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Case sensitivity

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89:: Users expect information retrieval systems to be able to have correct case sensitivity depending on the nature of an operation. Users looking for the word "dog" in an online journal probably do not wish to differentiate between "dog" or "Dog", as this is a writing distinction; the word should be matched whether it appears at the beginning of a sentence or not. On the other hand, users looking for information about a brand name, trademark, human name, or city name may be interested in performing a case-sensitive operation to filter out irrelevant results. For example, somebody searching for the name "Jade" would not want to find references to the mineral called "jade". On the English Knowledge for example a search for 31: 383:
are internally case-sensitive, and a readme.txt and a Readme.txt can coexist in the same directory. However, for practical purposes filenames behave as case-insensitive as far as users and most software are concerned. This can cause problems for developers or software coming from Unix-like
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A text search operation could be case-sensitive or case-insensitive, depending on the system, application, or context. The user can in many cases specify whether a search is sensitive to case, e.g. in most text editors, word processors, and Web browsers. A case-insensitive search is more
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comprehensive, finding "Language" (at the beginning of a sentence), "language", and "LANGUAGE" (in a title in capitals); a case-sensitive search will find the computer language "BASIC" but exclude most of the many unwanted instances of the word. For example, the
348:, because most file systems in other Unix-like environments are case-sensitive, and, for example, a source code tree for software for Unix-like systems might have both a file named Makefile and a file named makefile in the same directory. In addition, some Mac 284:, for example, variable names are case-sensitive but function names are not case-sensitive. This means that if a function is defined in lowercase, it can be called in uppercase, but if a variable is defined in lowercase, it cannot be referred to in uppercase. 103:: Authentication systems usually treat usernames as case-insensitive to make them easier to remember, reducing typing complexity, and eliminate the possibility of both mistakes and 74:, for example, or something with no ambiguity regarding capitalization and ambiguity between two or more terms cut down by capitalization, they may prefer a case-sensitive search. 344:
mode (so that a file created as readme.txt is shown as readme.txt and a file created as Readme.txt is shown as Readme.txt) by default. This causes some issues for developers and
70:, "dog" and "Dog" are of the same significance to them. Thus, they request a case-insensitive search. But when they search an online encyclopedia for information about the 367:
were case-insensitive and not case-preserving, so that a file whose name is entered as readme.txt or ReadMe.txt is saved as README.TXT. Later, with
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when two usernames are identical in every aspect except the case of one of their letters. However, these systems are not case-blind. They
117:: Authentication systems usually treat passwords as case-sensitive. This enables the users to increase the complexity of their passwords. 349: 328:
systems, filenames are usually case-sensitive (there can be separate readme.txt and Readme.txt files in the same directory).
141:: Some programming languages are case-sensitive for their variable names while others are not. For more details, see below. 508: 472: 646: 17: 524: 265: 201: 94: 253: 213: 277: 217: 400:
The link "Friendly Fire" must go through the (disambiguation) qualifier in a Knowledge article to avoid a
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in a case-insensitive (so that there cannot be a readme.txt and a Readme.txt in the same directory) but
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SQL most operations and searches are case-sensitive by default, while in most other
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engine is basically case-insensitive, with no option for case-sensitive search. In
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is case-insensitive and ignores underscores, as long as the first characters match.
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environments, similar to the problems with macOS case-insensitive file systems.
549:"case-sensitive-search - case sensitive google search - Google Project Hosting" 454: 376: 163:
sections of a URL may or may not be case-sensitive, depending on the receiving
71: 675: 298: 276:, in which the capitalisation of an identifier encodes information about its 90: 104: 375:
the FAT file systems became case-preserving as an extension of supporting
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so that users may choose an aesthetically pleasing username combination.
66:). For instance, when users interested in learning about dogs search an 30: 372: 164: 27:
Defines whether uppercase and lowercase letters are treated as distinct
414: 325: 280:. Some other programming languages have varying case sensitivity; in 233: 124: 39: 35: 352:
assume case insensitivity and fail on case-sensitive file systems.
333: 220:). Others are case-insensitive (i.e., not case-sensitive), such as 114: 100: 241: 205: 457:(February 1978). "Chapter 2: Types, Operators and Expressions". 356: 269: 67: 463:(1st ed.). Englewood Cliffs, NJ: Prentice Hall. p.  364: 360: 329: 229: 193: 413:
Although one can explicitly set a single database or column
622:"Case Sensitivity in Subsystem for UNIX-based Applications" 380: 368: 337: 257: 248:(for the syntax, and for some vendor implementations, e.g. 221: 127:
operating systems treat file names case-sensitively while
281: 245: 144: 42:"A" are the two case variants of the first letter in the 82:
Case sensitivity may differ depending on the situation:
97:(capitalized "Fire") returns the disambiguation page. 312:Case-insensitive operations are sometimes said to 332:is somewhat unusual in that, by default, it uses 309:'s SQL searches are case-insensitive by default. 673: 449: 131:is case-insensitive but, for most file systems, 109:preserve the case of the characters in the name 647:"Filenames are Case Sensitive on NTFS Volumes" 575:Oracle SQL Developer User's Guide, Release 1.5 597:"C.5.5.1 Case Sensitivity in String Searches" 179: 188:are case-sensitive for their identifiers ( 487: 572:"2.10 Making Queries Case Insensitive". 499:(1st ed.). O'Reilly Media. p.  443: 77: 29: 175:parts, however, are strictly lowercase. 14: 674: 379:. Later Windows file systems such as 264:. There are also languages, such as 24: 25: 693: 525:"Nim Manual: Identifier Equality" 319: 291: 93:returns the military article but 58:letters are treated as distinct ( 639: 614: 589: 565: 541: 517: 481: 431: 407: 394: 135:. For more details, see below. 13: 1: 424: 653:. 2006-11-01. Archived from 493:"Chapter 2: Language Basics" 7: 10: 698: 601:MySQL 5.0 Reference Manual 460:The C Programming Language 387: 180:In programming languages 56:uppercase and lowercase 47: 186:programming languages 78:Areas of significance 33: 417:to be case-sensitive 250:Microsoft SQL Server 232:(an exception being 489:Matsumoto, Yukihiro 451:Kernighan, Brian W. 252:, the data itself) 583:Oracle Corporation 529:nim-lang.github.io 497:Ruby in a nutshell 455:Ritchie, Dennis M. 324:In filesystems in 48: 651:Microsoft Support 129:Microsoft Windows 123:: Traditionally, 62:) or equivalent ( 16:(Redirected from 689: 666: 665: 663: 662: 643: 637: 636: 634: 633: 618: 612: 611: 609: 608: 593: 587: 586: 580: 569: 563: 562: 560: 559: 545: 539: 538: 536: 535: 521: 515: 514: 491:(January 2002). 485: 479: 478: 447: 441: 435: 418: 411: 405: 398: 64:case-insensitive 54:defines whether 52:case sensitivity 44:English alphabet 21: 18:Case-insensitive 697: 696: 692: 691: 690: 688: 687: 686: 672: 671: 670: 669: 660: 658: 657:on Jul 23, 2013 645: 644: 640: 631: 629: 626:Microsoft Learn 620: 619: 615: 606: 604: 595: 594: 590: 578: 571: 570: 566: 557: 555: 553:code.google.com 547: 546: 542: 533: 531: 523: 522: 518: 511: 486: 482: 475: 448: 444: 436: 432: 427: 422: 421: 412: 408: 399: 395: 390: 342:case-preserving 322: 294: 182: 133:case-preserving 80: 28: 23: 22: 15: 12: 11: 5: 695: 685: 684: 682:Capitalization 668: 667: 638: 613: 588: 585:. August 2013. 564: 540: 516: 509: 480: 473: 442: 429: 428: 426: 423: 420: 419: 406: 392: 391: 389: 386: 377:long filenames 321: 320:In filesystems 318: 293: 292:In text search 290: 181: 178: 177: 176: 142: 139:Variable names 136: 118: 112: 98: 79: 76: 72:United Nations 60:case-sensitive 50:In computers, 26: 9: 6: 4: 3: 2: 694: 683: 680: 679: 677: 656: 652: 648: 642: 627: 623: 617: 602: 598: 592: 584: 577: 576: 568: 554: 550: 544: 530: 526: 520: 512: 510:0-596-00214-9 506: 502: 498: 494: 490: 484: 476: 474:0-13-110163-3 470: 466: 462: 461: 456: 452: 446: 440: 434: 430: 416: 410: 403: 397: 393: 385: 382: 378: 374: 370: 366: 362: 358: 353: 351: 347: 343: 339: 335: 331: 327: 317: 315: 310: 308: 304: 300: 299:Google Search 289: 287: 283: 279: 275: 271: 267: 263: 259: 255: 251: 247: 243: 239: 235: 231: 227: 223: 219: 215: 211: 207: 203: 199: 195: 191: 187: 174: 170: 166: 162: 158: 154: 150: 146: 143: 140: 137: 134: 130: 126: 122: 119: 116: 113: 110: 106: 102: 99: 96: 95:Friendly Fire 92: 91:friendly fire 88: 85: 84: 83: 75: 73: 69: 65: 61: 57: 53: 45: 41: 37: 32: 19: 659:. Retrieved 655:the original 650: 641: 630:. Retrieved 628:. 2005-08-22 625: 616: 605:. Retrieved 600: 591: 574: 567: 556:. Retrieved 552: 543: 532:. Retrieved 528: 519: 496: 483: 458: 445: 433: 409: 396: 359:filesystems 354: 323: 313: 311: 295: 183: 172: 168: 160: 156: 152: 148: 81: 63: 59: 51: 49: 439:WP:DIFFCAPS 346:power users 238:Common Lisp 661:2013-05-20 632:2013-05-20 607:2013-05-20 558:2013-05-20 534:2019-04-27 425:References 373:Windows 95 355:The older 350:Installers 165:web server 121:File names 415:collation 402:WP:INTDAB 326:Unix-like 314:fold case 278:semantics 234:BBC BASIC 161:authority 125:Unix-like 115:Passwords 101:Usernames 87:Searching 40:uppercase 36:lowercase 676:Category 157:fragment 38:"a" and 603:. MySQL 266:Haskell 242:Fortran 228:, most 206:Verilog 507:  471:  404:error. 357:MS-DOS 303:Oracle 272:, and 270:Prolog 262:ooRexx 254:Pascal 230:BASICs 214:Python 169:scheme 167:. The 159:, and 147:: The 68:e-book 579:(PDF) 388:Notes 365:FAT16 361:FAT12 330:MacOS 218:Swift 184:Some 153:query 105:fraud 505:ISBN 469:ISBN 437:See 381:NTFS 369:VFAT 363:and 338:APFS 336:and 334:HFS+ 307:DBMS 260:and 258:Rexx 222:ABAP 216:and 210:Ruby 198:Java 173:host 171:and 149:path 145:URLs 34:The 371:in 286:Nim 282:PHP 246:SQL 236:), 226:Ada 194:C++ 678:: 649:. 624:. 599:. 581:. 551:. 527:. 503:. 495:. 467:. 465:33 453:; 274:Go 268:, 256:, 244:, 240:, 224:, 212:, 208:, 204:, 202:C# 200:, 196:, 192:, 155:, 151:, 664:. 635:. 610:. 561:. 537:. 513:. 501:9 477:. 190:C 46:. 20:)

Index

Case-insensitive

lowercase
uppercase
English alphabet
uppercase and lowercase
e-book
United Nations
Searching
friendly fire
Friendly Fire
Usernames
fraud
preserve the case of the characters in the name
Passwords
File names
Unix-like
Microsoft Windows
case-preserving
Variable names
URLs
web server
programming languages
C
C++
Java
C#
Verilog
Ruby
Python

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