenaires as bit = null,
    @bUne As bit = null,
    @bEditoParlonsFinance As bit = null,
    @bEditoQuestionFonds as bit = null,
    @dtDebPublication As datetime = null,
    @dtFinPublication As datetime = null,
    @bOnlyActuWithDroitReponse As bit = 0,
    @bActuDroitReponse As bit = null
AS
BEGIN
    SET NOCOUNT ON;

    DECLARE @dtNow As datetime
    SET @dtNow = GETDATE()

    SELECT TOP (@nbPubli) p.id_publication, p.sTitre, p.sTexte, p.sTexteHTML, p.dtPublication, p.id_linkedDroitReponse,
        si.id_actusite, pe.id_actuPerso, ne.id_actuNewsletter, ac.id_actuChronique, av.id_actuVideo, ap.id_actuOpportunite, ad.id_actuDroitReponse,
        c.ID_Contact, c.sPhotoCarre, NULL As sTypePubli, n.id_newsletter, 
        dbo.Publication_get1Theme(p.id_publication) As theme,
        CAST(CASE WHEN ad.id_actuDroitReponse IS NULL THEN 0 ELSE 1 END As bit) As bIsDroitReponse,
        coalesce(Personne.sNom, Societe.sNom) as sNom, Personne.sPrenom
    FROM Publication p
        LEFT OUTER JOIN ActuSite si ON p.id_publication = si.id_publication
        LEFT OUTER JOIN ActuPerso pe ON p.id_publication = pe.id_publication
        LEFT OUTER JOIN ActuNewsletter ne ON p.id_publication = ne.id_publication
        LEFT OUTER JOIN ActuChronique ac ON p.id_publication = ac.id_publication
        LEFT OUTER JOIN ActuVideo av ON p.id_publication = av.id_publication
        LEFT OUTER JOIN ActuOpportunite ap ON p.id_publication = ap.id_publication
        LEFT OUTER JOIN ActuDroitReponse ad ON p.id_publication = ad.id_publication
        LEFT OUTER JOIN Contact c ON p.id_contact = c.ID_Contact
        LEFT OUTER JOIN Personne ON Personne.id_contact = c.id_contact
        LEFT OUTER JOIN Societe ON Societe.id_contact = c.id_contact
        LEFT OUTER JOIN Newsletter n ON ne.id_actuNewsletter = n.id_actuNewsletter
    WHERE p.bSupp = 0
    AND (@bOnlyPublished = 0 Or (@bOnlyPublished = 1 AND p.dtPublication IS NOT NULL AND p.dtPublication < @dtNow))
    AND (@id_sousTheme IS NULL Or p.id_publication IN(SELECT id_publication FROM PubliSousTheme WHERE id_soustheme = @id_sousTheme))
    AND (@id_theme IS NULL Or p.id_publication IN(SELECT id_publication FROM PubliTheme WHERE id_theme = @id_theme))
    AND ((@bActuSite = 1 AND si.id_actusite IS NOT NULL)
            OR (@bActuPerso = 1 AND pe.id_actuPerso IS NOT NULL)
            OR (@bActuNewsletter = 1 AND ne.id_actuNewsletter IS NOT NULL)
            OR (@bActuChronique = 1 AND ac.id_actuChronique IS NOT NULL)
            OR (@bActuVideo = 1 AND av.id_actuVideo IS NOT NULL)
            OR (@bActuVideoBuzz = 1 AND av.id_actuVideo IS NOT NULL and coalesce(av.sBuzz, '') <> '' )
            OR (@bActuOpportunite = 1 AND ap.id_actuOpportunite IS NOT NULL)
            OR (@bActuDroitReponse = 1 AND ad.id_actuDroitReponse IS NOT NULL))
    AND (@id_contact IS NULL Or p.id_contact = @id_contact)
    AND (@id_contactForTheme IS NULL Or 
            (p.id_publication IN(SELECT id_publication FROM PubliSousTheme 
                WHERE id_soustheme IN(SELECT id_soustheme FROM ContactSousTheme WHERE id_contact = @id_contactForTheme)))
            Or (p.id_publication IN(SELECT id_publication FROM PubliTheme 
                WHERE id_theme IN(SELECT id_theme FROM ContactTheme WHERE id_contact = @id_contactForTheme)))
            )
    AND (@ID_ActuChronique is NULL or id_actuChronique = @ID_ActuChronique)
    AND (@id_newsletter IS NULL Or p.id_publication IN(SELECT id_publication FROM ListActuNewsletter WHERE id_newsletter = @id_newsletter))
    AND (@sMotClef IS NULL 
        or contains((p.sTexte, p.sTitre), @sMotClefForFullText)
        Or Personne.sNom LIKE '%' + @sMotClef + '%' COLLATE Latin1_General_CI_AI
        Or Personne.sPrenom LIKE '%' + @sMotClef + '%' COLLATE Latin1_General_CI_AI
        Or Societe.sNom LIKE '%' + @sMotClef + '%' COLLATE Latin1_General_CI_AI
        )
    AND (@dtPublication IS NULL Or p.dtPublication >= @dtPublication)
    AND (
        @bParlonsFinance IS NULL Or
        (@bParlonsFinance = 0 AND p.id_publication NOT IN(SELECT id_publication FROM PubliTheme 
                WHERE id_theme IN(SELECT id_theme FROM Theme WHERE bParlonsFinance = 1)))
        Or (@bParlonsFinance = 1 AND p.id_publication IN(SELECT id_publication FROM PubliTheme 
                WHERE id_theme IN(SELECT id_theme FROM Theme WHERE bParlonsFinance = 1))))
    AND (
        @bPartenaires IS NULL Or
        (@bPartenaires = 0 AND p.id_publication NOT IN(SELECT id_publication FROM PubliTheme 
                WHERE id_theme IN(SELECT id_theme FROM Theme WHERE 0 = 1)))
        Or (@bPartenaires = 1 AND p.id_publication IN(SELECT id_publication FROM PubliTheme 
                WHERE id_theme IN(SELECT id_theme FROM Theme WHERE 0 = 1))))
    AND (
        @bUne IS NULL
        Or p.bUne = @bUne)
    AND (@bEditoParlonsFinance IS NULL
        Or p.bEditoParlonsFinance = @bEditoParlonsFinance)
        AND (@bEditoQuestionFonds IS NULL
        Or p.bEditoQuestionFonds = @bEditoQuestionFonds)
    AND (@dtDebPublication IS NULL Or p.dtPublication >= @dtDebPublication)
    AND (@dtFinPublication IS NULL Or p.dtPublication <= @dtFinPublication)
    AND (@bOnlyActuWithDroitReponse = 0 Or (@bOnlyActuWithDroitReponse = 1 AND p.id_linkedDroitReponse IS NOT NULL))
    and (@bOnlyForHomePage = 0 or (@bOnlyForHomePage = 1 and ac.bHomePage = 1))
    ORDER BY coalesce(p.dtPublication, p.dtCreate) DESC, p.id_publication DESC
END

Answer 1

当您第一次编译存储过程时，它的执行计划会被缓存。

如果 sproc 具有其定义可以显着更改包含查询的执行计划的参数(例如索引扫描与搜索)，则存储过程的缓存计划可能不适用于所有参数定义。

避免这种情况的一种方法是包含 RECOMPILE条款与 CREATE PROCEDURE陈述。

例子:

CREATE PROCEDURE dbo.mySpro
@myParam
WITH RECOMPILE
AS
BEGIN
 -- INSERT WORKLOAD HERE
END
GO

通过这样做，每次调用该过程时都会生成一个新计划。如 recompile time < time lost by its using the wrong cached plan , 这个值得用 WITH RECOMPILE .在您的情况下，每次您注意到它执行缓慢时，它还会为您节省手动重新编译此过程所需的时间/计划。