实战:上亿数据如何秒查

jopen 5年前

原文出处: 杭伟的博客(@杭伟H)   欢迎分享原创到伯乐头条

最近在忙着优化集团公司的一个报表。优化完成后,报表查询速度有从半小时以上(甚至查不出)到秒查的质变。从修改SQL查询语句逻辑到决定创建存储过程实现,花了我3天多的时间,在此总结一下,希望对朋友们有帮助。

数据背景

首先项目是西门子中国在我司实施部署的MES项目,由于项目是在产线上运作(3 years+),数据累积很大。在项目的数据库中,大概上亿条数据的表有5个以上,千万级数据的表10个以上,百万级数据的表,很多…

(历史问题,当初实施无人监管,无人监控数据库这块的性能问题。ps:我刚入职不久…)

不多说,直接贴西门子中国的开发人员在我司开发的SSRS报表中的SQL语句:

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是一个嵌套两层的视图(出于保密性,实际名称可能不同),里面有一张上亿数据的表和几张千万级数据的表做左连接查询  --Table1是一个数据记录超过1500万的表

这个查询语句,实际上通过我的检测和调查,在B/S系统前端已无法查出结果,半小时,一小时 … 。因为我直接在SQL查询分析器查,半小时都没有结果。

(原因是里面对一张上亿级数据表和3张千万级数据表做全表扫描查询)

不由感慨,西门子中国的素质(或者说责任感)就这样?

下面说说我的分析和走的弯路(思维误区),希望对你也有警醒。

探索和误区

首先相关表的索引,没有建全的,把索引给建上。

索引这步完成后,发现情况还是一样,查询速度几乎没有改善。后来想起相关千万级数据以上的表,都还没有建立表分区。于是考虑建立表分区以及数据复制的方案。

这里有必要说明下:我司报表用的是一个专门的数据库服务器,数据从产线订阅而来。就是常说的“读写分离”。

如果直接在原表上建立表分区,你会发现执行表分区的事物会直接死锁。原因是:表分区操作本身会锁表,产线还在推数据过来,这样很容易“阻塞”,“死锁”。

我想好的方案是:建立一个新表(空表),在新表上建好表分区,然后复制数据过来。

正打算这么干。等等!我好像进入了一个严重的误区!

分析: 原SQL语句和业务需求,是对产线的数据做产品以及序列号的追溯,关键是查询条件里没有有规律的”条件”(如日期、编号),

贸然做了表分区,在这里几乎没有意义!反而会降低查询性能!

好险!还是一步一步来,先做SQL语句分析。

一. 对原SQL语句的分析

1. 查询语句的where条件,有大量@var in … or (@var =”) 的片段

2. where条件有like ‘%’+@var+’%’

3. where条件有 case … end 函数

4. 多次连接同一表查询,另外使用本身已嵌套的视图表,是不是必须,是否可替代?

5. SQL语句有*号,视图中也有*号出现

二. 优化设计

首先是用存储过程改写,好处是设计灵活。

核心思想是:用一个或多个查询条件(查询条件要求至少输入一个)得到临时表,每个查询条件如果查到集合,就更新这张临时表,最后汇总的时候,只需判断这个临时表是否有值。以此类推,可以建立多个临时表,将查询条件汇总。

这样做目前来看至少两点好处:

1.省去了对变量进行 =@var or (@var=”)的判断;

2.抛弃sql拼接,提高代码可读性。

再有就是在书写存储过程,这个过程中要注意:

1. 尽量想办法使用临时表扫描替代全表扫描;

2. 抛弃in和not in语句,使用exists和not exists替代;

3. 和客户确认,模糊查询是否有必要,如没有必要,去掉like语句;

4. 注意建立适当的,符合场景的索引;

5. 踩死 “*” 号;

6. 避免在where条件中对字段进行函数操作;

7. 对实时性要求不高的报表,允许脏读(with(nolock))。

三. 存储过程

如果想参考优化设计片段的详细内容,请参阅SQL代码:

/**   * 某某跟踪报表   **/  --exec spName1 '','','','','','','公司代号'  CREATE Procedure spName1     @MESOrderID nvarchar(320), --工单号,最多30个     @LotName nvarchar(700),    --产品序列号,最多50个     @DateCode nvarchar(500),   --供应商批次号,最多30个     @BatchID nvarchar(700),    --组装件序列号/物料批号,最多50个     @comdef nvarchar(700),     --组装件物料编码,最多30个     @SNCust nvarchar(1600),    --外部序列号,最多50个     @OnPlant nvarchar(20)      --平台  AS  BEGIN      SET NOCOUNT ON;        /**       * 1)定义全局的临时表,先根据六个查询条件的任意一个,得出临时表结果       **/      CREATE TABLE #FinalLotName      (          LotName NVARCHAR(50),       --序列号          SourceLotName NVARCHAR(50), --来源序列号          SNCust NVARCHAR(128)        --外部序列号      )      --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只能在这里求          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的里面加不加WHERE RowDeleted=0待确定          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也不为空          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条件为空          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的里面加不加WHERE RowDeleted=0待确定                  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)--前面两个条件至少有一个有值          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)              -------------------以下逻辑和变量1(@LotName)类似[先根据外部序列号求解序列号,再照搬第一个判断变量的方式]              SELECT LotPK,LotName INTO #WorkLotPKX FROM MMLots WITH(NOLOCK) WHERE EXISTS(SELECT 1 FROM #WorkLotX b WHERE b.SNMes=MMLots.LotID)                --求SourceLotPK只能在这里求              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的里面加不加WHERE RowDeleted=0待确定              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)定义全局的临时表,用于替换第一个全局临时表。       **/      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          -------------------------------将MESOrderID做特殊处理-----------------------------------          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)          ------------------------------------------------------------------------------------------          --条件判断(逻辑分析)开始          IF EXISTS(SELECT 1 FROM #FinalLotName)--如果前面判断的查询条件有值          BEGIN              --查出SourceLotName对应的查询字段              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集合求解对应的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的里面加不加WHERE RowDeleted=0待确定                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条件求解出来的是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)          ----------------------------------------------------------------------------------------------------          --条件判断(逻辑分析)开始          IF EXISTS(SELECT 1 FROM #FinalCO_SN)--如果前面判断的查询条件有值          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对应的查询字段              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对应的查询字段              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集合求解对应的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的里面加不加WHERE RowDeleted=0待确定                    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条件求解出来的是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)          ----------------------------------------------------------------------------------------------------          --条件判断(逻辑分析)开始          IF EXISTS(SELECT 1 FROM #FinalCO_SN)--如果前面判断的查询条件有值          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对应的查询字段              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对应的查询字段              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集合求解对应的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的里面加不加WHERE RowDeleted=0待确定                    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)条件判断结束       **/      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的必查字段              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的必查字段              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

虽然牺牲了代码的可读性,但创造了性能价值。本人水平有限,还请各位不吝赐教!

最后,将SSRS报表替换成此存储过程后,SQL查询分析器是秒查的。B/S前端用时1~2秒!

四. 总结

平常的你是否偶尔会因急于完成任务而书写一堆性能极低的SQL语句呢?写出可靠性能的SQL语句不难,难的是习惯。

本文的优化思想很简单,关键点是避免全表扫描 & 注重SQL语句写法 & 索引,另外,如果你查询的表有可能会在查询时段更新,而实际业务需求允许脏读,可加with(nolock)预防查询被更新事物阻塞。