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：
1 select distinct b.MaterialID as matl_def_id, c.Descript, case when right(b.MESOrderID, 12) < '001000000000' then right(b.MESOrderID, 9) 2 else right(b.MESOrderID, 12) end as pom_order_id, a.LotName, a.SourceLotName as ComLot, 3 e.DefID as ComMaterials, e.Descript as ComMatDes, d.VendorID, d.DateCode,d.SNNote, b.OnPlantID,a.SNCUST 4 from 5 ( 6 select m.lotname, m.sourcelotname, m.opetypeid, m.OperationDate,n.SNCUST from View1 m 7 left join co_sn_link_customer as n on n.SNMes=m.LotName 8 where 9 ( m.LotName in (select val from fn_String_To_Table(@sn,',',1)) or (@sn) = '') and 10 ( m.sourcelotname in (select val from fn_String_To_Table(@BatchID,',',1)) or (@BatchID) = '')11 and (n.SNCust like '%'+ @SN_ext + '%' or (@SN_ext)='')12 ) a13 left join 14 (15 select * from Table1 where SNType = 'IntSN'16 and SNRuleName = 'ProductSNRule'17 and OnPlantID=@OnPlant18 ) b on b.SN = a.LotName19 inner join MMdefinitions as c on c.DefID = b.MaterialID20 left join Table1 as d on d.SN = a.SourceLotName 21 inner join MMDefinitions as e on e.DefID = d.MaterialID22 where not exists (23 select distinct LotName, SourceLotName from ELCV_ASSEMBLE_OPS 24 where LotName = a.SourceLotName and SourceLotName = a.LotName25 ) 26 and (d.DateCode in (select val from fn_String_To_Table(@DCode,',',1)) or (@DCode) = '')27 and (d.SNNote like '%'+@SNNote+'%' or (@SNNote) = '')28 and ((case when right(b.MESOrderID, 12) < '001000000000' then right(b.MESOrderID, 9) 29 else right(b.MESOrderID, 12) end) in (select val from fn_String_To_Table(@order_id,',',1)) or (@order_id) = '')30 and (e.DefID in (select val from fn_String_To_Table(@comdef,',',1)) or (@comdef) = '')31 --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32 --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：
1 /** 2 * 某某跟踪报表 3 **/ 4 --exec spName1 '','','','','','','公司代号' 5 CREATE Procedure spName1 6 @MESOrderID nvarchar(320), --工单号,最多30个 7 @LotName nvarchar(700), --产品序列号,最多50个 8 @DateCode nvarchar(500), --供应商批次号,最多30个 9 @BatchID nvarchar(700), --组装件序列号/物料批号,最多50个 10 @comdef nvarchar(700), --组装件物料编码,最多30个 11 @SNCust nvarchar(1600), --外部序列号,最多50个 12 @OnPlant nvarchar(20) --平台 13 AS 14 BEGIN 15 SET NOCOUNT ON; 16 /** 17 * 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 18 **/ 19 CREATE TABLE #FinalLotName 20 ( 21 LotName NVARCHAR(50), --序列号 22 SourceLotName NVARCHAR(50), --来源序列号 23 SNCust NVARCHAR(128) --外部序列号 24 ) 25 --1.1 26 IF @LotName<>'' 27 BEGIN 28 SELECT Val INTO #WorkLot FROM fn_String_To_Table(@LotName,',',1) 29 SELECT LotPK,LotName INTO #WorkLotPK FROM MMLots WITH(NOLOCK) WHERE EXISTS(SELECT 1 FROM #WorkLot b WHERE b.Val=MMLots.LotID) 30 31 --求SourceLotPK只能在这里求 32 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 33 34 SELECT a.LotPK,a.SourceLotPK,b.LotName INTO #WorkSourcePK2 FROM #WorkSourcePK a JOIN #WorkLotPK b ON a.LotPK=b.LotPK 35 36 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 37 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 38 DELETE FROM #FinalLotName 39 INSERT INTO #FinalLotName SELECT LotName,SourceLotName,SNCust FROM #FinalLotNameX1 40 END 41 --1.2 42 IF @BatchID<>'' 43 BEGIN 44 SELECT Val INTO #WorkSourceLot FROM fn_String_To_Table(@BatchID,',',1) 45 IF EXISTS(SELECT 1 FROM #FinalLotName)--如果@LotName也不为空 46 BEGIN 47 SELECT a.LotName,a.SourceLotName,a.SNCust INTO #FinalLotNameX2 FROM #FinalLotName a WHERE EXISTS(SELECT 1 FROM #WorkSourceLot b WHERE a.SourceLotName=b.Val) 48 DELETE FROM #FinalLotName 49 INSERT INTO #FinalLotName SELECT LotName,SourceLotName,SNCust FROM #FinalLotNameX2 50 END 51 ELSE --@LotName条件为空 52 BEGIN 53 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) 54 SELECT a.LotPK,a.SourceLotPK into #21 FROM MMLotOperations a WITH(NOLOCK) WHERE EXISTS(SELECT 1 FROM #2 b WHERE b.SourceLotPK=a.SourceLotPK) 55 SELECT a.LotPK,a.SourceLotPK,b.SourceLotName INTO #22 FROM #21 a JOIN #2 b ON a.SourceLotPK=b.SourceLotPK 56 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 57 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 58 DELETE FROM #FinalLotName 59 INSERT INTO #FinalLotName SELECT LotName,SourceLotName,SNCust FROM #FinalLotNameX21 60 END 61 END 62 --1.3 63 IF @SNCust<>'' 64 BEGIN 65 SELECT Val INTO #WorkCustomSN FROM fn_String_To_Table(@SNCust,',',1) 66 IF EXISTS(SELECT 1 FROM #FinalLotName)--前面两个条件至少有一个有值 67 BEGIN 68 SELECT a.LotName,a.SourceLotName,a.SNCust INTO #FinalLotNameX3 FROM #FinalLotName a WHERE EXISTS(SELECT 1 FROM #WorkCustomSN b WHERE a.SNCust=b.Val) 69 DELETE FROM #FinalLotName 70 INSERT INTO #FinalLotName SELECT LotName,SourceLotName,SNCust FROM #FinalLotNameX3 71 END 72 ELSE 73 BEGIN 74 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) 75 -------------------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] 76 SELECT LotPK,LotName INTO #WorkLotPKX FROM MMLots WITH(NOLOCK) WHERE EXISTS(SELECT 1 FROM #WorkLotX b WHERE b.SNMes=MMLots.LotID) 77 78 --求SourceLotPK只能在这里求 79 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 80 81 SELECT a.LotPK,a.SourceLotPK,b.LotName INTO #WorkSourcePK2X FROM #WorkSourcePKX a JOIN #WorkLotPKX b ON a.LotPK=b.LotPK 82 83 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 84 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 85 DELETE FROM #FinalLotName 86 INSERT INTO #FinalLotName SELECT LotName,SourceLotName,SNCust FROM #FinalLotNameX31 87 ----------------------- 88 END 89 END 90 91 /** 92 * 2)定义全局的临时表，用于替换第一个全局临时表。 93 **/ 94 CREATE TABLE #FinalCO_SN 95 ( 96 SN NVARCHAR(50), 97 SourceSN NVARCHAR(50), 98 SNCust NVARCHAR(128), 99 matl_def_id NVARCHAR(50),--sn的物料ID100 ComMaterials NVARCHAR(50), --SourceSN的物料ID101 MESOrderID NVARCHAR(20),102 OnPlantID NVARCHAR(20),103 VendorID NVARCHAR(20),104 DateCode NVARCHAR(20) ,105 SNNote NVARCHAR(512)106 )107 --2.1108 IF @MESOrderID<>''109 BEGIN110 -------------------------------将MESOrderID做特殊处理-----------------------------------111 SELECT Val INTO #WorkMESOrderID FROM fn_String_To_Table(@MESOrderID,',',1)112 IF @OnPlant='Comba'113 BEGIN114 UPDATE #WorkMESOrderID SET Val='C000'+Val WHERE LEN(Val)=9115 END116 ELSE117 BEGIN118 UPDATE #WorkMESOrderID SET Val='W000'+Val WHERE LEN(Val)=9119 END120 SELECT SN,MaterialID,MESOrderID,OnPlantID INTO #WorkCO_SN1 FROM CO_SN_GENERATION a WITH(NOLOCK)121 WHERE SNType='IntSN' AND SNRuleName = 'ProductSNRule' AND OnPlantID=@OnPlant122 AND EXISTS(SELECT 1 FROM #WorkMESOrderID b WHERE a.MESOrderID=b.Val)123 ------------------------------------------------------------------------------------------124 --条件判断(逻辑分析)开始125 IF EXISTS(SELECT 1 FROM #FinalLotName)--如果前面判断的查询条件有值126 BEGIN127 --查出SourceLotName对应的查询字段128 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)129 130 INSERT INTO #FinalCO_SN131 SELECT a.LotName,a.SourceLotName,d.SNCust,b.MaterialID,c.ComMaterials,b.MESOrderID,b.OnPlantID,c.VendorID,c.DateCode,c.SNNote FROM #FinalLotName a 132 LEFT JOIN #WorkCO_SN1 b ON a.LotName=b.SN133 LEFT JOIN #SourceLotNameTable c ON a.SourceLotName=c.SourceLotName134 LEFT JOIN CO_SN_LINK_CUSTOMER d WITH(NOLOCK) ON a.LotName=d.SNMes135 END136 ELSE137 BEGIN138 --已知SN集合求解对应的SourceSN和SNCust集合------------------------------------------139 SELECT LotPK,LotName INTO #WorkLotPK410 FROM MMLots WITH(NOLOCK) WHERE EXISTS(SELECT 1 FROM #WorkCO_SN1 b WHERE b.SN=MMLots.LotID)140 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 NULL141 SELECT a.LotPK,a.SourceLotPK,b.LotName INTO #WorkSourcePK430 FROM #WorkSourcePK420 a JOIN #WorkLotPK410 b ON a.LotPK=b.LotPK142 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143 144 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.SNMes145 DELETE FROM #FinalLotName146 INSERT INTO #FinalLotName SELECT LotName,SourceLotName,SNCust FROM #FinalLotNameX440147 -------------------------------------------------------------------------------------148 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)149 150 INSERT INTO #FinalCO_SN151 SELECT a.LotName,a.SourceLotName,a.SNCust,b.MaterialID,c.ComMaterials,b.MESOrderID,b.OnPlantID,c.VendorID,c.DateCode,c.SNNote FROM #FinalLotName a 152 LEFT JOIN #WorkCO_SN1 b ON a.LotName=b.SN153 LEFT JOIN #SourceLotNameTable2 c ON a.SourceLotName=c.SourceLotName154 END 155 END156 --2.2157 IF @DateCode<>''158 BEGIN159 SELECT Val INTO #WorkDateCode FROM fn_String_To_Table(@DateCode,',',1)160 --此@DataCode条件求解出来的是SourceSN161 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)162 ----------------------------------------------------------------------------------------------------163 --条件判断(逻辑分析)开始164 IF EXISTS(SELECT 1 FROM #FinalCO_SN)--如果前面判断的查询条件有值165 BEGIN166 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)167 DELETE FROM #FinalCO_SN168 INSERT INTO #FinalCO_SN SELECT LotName,SourceLotName,SNCust,MaterialID,ComMaterials,MESOrderID,OnPlantID,VendorID,DateCode,SNNote FROM #TMP51169 END170 ELSE171 BEGIN172 IF EXISTS(SELECT 1 FROM #FinalLotName)173 BEGIN174 --查出SourceLotName对应的查询字段175 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)176 --查出SN对应的查询字段177 SELECT SN,MaterialID,MESOrderID,OnPlantID INTO #WorkSNT510 FROM CO_SN_GENERATION a WITH(NOLOCK)178 WHERE SNType='IntSN' AND SNRuleName = 'ProductSNRule' AND OnPlantID=@OnPlant179 AND EXISTS(SELECT 1 FROM #FinalLotName b WHERE a.SN=b.LotName)180 181 INSERT INTO #FinalCO_SN182 SELECT a.LotName,a.SourceLotName,d.SNCust,b.MaterialID,c.ComMaterials,b.MESOrderID,b.OnPlantID,c.VendorID,c.DateCode,c.SNNote FROM #FinalLotName a 183 LEFT JOIN #WorkSNT510 b ON a.LotName=b.SN184 LEFT JOIN #WorkSourceSNT1 c ON a.SourceLotName=c.SourceSN185 LEFT JOIN CO_SN_LINK_CUSTOMER d WITH(NOLOCK) ON a.LotName=d.SNMes186 187 END188 ELSE189 BEGIN190 --已知SourceSN集合求解对应的SN和SNCust集合------------------------------------------191 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)192 SELECT a.LotPK,a.SourceLotPK into #WorkLotX520 FROM MMLotOperations a WITH(NOLOCK) WHERE EXISTS(SELECT 1 FROM #WorkLotX510 b WHERE b.SourceLotPK=a.SourceLotPK)193 SELECT a.LotPK,a.SourceLotPK,b.SrouceLotName INTO #WorkLotX530 FROM #WorkLotX520 a JOIN #WorkLotX510 b ON a.SourceLotPK=b.SourceLotPK194 195 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196 197 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.SNMes198 DELETE FROM #FinalLotName199 INSERT INTO #FinalLotName SELECT LotName,SourceLotName,SNCust FROM #WorkLotX540200 -------------------------------------------------------------------------------------201 SELECT SN,MaterialID,MESOrderID,OnPlantID INTO #WorkLotX550 FROM CO_SN_GENERATION a WITH(NOLOCK)202 WHERE SNType='IntSN' AND SNRuleName = 'ProductSNRule' AND OnPlantID=@OnPlant203 AND EXISTS(SELECT 1 FROM #FinalLotName b WHERE a.SN=b.LotName)204 205 INSERT INTO #FinalCO_SN206 SELECT a.LotName,a.SourceLotName,a.SNCust,b.MaterialID,c.ComMaterials,b.MESOrderID,b.OnPlantID,c.VendorID,c.DateCode,c.SNNote FROM #FinalLotName a 207 LEFT JOIN #WorkLotX550 b ON a.LotName=b.SN208 LEFT JOIN #WorkSourceSNT1 c ON a.SourceLotName=c.SourceSN209 END210 END211 END212 --2.3213 IF @comdef<>''214 BEGIN215 SELECT Val INTO #WorkComdef FROM fn_String_To_Table(@comdef,',',1)216 --此@comdef条件求解出来的是SourceSN217 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)218 ----------------------------------------------------------------------------------------------------219 --条件判断(逻辑分析)开始220 IF EXISTS(SELECT 1 FROM #FinalCO_SN)--如果前面判断的查询条件有值221 BEGIN222 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)223 DELETE FROM #FinalCO_SN224 INSERT INTO #FinalCO_SN SELECT LotName,SourceLotName,SNCust,MaterialID,ComMaterials,MESOrderID,OnPlantID,VendorID,DateCode,SNNote FROM #TMP516225 END226 ELSE227 BEGIN228 IF EXISTS(SELECT 1 FROM #FinalLotName)229 BEGIN230 --查出SourceLotName对应的查询字段231 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)232 --查出SN对应的查询字段233 SELECT SN,MaterialID,MESOrderID,OnPlantID INTO #WorkSNT5106 FROM CO_SN_GENERATION a WITH(NOLOCK)234 WHERE SNType='IntSN' AND SNRuleName = 'ProductSNRule' AND OnPlantID=@OnPlant235 AND EXISTS(SELECT 1 FROM #FinalLotName b WHERE a.SN=b.LotName)236 237 INSERT INTO #FinalCO_SN238 SELECT a.LotName,a.SourceLotName,d.SNCust,b.MaterialID,c.ComMaterials,b.MESOrderID,b.OnPlantID,c.VendorID,c.DateCode,c.SNNote FROM #FinalLotName a 239 LEFT JOIN #WorkSNT5106 b ON a.LotName=b.SN240 LEFT JOIN #WorkSourceSNT16 c ON a.SourceLotName=c.SourceSN241 LEFT JOIN CO_SN_LINK_CUSTOMER d WITH(NOLOCK) ON a.LotName=d.SNMes242 243 END244 ELSE245 BEGIN246 --已知SourceSN集合求解对应的SN和SNCust集合------------------------------------------247 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)248 SELECT a.LotPK,a.SourceLotPK into #WorkLotX5206 FROM MMLotOperations a WITH(NOLOCK) WHERE EXISTS(SELECT 1 FROM #WorkLotX5106 b WHERE b.SourceLotPK=a.SourceLotPK)249 SELECT a.LotPK,a.SourceLotPK,b.SrouceLotName INTO #WorkLotX5306 FROM #WorkLotX5206 a JOIN #WorkLotX5106 b ON a.SourceLotPK=b.SourceLotPK250 251 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252 253 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.SNMes254 DELETE FROM #FinalLotName255 INSERT INTO #FinalLotName SELECT LotName,SourceLotName,SNCust FROM #WorkLotX5406256 -------------------------------------------------------------------------------------257 SELECT SN,MaterialID,MESOrderID,OnPlantID INTO #WorkLotX5506 FROM CO_SN_GENERATION a WITH(NOLOCK)258 WHERE SNType='IntSN' AND SNRuleName = 'ProductSNRule' AND OnPlantID=@OnPlant259 AND EXISTS(SELECT 1 FROM #FinalLotName b WHERE a.SN=b.LotName)260 261 INSERT INTO #FinalCO_SN262 SELECT a.LotName,a.SourceLotName,a.SNCust,b.MaterialID,c.ComMaterials,b.MESOrderID,b.OnPlantID,c.VendorID,c.DateCode,c.SNNote FROM #FinalLotName a 263 LEFT JOIN #WorkLotX5506 b ON a.LotName=b.SN264 LEFT JOIN #WorkSourceSNT16 c ON a.SourceLotName=c.SourceSN265 END266 END267 END268 269 /**270 * 3)条件判断结束271 **/272 IF EXISTS(SELECT 1 FROM #FinalLotName)273 BEGIN274 IF EXISTS(SELECT 1 FROM #FinalCO_SN)275 BEGIN--3.1276 SELECT a.matl_def_id,b.Descript,a.MESOrderID AS pom_order_id,a.SN AS LotName,a.SourceSN AS ComLot,277 a.ComMaterials,c.Descript AS ComMatDes,a.VendorID,a.DateCode,a.SNNote,278 OnPlantID,SNCust FROM #FinalCO_SN a279 JOIN MMDefinitions b WITH(NOLOCK) ON a.matl_def_id=b.DefID280 JOIN MMDefinitions c WITH(NOLOCK) ON a.ComMaterials=c.DefID281 WHERE NOT EXISTS(select distinct SN, SourceSN from #FinalCO_SN x 282 where x.SN = a.SourceSN and x.SourceSN = a.SN)283 END284 ELSE285 BEGIN--3.2286 --3.2.1求解SN的必查字段287 SELECT SN,MaterialID,MESOrderID,OnPlantID INTO #FinalSNX1 FROM CO_SN_GENERATION a WITH(NOLOCK)288 WHERE SNType='IntSN' AND SNRuleName = 'ProductSNRule' AND OnPlantID=@OnPlant289 AND EXISTS(SELECT 1 FROM #FinalLotName b WHERE a.SN=b.LotName)290 --3.2.2求解SourceSN的必查字段291 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)292 293 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.SNCust294 FROM #FinalLotName a295 LEFT JOIN #FinalSNX1 b ON a.LotName=b.SN296 LEFT JOIN #FinalSNX2 c ON a.SourceLotName=c.SourceLotName297 JOIN MMDefinitions x WITH(NOLOCK) ON b.MaterialID=x.DefID298 JOIN MMDefinitions y WITH(NOLOCK) ON c.ComMaterials=y.DefID299 WHERE NOT EXISTS(300 SELECT DISTINCT * FROM #FinalLotName z301 WHERE z.LotName=a.SourceLotName and z.SourceLotName=a.LotName302 )303 END304 END305 ELSE306 BEGIN307 IF EXISTS(SELECT 1 FROM #FinalCO_SN)308 BEGIN--3.3309 SELECT a.matl_def_id,b.Descript,a.MESOrderID AS pom_order_id,a.SN AS LotName,a.SourceSN AS ComLot,310 a.ComMaterials,c.Descript AS ComMatDes,a.VendorID,a.DateCode,a.SNNote,311 OnPlantID,SNCust FROM #FinalCO_SN a312 JOIN MMDefinitions b WITH(NOLOCK) ON a.matl_def_id=b.DefID313 JOIN MMDefinitions c WITH(NOLOCK) ON a.ComMaterials=c.DefID314 WHERE NOT EXISTS(select distinct SN, SourceSN from #FinalCO_SN x 315 where x.SN = a.SourceSN and x.SourceSN = a.SN)316 END317 ELSE318 BEGIN--3.4319 PRINT 'There is no queryable condition,please enter at less a query conditon.'320 END321 END322 323 END324 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。
希望本文对你有帮助。