最近在忙着優化集團公司的一個報表。優化完成后，報表查詢速度有從半小時以上(甚至查不出)到秒查的質變。從修改SQL查詢語句邏輯到決定創建存儲
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。
數據背景
首先項目是西門子中國在我司實施部署的MES項目，由於項目是在產線上運作(3 years+)，數據累積很大。在項目的數據庫中，大概上億條數據的表有5個以上，千萬級數據的表10個以上，百萬級數據的表，很多...
(歷史問題，當初實施無人監管，無人監控數據庫這塊的性能問題。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：
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 ) a 13 left join 14 ( 15 select * from Table1 where SNType = 'IntSN' 16 and SNRuleName = 'ProductSNRule' 17 and OnPlantID=@OnPlant 18 ) b on b.SN = a.LotName 19 inner join MMdefinitions as c on c.DefID = b.MaterialID 20 left join Table1 as d on d.SN = a.SourceLotName 21 inner join MMDefinitions as e on e.DefID = d.MaterialID 22 where not exists ( 23 select distinct LotName, SourceLotName from ELCV_ASSEMBLE_OPS 24 where LotName = a.SourceLotName and SourceLotName = a.LotName 25 ) 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是一個嵌套兩層的視圖(出於保密性，實際名稱可能不同)，里面有一張上億數據的表和幾張千萬級數據的表做左連接查詢 32 --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。
(原因是里面對一張上億級數據表和3張千萬級數據表做全表掃描查詢)
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。
索引這步完成后，發現情況還是一樣，查詢速度幾乎沒有改善。后來想起相關千萬級數據以上的表，都還沒有建立表分區。於是考慮建立表分區以及數據復制的方案。
這里有必要說明下：我司報表用的是一個專門的數據庫服務器，數據從產線訂閱而來。就是常說的“讀寫分離”。
如果直接在原表上建立表分區，你會發現執行表分區的事物會直接死鎖。原因是：表分區操作本身會鎖表，產線還在推數據過來，這樣很容易“阻塞”，“死鎖”。
我想好的方案是：建立一個新表(空表)，在新表上建好表分區，然后復制數據過來。
正打算這么干。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，是對產線的數據做產品以及序列號的追溯，關鍵是查詢條件里沒有有規律的"條件"(如日期、編號)，
貿然做了表分區，在這里幾乎沒有意義！反而會降低查詢性能！
好險！還是一步一步來，先做SQL語句分析。
一. 對原SQL語句的分析
1. 查詢語句的where條件，有大量@var in ... or (@var ='') 的片段
2. where條件有like '%'+@var+'%'
3. where條件有 case ... end 函數
4. 多次連接同一表查詢，另外使用本身已嵌套的視圖表，是不是必須，是否可替代？
5. SQL語句有*號，視圖中也有*號出現
二. 優化設計
首先是用存儲過程改寫，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，最后匯總的時候，
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，將查詢條件匯總。
這樣做目前來看至少兩點好處：1.省去了對變量進行 =@var or (@var='')的判斷；
2.拋棄sql拼接，提高代碼可讀性。
再有就是在書寫存儲過程，這個過程中要注意：
1. 盡量想辦法使用臨時表掃描替代全表掃描；
2. 拋棄in和not in語句，使用exists和not exists替代；
3. 和客戶確認，模糊查詢是否有必要，如沒有必要，去掉like語句；
4. 注意建立適當的，符合場景的索引；
5. 踩死 "*" 號；
6. 避免在where條件中對字段進行函數操作；
7. 對實時性要求不高的報表，允許臟讀(with(nolock))。
三. 存儲過程
如果想參考優化設計片段的詳細內容，請參閱SQL代碼：
1 /** 2 * 某某跟蹤報表 3 **/ 4 --exec spName1 '','','','','','','公司代號' 5 CREATE Procedure spName1 6 @MESOrderID nvarchar(320), --工單號,最多30個 7 @LotName nvarchar(700), --產品序列號,最多50個 8 @DateCode nvarchar(500), --供應商批次號,最多30個 9 @BatchID nvarchar(700), --組裝件序列號/物料批號,最多50個 10 @comdef nvarchar(700), --組裝件物料編碼,最多30個 11 @SNCust nvarchar(1600), --外部序列號,最多50個 12 @OnPlant nvarchar(20) --平台 13 AS 14 BEGIN 15 SET NOCOUNT ON; 16 /** 17 * 1)定義全局的臨時表，先根據六個查詢條件的任意一個，得出臨時表結果 18 **/ 19 CREATE TABLE #FinalLotName 20 ( 21 LotName NVARCHAR(50), --序列號 22 SourceLotName NVARCHAR(50), --來源序列號 23 SNCust NVARCHAR(128) --外部序列號 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只能在這里求 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待確定 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也不為空 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條件為空 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待確定 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)--前面兩個條件至少有一個有值 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 -------------------以下邏輯和變量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只能在這里求 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待確定 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)定義全局的臨時表，用於替換第一個全局臨時表。 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ID 100 ComMaterials NVARCHAR(50), --SourceSN的物料ID 101 MESOrderID NVARCHAR(20), 102 OnPlantID NVARCHAR(20), 103 VendorID NVARCHAR(20), 104 DateCode NVARCHAR(20) , 105 SNNote NVARCHAR(512) 106 ) 107 --2.1 108 IF @MESOrderID<>'' 109 BEGIN 110 -------------------------------將MESOrderID做特殊處理----------------------------------- 111 SELECT Val INTO #WorkMESOrderID FROM fn_String_To_Table(@MESOrderID,',',1) 112 IF @OnPlant='Comba' 113 BEGIN 114 UPDATE #WorkMESOrderID SET Val='C000'+Val WHERE LEN(Val)=9 115 END 116 ELSE 117 BEGIN 118 UPDATE #WorkMESOrderID SET Val='W000'+Val WHERE LEN(Val)=9 119 END 120 SELECT SN,MaterialID,MESOrderID,OnPlantID INTO #WorkCO_SN1 FROM CO_SN_GENERATION a WITH(NOLOCK) 121 WHERE SNType='IntSN' AND SNRuleName = 'ProductSNRule' AND OnPlantID=@OnPlant 122 AND EXISTS(SELECT 1 FROM #WorkMESOrderID b WHERE a.MESOrderID=b.Val) 123 ------------------------------------------------------------------------------------------ 124 --條件判斷(邏輯分析)開始 125 IF EXISTS(SELECT 1 FROM #FinalLotName)--如果前面判斷的查詢條件有值 126 BEGIN 127 --查出SourceLotName對應的查詢字段 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_SN 131 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.SN 133 LEFT JOIN #SourceLotNameTable c ON a.SourceLotName=c.SourceLotName 134 LEFT JOIN CO_SN_LINK_CUSTOMER d WITH(NOLOCK) ON a.LotName=d.SNMes 135 END 136 ELSE 137 BEGIN 138 --已知SN集合求解對應的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 NULL 141 SELECT a.LotPK,a.SourceLotPK,b.LotName INTO #WorkSourcePK430 FROM #WorkSourcePK420 a JOIN #WorkLotPK410 b ON a.LotPK=b.LotPK 142 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待確定 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.SNMes 145 DELETE FROM #FinalLotName 146 INSERT INTO #FinalLotName SELECT LotName,SourceLotName,SNCust FROM #FinalLotNameX440 147 ------------------------------------------------------------------------------------- 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_SN 151 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.SN 153 LEFT JOIN #SourceLotNameTable2 c ON a.SourceLotName=c.SourceLotName 154 END 155 END 156 --2.2 157 IF @DateCode<>'' 158 BEGIN 159 SELECT Val INTO #WorkDateCode FROM fn_String_To_Table(@DateCode,',',1) 160 --此@DataCode條件求解出來的是SourceSN 161 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 --條件判斷(邏輯分析)開始 164 IF EXISTS(SELECT 1 FROM #FinalCO_SN)--如果前面判斷的查詢條件有值 165 BEGIN 166 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_SN 168 INSERT INTO #FinalCO_SN SELECT LotName,SourceLotName,SNCust,MaterialID,ComMaterials,MESOrderID,OnPlantID,VendorID,DateCode,SNNote FROM #TMP51 169 END 170 ELSE 171 BEGIN 172 IF EXISTS(SELECT 1 FROM #FinalLotName) 173 BEGIN 174 --查出SourceLotName對應的查詢字段 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對應的查詢字段 177 SELECT SN,MaterialID,MESOrderID,OnPlantID INTO #WorkSNT510 FROM CO_SN_GENERATION a WITH(NOLOCK) 178 WHERE SNType='IntSN' AND SNRuleName = 'ProductSNRule' AND OnPlantID=@OnPlant 179 AND EXISTS(SELECT 1 FROM #FinalLotName b WHERE a.SN=b.LotName) 180 181 INSERT INTO #FinalCO_SN 182 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.SN 184 LEFT JOIN #WorkSourceSNT1 c ON a.SourceLotName=c.SourceSN 185 LEFT JOIN CO_SN_LINK_CUSTOMER d WITH(NOLOCK) ON a.LotName=d.SNMes 186 187 END 188 ELSE 189 BEGIN 190 --已知SourceSN集合求解對應的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.SourceLotPK 194 195 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待確定 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.SNMes 198 DELETE FROM #FinalLotName 199 INSERT INTO #FinalLotName SELECT LotName,SourceLotName,SNCust FROM #WorkLotX540 200 ------------------------------------------------------------------------------------- 201 SELECT SN,MaterialID,MESOrderID,OnPlantID INTO #WorkLotX550 FROM CO_SN_GENERATION a WITH(NOLOCK) 202 WHERE SNType='IntSN' AND SNRuleName = 'ProductSNRule' AND OnPlantID=@OnPlant 203 AND EXISTS(SELECT 1 FROM #FinalLotName b WHERE a.SN=b.LotName) 204 205 INSERT INTO #FinalCO_SN 206 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.SN 208 LEFT JOIN #WorkSourceSNT1 c ON a.SourceLotName=c.SourceSN 209 END 210 END 211 END 212 --2.3 213 IF @comdef<>'' 214 BEGIN 215 SELECT Val INTO #WorkComdef FROM fn_String_To_Table(@comdef,',',1) 216 --此@comdef條件求解出來的是SourceSN 217 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 --條件判斷(邏輯分析)開始 220 IF EXISTS(SELECT 1 FROM #FinalCO_SN)--如果前面判斷的查詢條件有值 221 BEGIN 222 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_SN 224 INSERT INTO #FinalCO_SN SELECT LotName,SourceLotName,SNCust,MaterialID,ComMaterials,MESOrderID,OnPlantID,VendorID,DateCode,SNNote FROM #TMP516 225 END 226 ELSE 227 BEGIN 228 IF EXISTS(SELECT 1 FROM #FinalLotName) 229 BEGIN 230 --查出SourceLotName對應的查詢字段 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對應的查詢字段 233 SELECT SN,MaterialID,MESOrderID,OnPlantID INTO #WorkSNT5106 FROM CO_SN_GENERATION a WITH(NOLOCK) 234 WHERE SNType='IntSN' AND SNRuleName = 'ProductSNRule' AND OnPlantID=@OnPlant 235 AND EXISTS(SELECT 1 FROM #FinalLotName b WHERE a.SN=b.LotName) 236 237 INSERT INTO #FinalCO_SN 238 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.SN 240 LEFT JOIN #WorkSourceSNT16 c ON a.SourceLotName=c.SourceSN 241 LEFT JOIN CO_SN_LINK_CUSTOMER d WITH(NOLOCK) ON a.LotName=d.SNMes 242 243 END 244 ELSE 245 BEGIN 246 --已知SourceSN集合求解對應的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.SourceLotPK 250 251 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待確定 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.SNMes 254 DELETE FROM #FinalLotName 255 INSERT INTO #FinalLotName SELECT LotName,SourceLotName,SNCust FROM #WorkLotX5406 256 ------------------------------------------------------------------------------------- 257 SELECT SN,MaterialID,MESOrderID,OnPlantID INTO #WorkLotX5506 FROM CO_SN_GENERATION a WITH(NOLOCK) 258 WHERE SNType='IntSN' AND SNRuleName = 'ProductSNRule' AND OnPlantID=@OnPlant 259 AND EXISTS(SELECT 1 FROM #FinalLotName b WHERE a.SN=b.LotName) 260 261 INSERT INTO #FinalCO_SN 262 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.SN 264 LEFT JOIN #WorkSourceSNT16 c ON a.SourceLotName=c.SourceSN 265 END 266 END 267 END 268 269 /** 270 * 3)條件判斷結束 271 **/ 272 IF EXISTS(SELECT 1 FROM #FinalLotName) 273 BEGIN 274 IF EXISTS(SELECT 1 FROM #FinalCO_SN) 275 BEGIN--3.1 276 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 a 279 JOIN MMDefinitions b WITH(NOLOCK) ON a.matl_def_id=b.DefID 280 JOIN MMDefinitions c WITH(NOLOCK) ON a.ComMaterials=c.DefID 281 WHERE NOT EXISTS(select distinct SN, SourceSN from #FinalCO_SN x 282 where x.SN = a.SourceSN and x.SourceSN = a.SN) 283 END 284 ELSE 285 BEGIN--3.2 286 --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=@OnPlant 289 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.SNCust 294 FROM #FinalLotName a 295 LEFT JOIN #FinalSNX1 b ON a.LotName=b.SN 296 LEFT JOIN #FinalSNX2 c ON a.SourceLotName=c.SourceLotName 297 JOIN MMDefinitions x WITH(NOLOCK) ON b.MaterialID=x.DefID 298 JOIN MMDefinitions y WITH(NOLOCK) ON c.ComMaterials=y.DefID 299 WHERE NOT EXISTS( 300 SELECT DISTINCT * FROM #FinalLotName z 301 WHERE z.LotName=a.SourceLotName and z.SourceLotName=a.LotName 302 ) 303 END 304 END 305 ELSE 306 BEGIN 307 IF EXISTS(SELECT 1 FROM #FinalCO_SN) 308 BEGIN--3.3 309 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 a 312 JOIN MMDefinitions b WITH(NOLOCK) ON a.matl_def_id=b.DefID 313 JOIN MMDefinitions c WITH(NOLOCK) ON a.ComMaterials=c.DefID 314 WHERE NOT EXISTS(select distinct SN, SourceSN from #FinalCO_SN x 315 where x.SN = a.SourceSN and x.SourceSN = a.SN) 316 END 317 ELSE 318 BEGIN--3.4 319 PRINT 'There is no queryable condition,please enter at less a query conditon.' 320 END 321 END 322 323 END 324 GO
雖然犧牲了代碼的可讀性，但創造了性能價值。本人水平有限，還請各位不吝賜教！
最后，將SSRS報表替換成此存儲過程后，SQL查詢分析器是秒查的。B/S前端用時1~2秒！
四. 總結
平常的你是否偶爾會因急於完成任務而書寫一堆性能極低的SQL語句呢？寫出可靠性能的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臟讀，可加with(nolock)預防查詢被更新事物阻塞。
希望本文對你有幫助。