LIKE vs SUBSTRING vs LEFT/RIGHT vs CHARINDEX
All too often developers need to query a database table for records which begin and/or end with a certain textual pattern. For instance, find all employees where their first name begins with “DAV”.
In my experience, there tends to be 4 common functions SQL developers rely upon for this.
That’s when this curious consultant decided to put them head-to-head: LIKE vs SUBSTRING vs LEFT / RIGHT vs CHARINDEX to see which is the fastest.
The Pre-Game Show
For testing purposes, the SQL code was executed on a Windows 2012 Server with 128GB memory, 16 core CPU rated at 2.54 Ghz, using Microsoft SQL Server 2014.
To make things a bit more interesting, the test is split into two parts:
- will test the speed of each against table table
- will test the speed of each against regular “string” data
The assumption here is there will be no race conditions or multi-threaded calls to this SQL code. This is just a straight up, head-to-head test.
To ensure SQL Server didn’t keep any queries (or anything for that matter) cached, the following code was run before each test:
|
1 2 3 4 5 6 7 8 9 10 |
checkpoint go DBCC DROPCLEANBUFFERS go DBCC FREESESSIONCACHE go DBCC FREEPROCCACHE go DBCC FREESYSTEMCACHE('ALL') go |
Two tables are created, and populated. The primary keys are the same. Three columns in each table will hold the exact same data, but:
- one will have a clustered index
- another will have a non-clustered index
- the third will have no index
just to see if they have any effect on performance.
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 |
--create temp table to hold all generated data IF OBJECT_ID('tempdb..#table1')IS NOT NULL DROP TABLE #table1 Create Table #table1 ( id int identity(1,1), aGuid uniqueidentifier not null, aClusteredIndexedColumn varchar(900) not null, aNonClusteredIndexedColumn varchar(900) not null, thecount int not null, aNonIndexedColumn varchar(900) not null ) --create temp table to hold test results IF OBJECT_ID('tempdb..#table2') IS NOT NULL DROP TABLE #table2 Create Table #table2 ( id int not null, matchedData varchar(900) not null ) --create the indexes print CAST(GETDATE() as varchar) + ' Started creating temptable indexes.' CREATE CLUSTERED INDEX IDX_cl ON #table1 (aClusteredIndexedColumn) CREATE NONCLUSTERED INDEX IDX_noncl ON #table1(aNonClusteredIndexedColumn) CREATE NONCLUSTERED INDEX IDX_id ON #table1(id) print CAST(GETDATE() as varchar) + ' Finished creating temptable indexes.' |
A query is done using each function to search for a particular string inserted within a UniqueIdentifier (guid). The results are inserted into the secondary table to make sure we have the same number of results for each test.
The complete source code can be found at the end of this article.
Are you a Betting Individual?
Here are the results, in milli-seconds, in our LIKE vs SUBSTRING vs LEFT/RIGHT vs CHARINDEX speed tests.
The winner is highlighted in green. There are no points for second place in this speed test.
|
Function |
Time to execute against Clustered Indexed column, in milliseconds, over 3 runs: |
|||
|
# Records: |
50,000 |
500,000 |
5,000,000 |
50,000,000 |
|
1: LIKE |
46, 43, 40 |
406, 413, 403 |
4016, 3986, 3996 |
39940, 39756, 40423 |
|
2: SUBSTRING |
46, 46, 46 |
440, 443, 443 |
2513, 2513, 2603 |
24760, 24873, 24270 |
|
40, 43, 43 |
406, 406, 410 |
2523, 2526, 2516 |
24713, 24770, 24823 |
|
|
4: CHARINDEX |
10, 10, 10 |
56, 56, 56 |
590, 593, 576 |
5713, 5683, 5730 |
|
Function |
Time to execute against Non-Clustered Indexed column, in milliseconds, over 3 runs: |
|||
|
# Records: |
50,000 |
500,000 |
5,000,000 |
50,000,000 |
|
1: LIKE |
43, 40, 40 |
70, 63, 73 |
680, 666, 670 |
7203, 6756, 6716 |
|
2: SUBSTRING |
103, 100, 103 |
256, 256, 260 |
2750, 2750, 2763 |
27076, 26940, 27053 |
|
100, 86, 100 |
253, 246, 250 |
2730, 2733, 2730 |
27166, 26633, 27123 |
|
|
4: CHARINDEX |
10, 10, 10 |
56, 53, 60 |
590, 590, 586 |
5810, 5763, 5690 |
|
Function |
Time to execute against Non-Indexed column, in milliseconds, over 3 runs: |
|||
|
# Records: |
50,000 |
500,000 |
5,000,000 |
50,000,000 |
|
1: LIKE |
43, 43, 40 |
63, 66, 70 |
670, 676, 663 |
6790, 7153, 6726 |
|
2: SUBSTRING |
126, 123, 123 |
396, 396, 396 |
3016, 2810, 2933 |
25463, 25643, 25420 |
|
46, 46, 43 |
246, 250, 253 |
2800, 2496, 2546 |
24690, 24750, 24810 |
|
|
4: CHARINDEX |
10, 6, 6 |
56, 56, 60 |
576, 590, 573 |
5790, 5836, 6276 |
|
Function |
Time to execute against varchar string, in milliseconds, over 3 runs: |
|||
|
# Records: |
50,000 |
500,000 |
5,000,000 |
50,000,000 |
|
1: LIKE |
126, 87, 75 |
909, 882, 822 |
8358, 8607, 8667 |
88610, 87349, 85341 |
|
2: SUBSTRING |
60, 45, 69 |
585, 582, 576 |
5571, 5673, 5670 |
57849, 54552, 56344 |
|
45, 45, 24 |
474, 396, 351 |
3945, 4044, 3990 |
39969, 39135, 40919 |
|
|
4: CHARINDEX |
60, 36, 66 |
618, 636, 564 |
5766, 5937, 5904 |
59773, 58412, 60198 |
Look Who Owned It!
CHARINDEX is clearly the undisputed king when it comes to querying a table column looking for a value. The 2 of the other 3 didn’t even come close in speed for me to acknowledge them as “competition”. I expected LIKE to do better, especially on index columns, but was quite surprised by CHARINDEX’s domination.
When it comes to searching a varchar/string variable, LEFT/RIGHT commanded the top spot.
In a nutshell, when you need to search for a substring at the beginning or end of data:
- when performing a query against a table column, use CHARINDEX
- when searching within a @varchar string variable, use LEFT/RIGHT
I’ve left you the SQL code below, so feel free to use it as a basis for conducting your own performance benchmarks.
Leave a comment below and share the knowledge if you have any suggestions or other ways of doing this!
The SQL Source Code
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 |
checkpoint go DBCC DROPCLEANBUFFERS go DBCC FREESESSIONCACHE go DBCC FREEPROCCACHE go DBCC FREESYSTEMCACHE('ALL') go DECLARE @MAX int = 500000 DECLARE @Counter int = 1 DECLARE @WhatToLookFor varchar(10) = '$%XX#abcde' DECLARE @tempString varchar(900) DECLARE @tempGUID UniqueIdentifier DECLARE @Start_Time datetime DECLARE @End_Time datetime --create temp table to hold all generated data IF OBJECT_ID('tempdb..#table1')IS NOT NULL DROP TABLE #table1 Create Table #table1 ( id int identity(1,1), aGuid uniqueidentifier not null, aClusteredIndexedColumn varchar(900) not null, aNonClusteredIndexedColumn varchar(900) not null, thecount int not null, aNonIndexedColumn varchar(900) not null ) --create temp table to hold test results IF OBJECT_ID('tempdb..#table2') IS NOT NULL DROP TABLE #table2 Create Table #table2 ( id int not null, matchedData varchar(900) not null ) --create temp table to hold resulting stats IF OBJECT_ID('tempdb..#stats') IS NOT NULL DROP TABLE #stats Create Table #stats ( id int identity(1,1), [task] varchar(900) not null, TotalRecordsCompared int null, MatchingRecords int null, StartTime datetime null, EndTime datetime null, TimeToRun varchar(50) not null ) print CAST(GETDATE() as varchar) + ' Started while loop creating temptable data.' SET NOCOUNT ON While @Counter <= @MAX BEGIN SET @tempGUID = NEWID() SET @tempString = CAST(@tempGuid as varchar(2000)) --To ensure some matches If (@Counter % 9 = 0) --Put at beginning SET @tempString = @WhatToLookFor + @tempString Else if (@Counter % 3 ) = 0 --put at end SET @tempString = @tempString + @WhatToLookFor --populate the temp table INSERT INTO #table1 VALUES ( @tempGuid ,@tempString ,@tempString ,@Counter ,@tempString ) SET @Counter = @Counter + 1 END SET NOCOUNT OFF print CAST(GETDATE() as varchar) + ' Finished creating temptable data.' --create the indexes print CAST(GETDATE() as varchar) + ' Started creating temptable indexes.' CREATE CLUSTERED INDEX IDX_cl ON #table1(aClusteredIndexedColumn) CREATE NONCLUSTERED INDEX IDX_noncl ON #table1(aNonClusteredIndexedColumn) CREATE NONCLUSTERED INDEX IDX_id ON #table1(id) print CAST(GETDATE() as varchar) + ' Finished creating temptable indexes.' --verify creation --select top 10 * from #table1 order by id --run the tests! --against clustered indexed column first ------------------------------------------- print 'Starting LIKE test against clustered indexed column' SET @START_TIME = GETDATE() INSERT INTO #table2 SELECT id, aClusteredIndexedColumn FROM #table1 WHERE aClusteredIndexedColumn like @WhatToLookFor + '%' or aClusteredIndexedColumn like '%' + @WhatToLookFor SET @END_TIME = GETDATE() print 'Finished' INSERT INTO #stats SELECT 'LIKE test against clustered indexed column' , @MAX , count(*) as [Matching Records] , @START_TIME as [Start Time] , @END_TIME as [End Time] , CAST(DATEDIFF(MILLISECOND, @START_TIME,@END_TIME) as varchar) + ' milliseconds' as [Time to Run] FROM #table2 Truncate Table #table2 print 'Starting SUBSTRING test against clustered indexed column' SET @START_TIME = GETDATE() INSERT INTO #table2 SELECT id , aClusteredIndexedColumn FROM #table1 WHERE SUBSTRING(aClusteredIndexedColumn,1, LEN(@WhatToLookFor)) = @WhatToLookFor or SUBSTRING(aClusteredIndexedColumn, LEN(aClusteredIndexedColumn) - LEN(@WhatToLookFor) + 1, LEN(@WhatToLookFor)) = @WhatToLookFor SET @END_TIME = GETDATE() print 'Finished' INSERT INTO #stats SELECT 'SUBSTRING test against clustered indexed column' , @MAX , count(*) as [Matching Records] , @START_TIME as [Start Time] , @END_TIME as [End Time] , CAST(DATEDIFF(MILLISECOND, @START_TIME,@END_TIME) as varchar) + ' milliseconds' as [Time to Run] FROM #table2 Truncate Table #table2 print 'Starting LEFT/RIGHT test against clustered indexed column' SET @START_TIME = GETDATE() INSERT INTO #table2 SELECT id, aClusteredIndexedColumn FROM #table1 WHERE LEFT(aClusteredIndexedColumn, LEN(@WhatToLookFor)) = @WhatToLookFor or RIGHT(aClusteredIndexedColumn, LEN(@WhatToLookFor)) = @WhatToLookFor SET @END_TIME = GETDATE() print 'Finished' INSERT INTO #stats SELECT 'LEFT/RIGHT test against clustered indexed column' , @MAX , count(*) as [Matching Records] , @START_TIME as [Start Time] , @END_TIME as [End Time] , CAST(DATEDIFF(MILLISECOND, @START_TIME,@END_TIME) as varchar) + ' milliseconds' as [Time to Run] FROM #table2 Truncate Table #table2 print 'Starting CHARINDEX test against clustered indexed column' SET @START_TIME = GETDATE() INSERT INTO #table2 SELECT id, aClusteredIndexedColumn FROM #table1 WHERE CHARINDEX(@WhatToLookFor,SUBSTRING(aClusteredIndexedColumn,1,LEN(@WhatToLookFor)),0) > 0 or CHARINDEX(@WhatToLookFor, SUBSTRING(aClusteredIndexedColumn, LEN(aClusteredIndexedColumn) - LEN(@WhatToLookFor) + 1, LEN(@WhatToLookFor)), 0) > 0 SET @END_TIME = GETDATE() print 'Finished' INSERT INTO #stats SELECT 'CHARINDEX test against clustered indexed column' , @MAX , count(*) as [Matching Records] , @START_TIME as [Start Time] , @END_TIME as [End Time] , CAST(DATEDIFF(MILLISECOND, @START_TIME,@END_TIME) as varchar) + ' milliseconds' as [Time to Run] FROM #table2 Truncate Table #table2 INSERT INTO #stats VALUES ('--------',null,null,null,null,'--------') --against nonclustered indexed column ---------------------------------------- print 'Starting LIKE test against nonclustered indexed column' SET @START_TIME = GETDATE() INSERT INTO #table2 SELECT id, aNonClusteredIndexedColumn FROM #table1 WHERE aNonClusteredIndexedColumn like @WhatToLookFor + '%' or aNonClusteredIndexedColumn like '%' + @WhatToLookFor SET @END_TIME = GETDATE() print 'Finished' INSERT INTO #stats SELECT 'LIKE test against Nonclustered indexed column' , @MAX , count(*) as [Matching Records] , @START_TIME as [Start Time] , @END_TIME as [End Time] , CAST(DATEDIFF(MILLISECOND , @START_TIME ,@END_TIME) as varchar) + ' milliseconds' as [Time to Run] FROM #table2 Truncate table #table2 print 'Starting SUBSTRING test against Nonclustered indexed column' SET @Start_Time = GETDATE() INSERT INTO #table2 SELECT id, aNonClusteredIndexedColumn FROM #table1 WHERE SUBSTRING(aNonClusteredIndexedColumn,1, LEN(@WhatToLookFor)) = @WhatToLookFor or SUBSTRING(aNonClusteredIndexedColumn, LEN(aNonClusteredIndexedColumn) - LEN(@WhatToLookFor) + 1, LEN(@WhatToLookFor)) = @WhatToLookFor SET @END_TIME = GETDATE() print 'Finished' INSERT INTO #stats SELECT 'SUBSTRING test against Nonclustered indexed column' , @MAX , count(*) as [Matching Records] , @START_TIME as [Start Time] , @END_TIME as [End Time] , CAST(DATEDIFF(MILLISECOND , @START_TIME ,@END_TIME) as varchar) + ' milliseconds' as [Time to Run] FROM #table2 Truncate table #table2 print 'Starting LEFT/RIGHT test against Nonclustered indexed column' SET @Start_Time = GETDATE() INSERT INTO #table2 SELECT id, aNonClusteredIndexedColumn FROM #table1 WHERE LEFT(aNonClusteredIndexedColumn, LEN(@WhatToLookFor)) = @WhatToLookFor or RIGHT(aNonClusteredIndexedColumn, LEN(@WhatToLookFor)) = @WhatToLookFor SET @END_TIME = GETDATE() print 'Finished' INSERT INTO #stats SELECT 'LEFT/RIGHT test against Nonclustered indexed column' , @MAX , count(*) as [Matching Records] , @START_TIME as [Start Time] , @END_TIME as [End Time] , CAST(DATEDIFF(MILLISECOND , @START_TIME ,@END_TIME) as varchar) + ' milliseconds' as [Time to Run] FROM #table2 Truncate table #table2 print 'Starting CHARINDEX test against nonclustered indexed column' SET @Start_Time = GETDATE() INSERT INTO #table2 SELECT id, aNonClusteredIndexedColumn FROM #table1 WHERE CHARINDEX(@WhatToLookFor,SUBSTRING(aNonClusteredIndexedColumn, 1, LEN(@WhatToLookFor)),0) > 0 or CHARINDEX(@WhatToLookFor, SUBSTRING(aNonClusteredIndexedColumn, LEN(aNonClusteredIndexedColumn) - LEN(@WhatToLookFor) + 1, LEN(@WhatToLookFor)),0) > 0 SET @END_TIME = GETDATE() print 'Finished' INSERT INTO #stats SELECT 'CHARINDEX test against Nonclustered indexed column' , @MAX , count(*) as [Matching Records] , @START_TIME as [Start Time] , @END_TIME as [End Time] , CAST(DATEDIFF(MILLISECOND , @START_TIME ,@END_TIME) as varchar) + ' milliseconds' as [Time to Run] FROM #table2 Truncate table #table2 INSERT INTO #stats VALUES ('--------',null,null,null,null,'--------') --Now against non indexed column -------------------------------------- print 'Starting LIKE test against NON-indexed column' SET @Start_Time = GETDATE() INSERT INTO #table2 SELECT id, aNonIndexedColumn FROM #table1 WHERE aNonIndexedColumn like @WhatToLookFor + '%' or aNonIndexedColumn like '%' + @WhatToLookFor SET @END_TIME = GETDATE() print 'Finished' INSERT INTO #stats SELECT 'LIKE test against NON-indexed column' , @MAX , count(*) as [Matching Records] , @START_TIME as [Start Time] , @END_TIME as [End Time] , CAST(DATEDIFF(MILLISECOND, @START_TIME,@END_TIME) as varchar) + ' milliseconds' as [Time to Run] FROM #table2 Truncate table #table2 print 'Starting SUBSTRING test against NON-indexed column' SET @Start_Time = GETDATE() INSERT INTO #table2 SELECT id, aNonIndexedColumn FROM #table1 WHERE SUBSTRING(aNonIndexedColumn, 1, LEN(@WhatToLookFor)) = @WhatToLookFor or SUBSTRING(aNonIndexedColumn, LEN(aNonIndexedColumn) - LEN(@WhatToLookFor) + 1, LEN(@WhatToLookFor)) = @WhatToLookFor SET @END_TIME = GETDATE() print 'Finished' INSERT INTO #stats SELECT 'SUBSTRING test against NON-indexed column' , @MAX , count(*) as [Matching Records] , @START_TIME as [Start Time] , @END_TIME as [End Time] , CAST(DATEDIFF(MILLISECOND, @START_TIME,@END_TIME) as varchar) + ' milliseconds' as [Time to Run] FROM #table2 Truncate table #table2 print 'Starting LEFT/RIGHT test against NON-indexed column' SET @Start_Time = GETDATE() INSERT INTO #table2 SELECT id, aNonIndexedColumn FROM #table1 WHERE LEFT(aNonIndexedColumn, LEN(@WhatToLookFor)) = @WhatToLookFor or RIGHT(aNonIndexedColumn,LEN(@WhatToLookFor)) = @WhatToLookFor SET @END_TIME = GETDATE() print 'Finished' INSERT INTO #stats SELECT 'LEFT/RIGHT test against NON-indexed column' ,@MAX ,count(*) as [Matching Records] , @START_TIME as [Start Time] , @END_TIME as [End Time] , CAST(DATEDIFF(MILLISECOND,@START_TIME,@END_TIME)as varchar) + ' milliseconds' as [Time to Run] FROM #table2 Truncate table #table2 print 'Starting CHARINDEX test against NON-indexed column' SET @Start_Time = GETDATE() INSERT INTO #table2 SELECT id, aNonIndexedColumn FROM #table1 WHERE CHARINDEX(@WhatToLookFor,SUBSTRING(aNonIndexedColumn,1, LEN(@WhatToLookFor)),0) > 0 or CHARINDEX(@WhatToLookFor, SUBSTRING(aNonIndexedColumn, LEN(aNonIndexedColumn) - LEN(@WhatToLookFor) + 1,LEN(@WhatToLookFor)),0) > 0 SET @END_TIME = GETDATE() print 'Finished' INSERT INTO #stats SELECT 'CHARINDEX test against NON-indexed column' , @MAX , count(*) as [Matching Records] , @START_TIME as [Start Time] , @END_TIME as [End Time] , CAST(DATEDIFF(MILLISECOND, @START_TIME,@END_TIME) as varchar) + ' milliseconds' as [Time to Run] FROM #table2 Truncate table #table2 INSERT INTO #stats VALUES ('--------',null,null,null,null,'--------') --Now do normal string comparisons ------------------------------------ SET NOCOUNT ON print 'Starting Looping string tests...' DECLARE @LikeTimeDiff int = 0 DECLARE @SubstringTimeDiff int = 0 DECLARE @LeftRightTimeDiff int = 0 DECLARE @CharindexTimeDiff int = 0 DECLARE @LikeMatches int = 0 DECLARE @SubstringMatches int = 0 DECLARE @LeftRightMatches int = 0 DECLARE @CharindexMatches int = 0 Set @Counter = 1 WHILE (@Counter <= @MAX) BEGIN Set @tempString =(Select aClusteredIndexedColumn FROM #table1 where id = @Counter) --Like SET @Start_Time = GETDATE() if (@tempString like @WhatToLookFor + '%' or @tempString like '%' + @WhatToLookFor) BEGIN SET @END_TIME = GETDATE() SET @LikeMatches = @LikeMatches + 1 END ELSE BEGIN SET @END_TIME = GETDATE() END SET @LikeTimeDiff = @LikeTimeDiff + DATEDIFF(MILLISECOND, @START_TIME,@END_TIME) --Substring SET @Start_Time = GETDATE() if (SUBSTRING(@tempString, 1, LEN(@WhatToLookFor)) = @WhatToLookFor or SUBSTRING(@tempString, LEN(@tempString) - LEN(@WhatToLookFor) + 1, LEN(@WhatToLookFor)) = @WhatToLookFor) BEGIN SET @END_TIME = GETDATE() SET @SubstringMatches = @SubstringMatches + 1 END ELSE BEGIN SET @END_TIME = GETDATE() END SET @SubstringTimeDiff = @SubstringTimeDiff + DATEDIFF(MILLISECOND, @START_TIME,@END_TIME) --Left/Right SET @Start_Time = GETDATE() if (LEFT(@tempString, LEN(@WhatToLookFor)) = @WhatToLookFor or RIGHT(@tempString, LEN(@WhatToLookFor)) = @WhatToLookFor) BEGIN SET @END_TIME = GETDATE() SET @LeftRightMatches = @LeftRightMatches + 1 END ELSE BEGIN SET @END_TIME = GETDATE() END SET @LeftRightTimeDiff = @LeftRightTimeDiff + DATEDIFF(MILLISECOND, @START_TIME,@END_TIME) --Charindex SET @Start_Time = GETDATE() if (CHARINDEX(@WhatToLookFor,SUBSTRING(@tempString, 1, LEN(@WhatToLookFor)),0) > 0 or CHARINDEX(@WhatToLookFor, SUBSTRING(@tempString, LEN(@tempString) - LEN(@WhatToLookFor) + 1, LEN(@WhatToLookFor)), 0) > 0) BEGIN SET @END_TIME = GETDATE() SET @CharindexMatches = @CharindexMatches + 1 END ELSE BEGIN SET @END_TIME = GETDATE() END SET @CharindexTimeDiff = @CharindexTimeDiff + DATEDIFF(MILLISECOND, @START_TIME,@END_TIME) SET @Counter = @Counter + 1 END print 'Finished looping string tests...' INSERT INTO #stats SELECT 'LIKE string test' , @MAX , @LikeMatches as [Matching Records] ,null ,null , CAST(@LikeTimeDiff as varchar) + ' milliseconds' as [Time to Run] INSERT INTO #stats SELECT 'SUBSTRING string test' , @MAX , @SubstringMatches as [Matching Records] ,null ,null ,CAST(@SubstringTimeDiff as varchar) + ' milliseconds' as [Time to Run] INSERT INTO #stats SELECT 'LEFT/RIGHT string test' , @MAX , @LeftRightMatches as [Matching Records] ,null ,null ,CAST(@LeftRightTimeDiff as varchar) + ' milliseconds' as [Time to Run] INSERT INTO #stats SELECT 'CHARINDEX string test' , @MAX , @CharindexMatches as [Matching Records] ,null ,null ,CAST(@CharindexTimeDiff as varchar) + ' milliseconds' as [Time to Run] SET NOCOUNT OFF --Display the results select * from #stats order by id --clean up IF OBJECT_ID('tempdb..#table1') IS NOT NULL DROP TABLE #table1 IF OBJECT_ID('tempdb..#table2') IS NOT NULL DROP TABLE #table2 IF OBJECT_ID('tempdb..#stats') IS NOT NULL DROP TABLE #stats |
