1. 程式人生 > 實用技巧 >耗時3天,上億資料如何做到秒級查詢?

耗時3天,上億資料如何做到秒級查詢?

最近在忙著優化集團公司的一個報表。優化完成後,報表查詢速度由從半小時以上(甚至查不出)到秒查的質變。從修改 SQL 查詢語句邏輯到決定建立儲存過程實現,花了我 3 天多的時間,在此總結一下,希望對朋友們有幫助。

資料背景

首先專案是西門子中國在我司實施部署的 MES 專案,由於專案是在產線上運作(3 years+),資料累積很大。

在專案的資料庫中,大概上億條資料的表有 5 個以上,千萬級資料的表 10 個以上,百萬級資料的表,很多…

(歷史問題,當初實施無人監管,無人監控資料庫這塊的效能問題。PS:我剛入職不久…)

不多說,直接貼西門子中國的開發人員在我司開發的 SSRS 報表中的 SQL 語句:

select distinct b.MaterialID as matl_def_id, c.Descript, case when right(b.MESOrderID, 12) < '001000000000' then right(b.MESOrderID, 9)  
else right(b.MESOrderID, 12) end  as pom_order_id, a.LotName, a.SourceLotName as ComLot, 
e.DefID as ComMaterials, e.Descript as ComMatDes, d.VendorID, d.DateCode,d.SNNote, b.OnPlantID,a.SNCUST
from  
(
    select m.lotname, m.sourcelotname, m.opetypeid, m.OperationDate,n.SNCUST from View1 m
    left join co_sn_link_customer as n on n.SNMes=m.LotName
    where 
    ( m.LotName in (select val from fn_String_To_Table(@sn,',',1)) or (@sn) = '') and 
    ( m.sourcelotname in (select val from fn_String_To_Table(@BatchID,',',1)) or (@BatchID) = '')
    and (n.SNCust like '%'+ @SN_ext + '%' or (@SN_ext)='')
) a
left join 
(
    select * from Table1 where SNType = 'IntSN'
    and SNRuleName = 'ProductSNRule'
    and OnPlantID=@OnPlant
) b on b.SN = a.LotName
inner join MMdefinitions as c on c.DefID = b.MaterialID
left join  Table1 as d on d.SN = a.SourceLotName 
inner join MMDefinitions as e on e.DefID = d.MaterialID
where not exists (
 select distinct LotName, SourceLotName from ELCV_ASSEMBLE_OPS 
where LotName = a.SourceLotName and SourceLotName = a.LotName
) 
and (d.DateCode in (select val from fn_String_To_Table(@DCode,',',1)) or (@DCode) = '')
and (d.SNNote  like '%'+@SNNote+'%' or (@SNNote) = '')
and ((case when right(b.MESOrderID, 12) < '001000000000' then right(b.MESOrderID, 9)  
else right(b.MESOrderID, 12) end) in (select val from fn_String_To_Table(@order_id,',',1)) or (@order_id) = '')
and (e.DefID in (select val from fn_String_To_Table(@comdef,',',1)) or (@comdef) = '')
--View1是一個巢狀兩層的檢視(出於保密性,實際名稱可能不同),裡面有一張上億資料的表和幾張千萬級資料的表做左連線查詢
--Table1是一個數據記錄超過1500萬的表

這個查詢語句,實際上通過我的檢測和調查,在 B/S 系統前端已無法查出結果,半小時,一小時...

因為我直接在 SQL 查詢分析器查,半小時都沒有結果。(原因是裡面對一張上億級資料表和 3 張千萬級資料表做全表掃描查詢)

不由感慨,西門子中國的素質(或者說責任感)就這樣?下面說說我的分析和走的彎路(思維誤區),希望對你也有警醒。

探索和誤區

首先相關表的索引,沒有建全的,把索引給建上。

索引這步完成後,發現情況還是一樣,查詢速度幾乎沒有改善。後來想起相關千萬級資料以上的表,都還沒有建立表分割槽。於是考慮建立表分割槽以及資料複製的方案。

這裡有必要說明下:
我司報表用的是一個專門的資料庫伺服器,資料從產線訂閱而來。就是常說的“讀寫分離”。

如果直接在原表上建立表分割槽,你會發現執行表分割槽的事物會直接死鎖。原因是:表分割槽操作本身會鎖表,產線還在推資料過來,這樣很容易“阻塞”,“死鎖”。

我想好的方案是:建立一個新表(空表),在新表上建好表分割槽,然後複製資料過來。

正打算這麼幹。等等!我好像進入了一個嚴重的誤區!

分析:
原 SQL 語句和業務需求,是對產線的資料做產品以及序列號的追溯,關鍵是查詢條件裡沒有有規律的”條件”(如日期、編號),貿然做了表分割槽,在這裡幾乎沒有意義!反而會降低查詢效能!

好險!還是一步一步來,先做 SQL 語句分析。

對原 SQL 語句的分析

對原 SQL 語句的分析如下:

  • 查詢語句的 where 條件,有大量 @var in … or (@var =”) 的片段。
  • where 條件有 like ‘%’+@var+’%’。
  • where 條件有 case … end 函式。
  • 多次連線同一表查詢,另外使用本身已巢狀的視圖表,是不是必須,是否可替代?
  • SQL 語句有號,檢視中也有號出現。

優化設計

首先是用儲存過程改寫,好處是設計靈活。

核心思想是:用一個或多個查詢條件(查詢條件要求至少輸入一個)得到臨時表,每個查詢條件如果查到集合,就更新這張臨時表,最後彙總的時候,只需判斷這個臨時表是否有值。

以此類推,可以建立多個臨時表,將查詢條件彙總。

這樣做目前來看至少兩點好處:

  • 省去了對變數進行 =@var or (@var=”)的判斷。
  • 拋棄 SQL 拼接,提高程式碼可讀性。

再有就是在書寫儲存過程,這個過程中要注意:

  • 儘量想辦法使用臨時表掃描替代全表掃描。
  • 拋棄 in 和 not in 語句,使用 exists 和 not exists 替代。
  • 和客戶確認,模糊查詢是否有必要,如沒有必要,去掉 like 語句。
  • 注意建立適當的,符合場景的索引。
  • 踩死 “*” 號。
  • 避免在 where 條件中對欄位進行函式操作。
  • 對實時性要求不高的報表,允許髒讀(with(nolock))。

儲存過程

如果想參考優化設計片段的詳細內容,請參閱 SQL 程式碼:

/**
 * 某某跟蹤報表
 **/
--exec spName1 '','','','','','','公司代號'
CREATE Procedure spName1
   @MESOrderID nvarchar(320), --工單號,最多30個
   @LotName nvarchar(700),    --產品序列號,最多50個
   @DateCode nvarchar(500),   --供應商批次號,最多30個
   @BatchID nvarchar(700),    --組裝件序列號/物料批號,最多50個
   @comdef nvarchar(700),     --組裝件物料編碼,最多30個
   @SNCust nvarchar(1600),    --外部序列號,最多50個
   @OnPlant nvarchar(20)      --平臺
AS
BEGIN
    SET NOCOUNT ON;  
    /**
     * 1)定義全域性的臨時表,先根據六個查詢條件的任意一個,得出臨時表結果
     **/
    CREATE TABLE #FinalLotName
    (
        LotName NVARCHAR(50),       --序列號
        SourceLotName NVARCHAR(50), --來源序列號
        SNCust NVARCHAR(128)        --外部序列號
    )
    --1.1
    IF @LotName<>''
    BEGIN
        SELECT Val INTO #WorkLot FROM fn_String_To_Table(@LotName,',',1)
        SELECT LotPK,LotName INTO #WorkLotPK FROM MMLots WITH(NOLOCK) WHERE EXISTS(SELECT 1 FROM #WorkLot b WHERE b.Val=MMLots.LotID)

        --求SourceLotPK只能在這裡求
        SELECT a.LotPK,a.SourceLotPK into #WorkSourcePK FROM MMLotOperations a WITH(NOLOCK) WHERE EXISTS(SELECT 1 FROM #WorkLotPK b WHERE b.LotPK=a.LotPK) AND a.SourceLotPK IS NOT NULL

        SELECT a.LotPK,a.SourceLotPK,b.LotName INTO #WorkSourcePK2 FROM #WorkSourcePK a JOIN #WorkLotPK b ON a.LotPK=b.LotPK

        INSERT INTO #FinalLotName SELECT a.LotName,b.LotName AS SourceLotName,NULL FROM #WorkSourcePK2 a JOIN (SELECT LotPK,LotName FROM MMLots WITH(NOLOCK) ) b on a.SourceLotPK=b.LotPK --b的裡面加不加WHERE RowDeleted=0待確定
        SELECT a.LotName,a.SourceLotName,b.SNCust INTO #FinalLotNameX1 FROM #FinalLotName a LEFT JOIN CO_SN_LINK_CUSTOMER b WITH(NOLOCK) ON a.LotName=b.SNMes
        DELETE FROM #FinalLotName
        INSERT INTO #FinalLotName SELECT LotName,SourceLotName,SNCust FROM #FinalLotNameX1
    END
    --1.2
    IF @BatchID<>''
    BEGIN
        SELECT Val INTO #WorkSourceLot FROM fn_String_To_Table(@BatchID,',',1)
        IF EXISTS(SELECT 1 FROM #FinalLotName)--如果@LotName也不為空
        BEGIN
            SELECT a.LotName,a.SourceLotName,a.SNCust INTO #FinalLotNameX2 FROM #FinalLotName a WHERE EXISTS(SELECT 1 FROM #WorkSourceLot b WHERE a.SourceLotName=b.Val)
            DELETE FROM #FinalLotName
            INSERT INTO #FinalLotName SELECT LotName,SourceLotName,SNCust FROM #FinalLotNameX2
        END
        ELSE --@LotName條件為空
        BEGIN
            SELECT LotPK AS SourceLotPK,LotName AS SourceLotName INTO #2 FROM MMLots WITH(NOLOCK) WHERE EXISTS(SELECT 1 FROM #WorkSourceLot b WHERE b.Val=MMLots.LotID)
            SELECT a.LotPK,a.SourceLotPK into #21 FROM MMLotOperations a WITH(NOLOCK) WHERE EXISTS(SELECT 1 FROM #2 b WHERE b.SourceLotPK=a.SourceLotPK)
            SELECT a.LotPK,a.SourceLotPK,b.SourceLotName INTO #22 FROM #21 a JOIN #2 b ON a.SourceLotPK=b.SourceLotPK    
            INSERT INTO #FinalLotName SELECT b.LotName,a.SourceLotName,NULL FROM #22 a JOIN (SELECT LotPK,LotName FROM MMLots WITH(NOLOCK) ) b on a.LotPK=b.LotPK --b的裡面加不加WHERE RowDeleted=0待確定    
            SELECT a.LotName,a.SourceLotName,b.SNCust INTO #FinalLotNameX21 FROM #FinalLotName a LEFT JOIN CO_SN_LINK_CUSTOMER b WITH(NOLOCK) ON a.LotName=b.SNMes
            DELETE FROM #FinalLotName
            INSERT INTO #FinalLotName SELECT LotName,SourceLotName,SNCust FROM #FinalLotNameX21        
        END
    END
    --1.3
    IF @SNCust<>''
    BEGIN
        SELECT Val INTO #WorkCustomSN FROM fn_String_To_Table(@SNCust,',',1)
        IF EXISTS(SELECT 1 FROM #FinalLotName)--前面兩個條件至少有一個有值
        BEGIN
            SELECT a.LotName,a.SourceLotName,a.SNCust INTO #FinalLotNameX3 FROM #FinalLotName a WHERE EXISTS(SELECT 1 FROM #WorkCustomSN b WHERE a.SNCust=b.Val)
            DELETE FROM #FinalLotName 
            INSERT INTO #FinalLotName SELECT LotName,SourceLotName,SNCust FROM #FinalLotNameX3
        END
        ELSE
        BEGIN
            SELECT a.SNMes INTO #WorkLotX FROM CO_SN_LINK_CUSTOMER a WITH(NOLOCK) WHERE EXISTS(SELECT 1 FROM #WorkCustomSN b WHERE a.SNCust=b.Val)
            -------------------以下邏輯和變數1(@LotName)類似[先根據外部序列號求解序列號,再照搬第一個判斷變數的方式]
            SELECT LotPK,LotName INTO #WorkLotPKX FROM MMLots WITH(NOLOCK) WHERE EXISTS(SELECT 1 FROM #WorkLotX b WHERE b.SNMes=MMLots.LotID)

            --求SourceLotPK只能在這裡求
            SELECT a.LotPK,a.SourceLotPK into #WorkSourcePKX FROM MMLotOperations a WITH(NOLOCK) WHERE EXISTS(SELECT 1 FROM #WorkLotPKX b WHERE b.LotPK=a.LotPK) AND a.SourceLotPK IS NOT NULL

            SELECT a.LotPK,a.SourceLotPK,b.LotName INTO #WorkSourcePK2X FROM #WorkSourcePKX a JOIN #WorkLotPKX b ON a.LotPK=b.LotPK

            INSERT INTO #FinalLotName SELECT a.LotName,b.LotName AS SourceLotName,NULL FROM #WorkSourcePK2X a JOIN (SELECT LotPK,LotName FROM MMLots WITH(NOLOCK) ) b on a.SourceLotPK=b.LotPK --b的裡面加不加WHERE RowDeleted=0待確定
            SELECT a.LotName,a.SourceLotName,b.SNCust INTO #FinalLotNameX31 FROM #FinalLotName a LEFT JOIN CO_SN_LINK_CUSTOMER b WITH(NOLOCK) ON a.LotName=b.SNMes
            DELETE FROM #FinalLotName
            INSERT INTO #FinalLotName SELECT LotName,SourceLotName,SNCust FROM #FinalLotNameX31
            -----------------------
        END
    END

    /**
     * 2)定義全域性的臨時表,用於替換第一個全域性臨時表。
     **/
    CREATE TABLE #FinalCO_SN
    (
        SN NVARCHAR(50),
        SourceSN NVARCHAR(50),
        SNCust NVARCHAR(128),
        matl_def_id NVARCHAR(50),--sn的物料ID
        ComMaterials NVARCHAR(50),  --SourceSN的物料ID
        MESOrderID NVARCHAR(20),
        OnPlantID NVARCHAR(20),
        VendorID NVARCHAR(20),
        DateCode NVARCHAR(20) ,
        SNNote NVARCHAR(512)
    )
    --2.1
    IF @MESOrderID<>''
    BEGIN
        -------------------------------將MESOrderID做特殊處理-----------------------------------
        SELECT Val INTO #WorkMESOrderID FROM fn_String_To_Table(@MESOrderID,',',1)
        IF @OnPlant='Comba'
        BEGIN
            UPDATE #WorkMESOrderID SET Val='C000'+Val WHERE LEN(Val)=9
        END
        ELSE
        BEGIN
            UPDATE #WorkMESOrderID SET Val='W000'+Val WHERE LEN(Val)=9
        END
        SELECT SN,MaterialID,MESOrderID,OnPlantID INTO #WorkCO_SN1 FROM CO_SN_GENERATION a WITH(NOLOCK)
        WHERE SNType='IntSN' AND SNRuleName = 'ProductSNRule' AND OnPlantID=@OnPlant
        AND EXISTS(SELECT 1 FROM #WorkMESOrderID b WHERE a.MESOrderID=b.Val)
        ------------------------------------------------------------------------------------------
        --條件判斷(邏輯分析)開始
        IF EXISTS(SELECT 1 FROM #FinalLotName)--如果前面判斷的查詢條件有值
        BEGIN
            --查出SourceLotName對應的查詢欄位
            SELECT a.SN AS SourceLotName,a.VendorID,a.DateCode,a.SNNote,a.MaterialID AS ComMaterials INTO #SourceLotNameTable FROM CO_SN_GENERATION a WITH(NOLOCK) WHERE EXISTS(SELECT 1 FROM #FinalLotName b WHERE a.SN=b.SourceLotName)

            INSERT INTO #FinalCO_SN
            SELECT a.LotName,a.SourceLotName,d.SNCust,b.MaterialID,c.ComMaterials,b.MESOrderID,b.OnPlantID,c.VendorID,c.DateCode,c.SNNote FROM #FinalLotName a 
            LEFT JOIN #WorkCO_SN1 b ON a.LotName=b.SN
            LEFT JOIN #SourceLotNameTable c ON a.SourceLotName=c.SourceLotName
            LEFT JOIN CO_SN_LINK_CUSTOMER d WITH(NOLOCK) ON a.LotName=d.SNMes
        END
        ELSE
        BEGIN
            --已知SN集合求解對應的SourceSN和SNCust集合------------------------------------------
            SELECT LotPK,LotName INTO #WorkLotPK410 FROM MMLots WITH(NOLOCK) WHERE EXISTS(SELECT 1 FROM #WorkCO_SN1 b WHERE b.SN=MMLots.LotID)
            SELECT a.LotPK,a.SourceLotPK into #WorkSourcePK420 FROM MMLotOperations a WITH(NOLOCK) WHERE EXISTS(SELECT 1 FROM #WorkLotPK410 b WHERE b.LotPK=a.LotPK) AND a.SourceLotPK IS NOT NULL
            SELECT a.LotPK,a.SourceLotPK,b.LotName INTO #WorkSourcePK430 FROM #WorkSourcePK420 a JOIN #WorkLotPK410 b ON a.LotPK=b.LotPK
            INSERT INTO #FinalLotName SELECT a.LotName,b.LotName AS SourceLotName,NULL FROM #WorkSourcePK430 a JOIN (SELECT LotPK,LotName FROM MMLots WITH(NOLOCK) ) b on a.SourceLotPK=b.LotPK --b的裡面加不加WHERE RowDeleted=0待確定

            SELECT a.LotName,a.SourceLotName,b.SNCust INTO #FinalLotNameX440 FROM #FinalLotName a LEFT JOIN CO_SN_LINK_CUSTOMER b WITH(NOLOCK) ON a.LotName=b.SNMes
            DELETE FROM #FinalLotName
            INSERT INTO #FinalLotName SELECT LotName,SourceLotName,SNCust FROM #FinalLotNameX440
            -------------------------------------------------------------------------------------
            SELECT a.SN AS SourceLotName,a.VendorID,a.DateCode,a.SNNote,a.MaterialID AS ComMaterials INTO #SourceLotNameTable2 FROM CO_SN_GENERATION a WITH(NOLOCK) WHERE EXISTS(SELECT 1 FROM #FinalLotName b WHERE a.SN=b.SourceLotName)

            INSERT INTO #FinalCO_SN
            SELECT a.LotName,a.SourceLotName,a.SNCust,b.MaterialID,c.ComMaterials,b.MESOrderID,b.OnPlantID,c.VendorID,c.DateCode,c.SNNote FROM #FinalLotName a 
            LEFT JOIN #WorkCO_SN1 b ON a.LotName=b.SN
            LEFT JOIN #SourceLotNameTable2 c ON a.SourceLotName=c.SourceLotName
        END    
    END
    --2.2
    IF @DateCode<>''
    BEGIN
        SELECT Val INTO #WorkDateCode FROM fn_String_To_Table(@DateCode,',',1)
        --此@DataCode條件求解出來的是SourceSN
        SELECT SN AS SourceSN,MaterialID AS ComMaterials,VendorID,DateCode,SNNote INTO #WorkSourceSNT1 FROM CO_SN_GENERATION a WITH(NOLOCK) WHERE EXISTS(SELECT 1 FROM #WorkDateCode b WHERE a.DateCode=b.Val)
        ----------------------------------------------------------------------------------------------------
        --條件判斷(邏輯分析)開始
        IF EXISTS(SELECT 1 FROM #FinalCO_SN)--如果前面判斷的查詢條件有值
        BEGIN
            SELECT a.LotName,a.SourceLotName,a.SNCust,a.MaterialID,a.ComMaterials,a.MESOrderID,a.OnPlantID,a.VendorID,a.DateCode,a.SNNote INTO #TMP51 FROM #FinalCO_SN a WHERE EXISTS (SELECT 1 FROM #WorkDateCode b WHERE a.DateCode=b.Val)
            DELETE FROM #FinalCO_SN
            INSERT INTO #FinalCO_SN SELECT LotName,SourceLotName,SNCust,MaterialID,ComMaterials,MESOrderID,OnPlantID,VendorID,DateCode,SNNote FROM #TMP51
        END
        ELSE
        BEGIN
            IF EXISTS(SELECT 1 FROM #FinalLotName)
            BEGIN
            --查出SourceLotName對應的查詢欄位
            SELECT a.SourceSN,a.VendorID,a.DateCode,a.SNNote,a.ComMaterials INTO #SourceLTX5 FROM #WorkSourceSNT1 a WHERE EXISTS(SELECT 1 FROM #FinalLotName b WHERE a.SourceSN=b.SourceLotName)
            --查出SN對應的查詢欄位
            SELECT SN,MaterialID,MESOrderID,OnPlantID INTO #WorkSNT510 FROM CO_SN_GENERATION a WITH(NOLOCK)
            WHERE SNType='IntSN' AND SNRuleName = 'ProductSNRule' AND OnPlantID=@OnPlant
            AND EXISTS(SELECT 1 FROM #FinalLotName b WHERE a.SN=b.LotName)

            INSERT INTO #FinalCO_SN
            SELECT a.LotName,a.SourceLotName,d.SNCust,b.MaterialID,c.ComMaterials,b.MESOrderID,b.OnPlantID,c.VendorID,c.DateCode,c.SNNote FROM #FinalLotName a 
            LEFT JOIN #WorkSNT510 b ON a.LotName=b.SN
            LEFT JOIN #WorkSourceSNT1 c ON a.SourceLotName=c.SourceSN
            LEFT JOIN CO_SN_LINK_CUSTOMER d WITH(NOLOCK) ON a.LotName=d.SNMes

            END
            ELSE
            BEGIN
                --已知SourceSN集合求解對應的SN和SNCust集合------------------------------------------
                SELECT LotPK AS SourceLotPK,LotName AS SrouceLotName INTO #WorkLotX510 FROM MMLots WITH(NOLOCK) WHERE EXISTS(SELECT 1 FROM #WorkSourceSNT1 b WHERE b.SourceSN=MMLots.LotID)
                SELECT a.LotPK,a.SourceLotPK into #WorkLotX520 FROM MMLotOperations a WITH(NOLOCK) WHERE EXISTS(SELECT 1 FROM #WorkLotX510 b WHERE b.SourceLotPK=a.SourceLotPK)
                SELECT a.LotPK,a.SourceLotPK,b.SrouceLotName INTO #WorkLotX530 FROM #WorkLotX520 a JOIN #WorkLotX510 b ON a.SourceLotPK=b.SourceLotPK

                INSERT INTO #FinalLotName SELECT b.LotName,a.SrouceLotName,NULL FROM #WorkLotX530 a JOIN (SELECT LotPK,LotName FROM MMLots WITH(NOLOCK) ) b on a.LotPK=b.LotPK --b的裡面加不加WHERE RowDeleted=0待確定

                SELECT a.LotName,a.SourceLotName,b.SNCust INTO #WorkLotX540 FROM #FinalLotName a LEFT JOIN CO_SN_LINK_CUSTOMER b WITH(NOLOCK) ON a.LotName=b.SNMes
                DELETE FROM #FinalLotName
                INSERT INTO #FinalLotName SELECT LotName,SourceLotName,SNCust FROM #WorkLotX540
                -------------------------------------------------------------------------------------
                SELECT SN,MaterialID,MESOrderID,OnPlantID INTO #WorkLotX550 FROM CO_SN_GENERATION a WITH(NOLOCK)
                WHERE SNType='IntSN' AND SNRuleName = 'ProductSNRule' AND OnPlantID=@OnPlant
                AND EXISTS(SELECT 1 FROM #FinalLotName b WHERE a.SN=b.LotName)

                INSERT INTO #FinalCO_SN
                SELECT a.LotName,a.SourceLotName,a.SNCust,b.MaterialID,c.ComMaterials,b.MESOrderID,b.OnPlantID,c.VendorID,c.DateCode,c.SNNote FROM #FinalLotName a 
                LEFT JOIN #WorkLotX550 b ON a.LotName=b.SN
                LEFT JOIN #WorkSourceSNT1 c ON a.SourceLotName=c.SourceSN
            END
        END
    END
    --2.3
    IF @comdef<>''
    BEGIN
        SELECT Val INTO #WorkComdef FROM fn_String_To_Table(@comdef,',',1)
        --此@comdef條件求解出來的是SourceSN
        SELECT SN AS SourceSN,MaterialID AS ComMaterials,VendorID,DateCode,SNNote INTO #WorkSourceSNT16 FROM CO_SN_GENERATION a WITH(NOLOCK) WHERE EXISTS(SELECT 1 FROM #WorkComdef b WHERE a.MaterialID=b.Val)
        ----------------------------------------------------------------------------------------------------
        --條件判斷(邏輯分析)開始
        IF EXISTS(SELECT 1 FROM #FinalCO_SN)--如果前面判斷的查詢條件有值
        BEGIN
            SELECT a.LotName,a.SourceLotName,a.SNCust,a.MaterialID,a.ComMaterials,a.MESOrderID,a.OnPlantID,a.VendorID,a.DateCode,a.SNNote INTO #TMP516 FROM #FinalCO_SN a WHERE EXISTS (SELECT 1 FROM #WorkComdef b WHERE a.matl_def_id=b.Val)
            DELETE FROM #FinalCO_SN
            INSERT INTO #FinalCO_SN SELECT LotName,SourceLotName,SNCust,MaterialID,ComMaterials,MESOrderID,OnPlantID,VendorID,DateCode,SNNote FROM #TMP516
        END
        ELSE
        BEGIN
            IF EXISTS(SELECT 1 FROM #FinalLotName)
            BEGIN
            --查出SourceLotName對應的查詢欄位
            SELECT a.SourceSN,a.VendorID,a.DateCode,a.SNNote,a.ComMaterials INTO #SourceLTX56 FROM #WorkSourceSNT16 a WHERE EXISTS(SELECT 1 FROM #FinalLotName b WHERE a.SourceSN=b.SourceLotName)
            --查出SN對應的查詢欄位
            SELECT SN,MaterialID,MESOrderID,OnPlantID INTO #WorkSNT5106 FROM CO_SN_GENERATION a WITH(NOLOCK)
            WHERE SNType='IntSN' AND SNRuleName = 'ProductSNRule' AND OnPlantID=@OnPlant
            AND EXISTS(SELECT 1 FROM #FinalLotName b WHERE a.SN=b.LotName)

            INSERT INTO #FinalCO_SN
            SELECT a.LotName,a.SourceLotName,d.SNCust,b.MaterialID,c.ComMaterials,b.MESOrderID,b.OnPlantID,c.VendorID,c.DateCode,c.SNNote FROM #FinalLotName a 
            LEFT JOIN #WorkSNT5106 b ON a.LotName=b.SN
            LEFT JOIN #WorkSourceSNT16 c ON a.SourceLotName=c.SourceSN
            LEFT JOIN CO_SN_LINK_CUSTOMER d WITH(NOLOCK) ON a.LotName=d.SNMes

            END
            ELSE
            BEGIN
                --已知SourceSN集合求解對應的SN和SNCust集合------------------------------------------
                SELECT LotPK AS SourceLotPK,LotName AS SrouceLotName INTO #WorkLotX5106 FROM MMLots WITH(NOLOCK) WHERE EXISTS(SELECT 1 FROM #WorkSourceSNT16 b WHERE b.SourceSN=MMLots.LotID)
                SELECT a.LotPK,a.SourceLotPK into #WorkLotX5206 FROM MMLotOperations a WITH(NOLOCK) WHERE EXISTS(SELECT 1 FROM #WorkLotX5106 b WHERE b.SourceLotPK=a.SourceLotPK)
                SELECT a.LotPK,a.SourceLotPK,b.SrouceLotName INTO #WorkLotX5306 FROM #WorkLotX5206 a JOIN #WorkLotX5106 b ON a.SourceLotPK=b.SourceLotPK

                INSERT INTO #FinalLotName SELECT b.LotName,a.SrouceLotName,NULL FROM #WorkLotX5306 a JOIN (SELECT LotPK,LotName FROM MMLots WITH(NOLOCK) ) b on a.LotPK=b.LotPK --b的裡面加不加WHERE RowDeleted=0待確定

                SELECT a.LotName,a.SourceLotName,b.SNCust INTO #WorkLotX5406 FROM #FinalLotName a LEFT JOIN CO_SN_LINK_CUSTOMER b WITH(NOLOCK) ON a.LotName=b.SNMes
                DELETE FROM #FinalLotName
                INSERT INTO #FinalLotName SELECT LotName,SourceLotName,SNCust FROM #WorkLotX5406
                -------------------------------------------------------------------------------------
                SELECT SN,MaterialID,MESOrderID,OnPlantID INTO #WorkLotX5506 FROM CO_SN_GENERATION a WITH(NOLOCK)
                WHERE SNType='IntSN' AND SNRuleName = 'ProductSNRule' AND OnPlantID=@OnPlant
                AND EXISTS(SELECT 1 FROM #FinalLotName b WHERE a.SN=b.LotName)

                INSERT INTO #FinalCO_SN
                SELECT a.LotName,a.SourceLotName,a.SNCust,b.MaterialID,c.ComMaterials,b.MESOrderID,b.OnPlantID,c.VendorID,c.DateCode,c.SNNote FROM #FinalLotName a 
                LEFT JOIN #WorkLotX5506 b ON a.LotName=b.SN
                LEFT JOIN #WorkSourceSNT16 c ON a.SourceLotName=c.SourceSN
            END
        END
    END

    /**
     * 3)條件判斷結束
     **/
    IF EXISTS(SELECT 1 FROM #FinalLotName)
    BEGIN
        IF EXISTS(SELECT 1 FROM #FinalCO_SN)
        BEGIN--3.1
            SELECT a.matl_def_id,b.Descript,a.MESOrderID AS pom_order_id,a.SN AS LotName,a.SourceSN AS ComLot,
                   a.ComMaterials,c.Descript AS ComMatDes,a.VendorID,a.DateCode,a.SNNote,
                   OnPlantID,SNCust FROM #FinalCO_SN a
                   JOIN MMDefinitions b WITH(NOLOCK) ON a.matl_def_id=b.DefID
                   JOIN MMDefinitions c WITH(NOLOCK) ON a.ComMaterials=c.DefID
            WHERE NOT EXISTS(select distinct SN, SourceSN from #FinalCO_SN x 
                             where x.SN = a.SourceSN and x.SourceSN = a.SN)
        END
        ELSE
        BEGIN--3.2
            --3.2.1求解SN的必查欄位
            SELECT SN,MaterialID,MESOrderID,OnPlantID INTO #FinalSNX1 FROM CO_SN_GENERATION a WITH(NOLOCK)
            WHERE SNType='IntSN' AND SNRuleName = 'ProductSNRule' AND OnPlantID=@OnPlant
            AND EXISTS(SELECT 1 FROM #FinalLotName b WHERE a.SN=b.LotName)
            --3.2.2求解SourceSN的必查欄位
            SELECT a.SN AS SourceLotName,a.VendorID,a.DateCode,a.SNNote,a.MaterialID AS ComMaterials INTO #FinalSNX2 FROM CO_SN_GENERATION a WITH(NOLOCK) WHERE EXISTS(SELECT 1 FROM #FinalLotName b WHERE a.SN=b.SourceLotName)

            SELECT b.MaterialID AS matl_def_id,x.Descript,b.MESOrderID AS pom_order_id,b.SN AS LotName,c.SourceLotName AS ComLot,c.ComMaterials,y.Descript AS ComMatDes,c.VendorID,c.DateCode,c.SNNote,b.OnPlantID,a.SNCust
            FROM #FinalLotName a
            LEFT JOIN #FinalSNX1 b ON a.LotName=b.SN
            LEFT JOIN #FinalSNX2 c ON a.SourceLotName=c.SourceLotName
            JOIN MMDefinitions x WITH(NOLOCK) ON b.MaterialID=x.DefID
            JOIN MMDefinitions y WITH(NOLOCK) ON c.ComMaterials=y.DefID
            WHERE NOT EXISTS(
                SELECT DISTINCT * FROM #FinalLotName z
                WHERE z.LotName=a.SourceLotName and z.SourceLotName=a.LotName
            )
        END
    END
    ELSE
    BEGIN
        IF EXISTS(SELECT 1 FROM #FinalCO_SN)
        BEGIN--3.3
            SELECT a.matl_def_id,b.Descript,a.MESOrderID AS pom_order_id,a.SN AS LotName,a.SourceSN AS ComLot,
                   a.ComMaterials,c.Descript AS ComMatDes,a.VendorID,a.DateCode,a.SNNote,
                   OnPlantID,SNCust FROM #FinalCO_SN a
                   JOIN MMDefinitions b WITH(NOLOCK) ON a.matl_def_id=b.DefID
                   JOIN MMDefinitions c WITH(NOLOCK) ON a.ComMaterials=c.DefID
            WHERE NOT EXISTS(select distinct SN, SourceSN from #FinalCO_SN x 
                             where x.SN = a.SourceSN and x.SourceSN = a.SN)
        END
        ELSE
        BEGIN--3.4
            PRINT 'There is no queryable condition,please enter at less a query conditon.'
        END
    END

END
GO

雖然犧牲了程式碼的可讀性,但創造了效能價值。本人水平有限,還請各位不吝賜教!

最後,將 SSRS 報表替換成此儲存過程後,SQL 查詢分析器是秒查的。B/S 前端用時 1~2 秒!

總結

平常的你是否偶爾會因急於完成任務而書寫一堆效能極低的 SQL 語句呢?寫出可靠效能的 SQL 語句不難,難的是習慣。

本文的優化思想很簡單,關鍵點是避免全表掃描&注重 SQL 語句寫法&索引。

另外,如果你查詢的表有可能會在查詢時段更新,而實際業務需求允許髒讀,可加 with(nolock)預防查詢被更新事物阻塞。

來源:sohu.gg/jIp59N

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